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1// SPDX-License-Identifier: GPL-2.02/*3 *  linux/fs/proc/base.c4 *5 *  Copyright (C) 1991, 1992 Linus Torvalds6 *7 *  proc base directory handling functions8 *9 *  1999, Al Viro. Rewritten. Now it covers the whole per-process part.10 *  Instead of using magical inumbers to determine the kind of object11 *  we allocate and fill in-core inodes upon lookup. They don't even12 *  go into icache. We cache the reference to task_struct upon lookup too.13 *  Eventually it should become a filesystem in its own. We don't use the14 *  rest of procfs anymore.15 *16 *17 *  Changelog:18 *  17-Jan-200519 *  Allan Bezerra20 *  Bruna Moreira <bruna.moreira@indt.org.br>21 *  Edjard Mota <edjard.mota@indt.org.br>22 *  Ilias Biris <ilias.biris@indt.org.br>23 *  Mauricio Lin <mauricio.lin@indt.org.br>24 *25 *  Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT26 *27 *  A new process specific entry (smaps) included in /proc. It shows the28 *  size of rss for each memory area. The maps entry lacks information29 *  about physical memory size (rss) for each mapped file, i.e.,30 *  rss information for executables and library files.31 *  This additional information is useful for any tools that need to know32 *  about physical memory consumption for a process specific library.33 *34 *  Changelog:35 *  21-Feb-200536 *  Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT37 *  Pud inclusion in the page table walking.38 *39 *  ChangeLog:40 *  10-Mar-200541 *  10LE Instituto Nokia de Tecnologia - INdT:42 *  A better way to walks through the page table as suggested by Hugh Dickins.43 *44 *  Simo Piiroinen <simo.piiroinen@nokia.com>:45 *  Smaps information related to shared, private, clean and dirty pages.46 *47 *  Paul Mundt <paul.mundt@nokia.com>:48 *  Overall revision about smaps.49 */50 51#include <linux/uaccess.h>52 53#include <linux/errno.h>54#include <linux/time.h>55#include <linux/proc_fs.h>56#include <linux/stat.h>57#include <linux/task_io_accounting_ops.h>58#include <linux/init.h>59#include <linux/capability.h>60#include <linux/file.h>61#include <linux/fdtable.h>62#include <linux/generic-radix-tree.h>63#include <linux/string.h>64#include <linux/seq_file.h>65#include <linux/namei.h>66#include <linux/mnt_namespace.h>67#include <linux/mm.h>68#include <linux/swap.h>69#include <linux/rcupdate.h>70#include <linux/kallsyms.h>71#include <linux/stacktrace.h>72#include <linux/resource.h>73#include <linux/module.h>74#include <linux/mount.h>75#include <linux/security.h>76#include <linux/ptrace.h>77#include <linux/printk.h>78#include <linux/cache.h>79#include <linux/cgroup.h>80#include <linux/cpuset.h>81#include <linux/audit.h>82#include <linux/poll.h>83#include <linux/nsproxy.h>84#include <linux/oom.h>85#include <linux/elf.h>86#include <linux/pid_namespace.h>87#include <linux/user_namespace.h>88#include <linux/fs_parser.h>89#include <linux/fs_struct.h>90#include <linux/slab.h>91#include <linux/sched/autogroup.h>92#include <linux/sched/mm.h>93#include <linux/sched/coredump.h>94#include <linux/sched/debug.h>95#include <linux/sched/stat.h>96#include <linux/posix-timers.h>97#include <linux/time_namespace.h>98#include <linux/resctrl.h>99#include <linux/cn_proc.h>100#include <linux/ksm.h>101#include <uapi/linux/lsm.h>102#include <trace/events/oom.h>103#include "internal.h"104#include "fd.h"105 106#include "../../lib/kstrtox.h"107 108/* NOTE:109 *	Implementing inode permission operations in /proc is almost110 *	certainly an error.  Permission checks need to happen during111 *	each system call not at open time.  The reason is that most of112 *	what we wish to check for permissions in /proc varies at runtime.113 *114 *	The classic example of a problem is opening file descriptors115 *	in /proc for a task before it execs a suid executable.116 */117 118static u8 nlink_tid __ro_after_init;119static u8 nlink_tgid __ro_after_init;120 121enum proc_mem_force {122	PROC_MEM_FORCE_ALWAYS,123	PROC_MEM_FORCE_PTRACE,124	PROC_MEM_FORCE_NEVER125};126 127static enum proc_mem_force proc_mem_force_override __ro_after_init =128	IS_ENABLED(CONFIG_PROC_MEM_NO_FORCE) ? PROC_MEM_FORCE_NEVER :129	IS_ENABLED(CONFIG_PROC_MEM_FORCE_PTRACE) ? PROC_MEM_FORCE_PTRACE :130	PROC_MEM_FORCE_ALWAYS;131 132static const struct constant_table proc_mem_force_table[] __initconst = {133	{ "always", PROC_MEM_FORCE_ALWAYS },134	{ "ptrace", PROC_MEM_FORCE_PTRACE },135	{ "never", PROC_MEM_FORCE_NEVER },136	{ }137};138 139static int __init early_proc_mem_force_override(char *buf)140{141	if (!buf)142		return -EINVAL;143 144	/*145	 * lookup_constant() defaults to proc_mem_force_override to preseve146	 * the initial Kconfig choice in case an invalid param gets passed.147	 */148	proc_mem_force_override = lookup_constant(proc_mem_force_table,149						  buf, proc_mem_force_override);150 151	return 0;152}153early_param("proc_mem.force_override", early_proc_mem_force_override);154 155struct pid_entry {156	const char *name;157	unsigned int len;158	umode_t mode;159	const struct inode_operations *iop;160	const struct file_operations *fop;161	union proc_op op;162};163 164#define NOD(NAME, MODE, IOP, FOP, OP) {			\165	.name = (NAME),					\166	.len  = sizeof(NAME) - 1,			\167	.mode = MODE,					\168	.iop  = IOP,					\169	.fop  = FOP,					\170	.op   = OP,					\171}172 173#define DIR(NAME, MODE, iops, fops)	\174	NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )175#define LNK(NAME, get_link)					\176	NOD(NAME, (S_IFLNK|S_IRWXUGO),				\177		&proc_pid_link_inode_operations, NULL,		\178		{ .proc_get_link = get_link } )179#define REG(NAME, MODE, fops)				\180	NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})181#define ONE(NAME, MODE, show)				\182	NOD(NAME, (S_IFREG|(MODE)),			\183		NULL, &proc_single_file_operations,	\184		{ .proc_show = show } )185#define ATTR(LSMID, NAME, MODE)				\186	NOD(NAME, (S_IFREG|(MODE)),			\187		NULL, &proc_pid_attr_operations,	\188		{ .lsmid = LSMID })189 190/*191 * Count the number of hardlinks for the pid_entry table, excluding the .192 * and .. links.193 */194static unsigned int __init pid_entry_nlink(const struct pid_entry *entries,195	unsigned int n)196{197	unsigned int i;198	unsigned int count;199 200	count = 2;201	for (i = 0; i < n; ++i) {202		if (S_ISDIR(entries[i].mode))203			++count;204	}205 206	return count;207}208 209static int get_task_root(struct task_struct *task, struct path *root)210{211	int result = -ENOENT;212 213	task_lock(task);214	if (task->fs) {215		get_fs_root(task->fs, root);216		result = 0;217	}218	task_unlock(task);219	return result;220}221 222static HWJS_SUSPENDS int proc_cwd_link(struct dentry *dentry, struct path *path)223{224	struct task_struct *task = get_proc_task(d_inode(dentry));225	int result = -ENOENT;226 227	if (task) {228		task_lock(task);229		if (task->fs) {230			get_fs_pwd(task->fs, path);231			result = 0;232		}233		task_unlock(task);234		put_task_struct(task);235	}236	return result;237}238 239static HWJS_SUSPENDS int proc_root_link(struct dentry *dentry, struct path *path)240{241	struct task_struct *task = get_proc_task(d_inode(dentry));242	int result = -ENOENT;243 244	if (task) {245		result = get_task_root(task, path);246		put_task_struct(task);247	}248	return result;249}250 251/*252 * If the user used setproctitle(), we just get the string from253 * user space at arg_start, and limit it to a maximum of one page.254 */255static ssize_t get_mm_proctitle(struct mm_struct *mm, char __user *buf,256				size_t count, unsigned long pos,257				unsigned long arg_start)258{259	char *page;260	int ret, got;261 262	if (pos >= PAGE_SIZE)263		return 0;264 265	page = (char *)__get_free_page(GFP_KERNEL);266	if (!page)267		return -ENOMEM;268 269	ret = 0;270	got = access_remote_vm(mm, arg_start, page, PAGE_SIZE, FOLL_ANON);271	if (got > 0) {272		int len = strnlen(page, got);273 274		/* Include the NUL character if it was found */275		if (len < got)276			len++;277 278		if (len > pos) {279			len -= pos;280			if (len > count)281				len = count;282			len -= copy_to_user(buf, page+pos, len);283			if (!len)284				len = -EFAULT;285			ret = len;286		}287	}288	free_page((unsigned long)page);289	return ret;290}291 292static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf,293			      size_t count, loff_t *ppos)294{295	unsigned long arg_start, arg_end, env_start, env_end;296	unsigned long pos, len;297	char *page, c;298 299	/* Check if process spawned far enough to have cmdline. */300	if (!mm->env_end)301		return 0;302 303	spin_lock(&mm->arg_lock);304	arg_start = mm->arg_start;305	arg_end = mm->arg_end;306	env_start = mm->env_start;307	env_end = mm->env_end;308	spin_unlock(&mm->arg_lock);309 310	if (arg_start >= arg_end)311		return 0;312 313	/*314	 * We allow setproctitle() to overwrite the argument315	 * strings, and overflow past the original end. But316	 * only when it overflows into the environment area.317	 */318	if (env_start != arg_end || env_end < env_start)319		env_start = env_end = arg_end;320	len = env_end - arg_start;321 322	/* We're not going to care if "*ppos" has high bits set */323	pos = *ppos;324	if (pos >= len)325		return 0;326	if (count > len - pos)327		count = len - pos;328	if (!count)329		return 0;330 331	/*332	 * Magical special case: if the argv[] end byte is not333	 * zero, the user has overwritten it with setproctitle(3).334	 *335	 * Possible future enhancement: do this only once when336	 * pos is 0, and set a flag in the 'struct file'.337	 */338	if (access_remote_vm(mm, arg_end-1, &c, 1, FOLL_ANON) == 1 && c)339		return get_mm_proctitle(mm, buf, count, pos, arg_start);340 341	/*342	 * For the non-setproctitle() case we limit things strictly343	 * to the [arg_start, arg_end[ range.344	 */345	pos += arg_start;346	if (pos < arg_start || pos >= arg_end)347		return 0;348	if (count > arg_end - pos)349		count = arg_end - pos;350 351	page = (char *)__get_free_page(GFP_KERNEL);352	if (!page)353		return -ENOMEM;354 355	len = 0;356	while (count) {357		int got;358		size_t size = min_t(size_t, PAGE_SIZE, count);359 360		got = access_remote_vm(mm, pos, page, size, FOLL_ANON);361		if (got <= 0)362			break;363		got -= copy_to_user(buf, page, got);364		if (unlikely(!got)) {365			if (!len)366				len = -EFAULT;367			break;368		}369		pos += got;370		buf += got;371		len += got;372		count -= got;373	}374 375	free_page((unsigned long)page);376	return len;377}378 379static ssize_t get_task_cmdline(struct task_struct *tsk, char __user *buf,380				size_t count, loff_t *pos)381{382	struct mm_struct *mm;383	ssize_t ret;384 385	mm = get_task_mm(tsk);386	if (!mm)387		return 0;388 389	ret = get_mm_cmdline(mm, buf, count, pos);390	mmput(mm);391	return ret;392}393 394static HWJS_SUSPENDS ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,395				     size_t count, loff_t *pos)396{397	struct task_struct *tsk;398	ssize_t ret;399 400	BUG_ON(*pos < 0);401 402	tsk = get_proc_task(file_inode(file));403	if (!tsk)404		return -ESRCH;405	ret = get_task_cmdline(tsk, buf, count, pos);406	put_task_struct(tsk);407	if (ret > 0)408		*pos += ret;409	return ret;410}411 412static const struct file_operations proc_pid_cmdline_ops = {413	.read	= proc_pid_cmdline_read,414	.llseek	= generic_file_llseek,415};416 417#ifdef CONFIG_KALLSYMS418/*419 * Provides a wchan file via kallsyms in a proper one-value-per-file format.420 * Returns the resolved symbol.  If that fails, simply return the address.421 */422static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,423			  struct pid *pid, struct task_struct *task)424{425	unsigned long wchan;426	char symname[KSYM_NAME_LEN];427 428	if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))429		goto print0;430 431	wchan = get_wchan(task);432	if (wchan && !lookup_symbol_name(wchan, symname)) {433		seq_puts(m, symname);434		return 0;435	}436 437print0:438	seq_putc(m, '0');439	return 0;440}441#endif /* CONFIG_KALLSYMS */442 443static int lock_trace(struct task_struct *task)444{445	int err = down_read_killable(&task->signal->exec_update_lock);446	if (err)447		return err;448	if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) {449		up_read(&task->signal->exec_update_lock);450		return -EPERM;451	}452	return 0;453}454 455static HWJS_SUSPENDS void unlock_trace(struct task_struct *task)456{457	up_read(&task->signal->exec_update_lock);458}459 460#ifdef CONFIG_STACKTRACE461 462#define MAX_STACK_TRACE_DEPTH	64463 464static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,465			  struct pid *pid, struct task_struct *task)466{467	unsigned long *entries;468	int err;469 470	/*471	 * The ability to racily run the kernel stack unwinder on a running task472	 * and then observe the unwinder output is scary; while it is useful for473	 * debugging kernel issues, it can also allow an attacker to leak kernel474	 * stack contents.475	 * Doing this in a manner that is at least safe from races would require476	 * some work to ensure that the remote task can not be scheduled; and477	 * even then, this would still expose the unwinder as local attack478	 * surface.479	 * Therefore, this interface is restricted to root.480	 */481	if (!file_ns_capable(m->file, &init_user_ns, CAP_SYS_ADMIN))482		return -EACCES;483 484	entries = kmalloc_array(MAX_STACK_TRACE_DEPTH, sizeof(*entries),485				GFP_KERNEL);486	if (!entries)487		return -ENOMEM;488 489	err = lock_trace(task);490	if (!err) {491		unsigned int i, nr_entries;492 493		nr_entries = stack_trace_save_tsk(task, entries,494						  MAX_STACK_TRACE_DEPTH, 0);495 496		for (i = 0; i < nr_entries; i++) {497			seq_printf(m, "[<0>] %pB\n", (void *)entries[i]);498		}499 500		unlock_trace(task);501	}502	kfree(entries);503 504	return err;505}506#endif507 508#ifdef CONFIG_SCHED_INFO509/*510 * Provides /proc/PID/schedstat511 */512static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns,513			      struct pid *pid, struct task_struct *task)514{515	if (unlikely(!sched_info_on()))516		seq_puts(m, "0 0 0\n");517	else518		seq_printf(m, "%llu %llu %lu\n",519		   (unsigned long long)task->se.sum_exec_runtime,520		   (unsigned long long)task->sched_info.run_delay,521		   task->sched_info.pcount);522 523	return 0;524}525#endif526 527#ifdef CONFIG_LATENCYTOP528static int lstats_show_proc(struct seq_file *m, void *v)529{530	int i;531	struct inode *inode = m->private;532	struct task_struct *task = get_proc_task(inode);533 534	if (!task)535		return -ESRCH;536	seq_puts(m, "Latency Top version : v0.1\n");537	for (i = 0; i < LT_SAVECOUNT; i++) {538		struct latency_record *lr = &task->latency_record[i];539		if (lr->backtrace[0]) {540			int q;541			seq_printf(m, "%i %li %li",542				   lr->count, lr->time, lr->max);543			for (q = 0; q < LT_BACKTRACEDEPTH; q++) {544				unsigned long bt = lr->backtrace[q];545 546				if (!bt)547					break;548				seq_printf(m, " %ps", (void *)bt);549			}550			seq_putc(m, '\n');551		}552 553	}554	put_task_struct(task);555	return 0;556}557 558static int lstats_open(struct inode *inode, struct file *file)559{560	return single_open(file, lstats_show_proc, inode);561}562 563static ssize_t lstats_write(struct file *file, const char __user *buf,564			    size_t count, loff_t *offs)565{566	struct task_struct *task = get_proc_task(file_inode(file));567 568	if (!task)569		return -ESRCH;570	clear_tsk_latency_tracing(task);571	put_task_struct(task);572 573	return count;574}575 576static const struct file_operations proc_lstats_operations = {577	.open		= lstats_open,578	.read		= seq_read,579	.write		= lstats_write,580	.llseek		= seq_lseek,581	.release	= single_release,582};583 584#endif585 586static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns,587			  struct pid *pid, struct task_struct *task)588{589	unsigned long totalpages = totalram_pages() + total_swap_pages;590	unsigned long points = 0;591	long badness;592 593	badness = oom_badness(task, totalpages);594	/*595	 * Special case OOM_SCORE_ADJ_MIN for all others scale the596	 * badness value into [0, 2000] range which we have been597	 * exporting for a long time so userspace might depend on it.598	 */599	if (badness != LONG_MIN)600		points = (1000 + badness * 1000 / (long)totalpages) * 2 / 3;601 602	seq_printf(m, "%lu\n", points);603 604	return 0;605}606 607struct limit_names {608	const char *name;609	const char *unit;610};611 612static const struct limit_names lnames[RLIM_NLIMITS] = {613	[RLIMIT_CPU] = {"Max cpu time", "seconds"},614	[RLIMIT_FSIZE] = {"Max file size", "bytes"},615	[RLIMIT_DATA] = {"Max data size", "bytes"},616	[RLIMIT_STACK] = {"Max stack size", "bytes"},617	[RLIMIT_CORE] = {"Max core file size", "bytes"},618	[RLIMIT_RSS] = {"Max resident set", "bytes"},619	[RLIMIT_NPROC] = {"Max processes", "processes"},620	[RLIMIT_NOFILE] = {"Max open files", "files"},621	[RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},622	[RLIMIT_AS] = {"Max address space", "bytes"},623	[RLIMIT_LOCKS] = {"Max file locks", "locks"},624	[RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},625	[RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},626	[RLIMIT_NICE] = {"Max nice priority", NULL},627	[RLIMIT_RTPRIO] = {"Max realtime priority", NULL},628	[RLIMIT_RTTIME] = {"Max realtime timeout", "us"},629};630 631/* Display limits for a process */632static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns,633			   struct pid *pid, struct task_struct *task)634{635	unsigned int i;636	unsigned long flags;637 638	struct rlimit rlim[RLIM_NLIMITS];639 640	if (!lock_task_sighand(task, &flags))641		return 0;642	memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);643	unlock_task_sighand(task, &flags);644 645	/*646	 * print the file header647	 */648	seq_puts(m, "Limit                     "649		"Soft Limit           "650		"Hard Limit           "651		"Units     \n");652 653	for (i = 0; i < RLIM_NLIMITS; i++) {654		if (rlim[i].rlim_cur == RLIM_INFINITY)655			seq_printf(m, "%-25s %-20s ",656				   lnames[i].name, "unlimited");657		else658			seq_printf(m, "%-25s %-20lu ",659				   lnames[i].name, rlim[i].rlim_cur);660 661		if (rlim[i].rlim_max == RLIM_INFINITY)662			seq_printf(m, "%-20s ", "unlimited");663		else664			seq_printf(m, "%-20lu ", rlim[i].rlim_max);665 666		if (lnames[i].unit)667			seq_printf(m, "%-10s\n", lnames[i].unit);668		else669			seq_putc(m, '\n');670	}671 672	return 0;673}674 675#ifdef CONFIG_HAVE_ARCH_TRACEHOOK676static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns,677			    struct pid *pid, struct task_struct *task)678{679	struct syscall_info info;680	u64 *args = &info.data.args[0];681	int res;682 683	res = lock_trace(task);684	if (res)685		return res;686 687	if (task_current_syscall(task, &info))688		seq_puts(m, "running\n");689	else if (info.data.nr < 0)690		seq_printf(m, "%d 0x%llx 0x%llx\n",691			   info.data.nr, info.sp, info.data.instruction_pointer);692	else693		seq_printf(m,694		       "%d 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx\n",695		       info.data.nr,696		       args[0], args[1], args[2], args[3], args[4], args[5],697		       info.sp, info.data.instruction_pointer);698	unlock_trace(task);699 700	return 0;701}702#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */703 704/************************************************************************/705/*                       Here the fs part begins                        */706/************************************************************************/707 708/* permission checks */709static bool proc_fd_access_allowed(struct inode *inode)710{711	struct task_struct *task;712	bool allowed = false;713	/* Allow access to a task's file descriptors if it is us or we714	 * may use ptrace attach to the process and find out that715	 * information.716	 */717	task = get_proc_task(inode);718	if (task) {719		allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);720		put_task_struct(task);721	}722	return allowed;723}724 725int proc_setattr(struct mnt_idmap *idmap, struct dentry *dentry,726		 struct iattr *attr)727{728	int error;729	struct inode *inode = d_inode(dentry);730 731	if (attr->ia_valid & ATTR_MODE)732		return -EPERM;733 734	error = setattr_prepare(&nop_mnt_idmap, dentry, attr);735	if (error)736		return error;737 738	setattr_copy(&nop_mnt_idmap, inode, attr);739	return 0;740}741 742/*743 * May current process learn task's sched/cmdline info (for hide_pid_min=1)744 * or euid/egid (for hide_pid_min=2)?745 */746static bool has_pid_permissions(struct proc_fs_info *fs_info,747				 struct task_struct *task,748				 enum proc_hidepid hide_pid_min)749{750	/*751	 * If 'hidpid' mount option is set force a ptrace check,752	 * we indicate that we are using a filesystem syscall753	 * by passing PTRACE_MODE_READ_FSCREDS754	 */755	if (fs_info->hide_pid == HIDEPID_NOT_PTRACEABLE)756		return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);757 758	if (fs_info->hide_pid < hide_pid_min)759		return true;760	if (in_group_p(fs_info->pid_gid))761		return true;762	return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);763}764 765 766static HWJS_SUSPENDS int proc_pid_permission(struct mnt_idmap *idmap,767			       struct inode *inode, int mask)768{769	struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb);770	struct task_struct *task;771	bool has_perms;772 773	task = get_proc_task(inode);774	if (!task)775		return -ESRCH;776	has_perms = has_pid_permissions(fs_info, task, HIDEPID_NO_ACCESS);777	put_task_struct(task);778 779	if (!has_perms) {780		if (fs_info->hide_pid == HIDEPID_INVISIBLE) {781			/*782			 * Let's make getdents(), stat(), and open()783			 * consistent with each other.  If a process784			 * may not stat() a file, it shouldn't be seen785			 * in procfs at all.786			 */787			return -ENOENT;788		}789 790		return -EPERM;791	}792	return generic_permission(&nop_mnt_idmap, inode, mask);793}794 795 796 797static const struct inode_operations proc_def_inode_operations = {798	.setattr	= proc_setattr,799};800 801static HWJS_SUSPENDS int proc_single_show(struct seq_file *m, void *v)802{803	struct inode *inode = m->private;804	struct pid_namespace *ns = proc_pid_ns(inode->i_sb);805	struct pid *pid = proc_pid(inode);806	struct task_struct *task;807	int ret;808 809	task = get_pid_task(pid, PIDTYPE_PID);810	if (!task)811		return -ESRCH;812 813	ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);814 815	put_task_struct(task);816	return ret;817}818 819static int proc_single_open(struct inode *inode, struct file *filp)820{821	return single_open(filp, proc_single_show, inode);822}823 824static const struct file_operations proc_single_file_operations = {825	.open		= proc_single_open,826	.read		= seq_read,827	.llseek		= seq_lseek,828	.release	= single_release,829};830 831 832struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode)833{834	struct task_struct *task = get_proc_task(inode);835	struct mm_struct *mm = ERR_PTR(-ESRCH);836 837	if (task) {838		mm = mm_access(task, mode | PTRACE_MODE_FSCREDS);839		put_task_struct(task);840 841		if (!IS_ERR_OR_NULL(mm)) {842			/* ensure this mm_struct can't be freed */843			mmgrab(mm);844			/* but do not pin its memory */845			mmput(mm);846		}847	}848 849	return mm;850}851 852static HWJS_SUSPENDS int __mem_open(struct inode *inode, struct file *file, unsigned int mode)853{854	struct mm_struct *mm = proc_mem_open(inode, mode);855 856	if (IS_ERR(mm))857		return PTR_ERR(mm);858 859	file->private_data = mm;860	return 0;861}862 863static HWJS_SUSPENDS int mem_open(struct inode *inode, struct file *file)864{865	if (WARN_ON_ONCE(!(file->f_op->fop_flags & FOP_UNSIGNED_OFFSET)))866		return -EINVAL;867	return __mem_open(inode, file, PTRACE_MODE_ATTACH);868}869 870static HWJS_SUSPENDS bool proc_mem_foll_force(struct file *file, struct mm_struct *mm)871{872	struct task_struct *task;873	bool ptrace_active = false;874 875	switch (proc_mem_force_override) {876	case PROC_MEM_FORCE_NEVER:877		return false;878	case PROC_MEM_FORCE_PTRACE:879		task = get_proc_task(file_inode(file));880		if (task) {881			ptrace_active =	READ_ONCE(task->ptrace) &&882					READ_ONCE(task->mm) == mm &&883					READ_ONCE(task->parent) == current;884			put_task_struct(task);885		}886		return ptrace_active;887	default:888		return true;889	}890}891 892static HWJS_SUSPENDS ssize_t mem_rw(struct file *file, char __user *buf,893			size_t count, loff_t *ppos, int write)894{895	struct mm_struct *mm = file->private_data;896	unsigned long addr = *ppos;897	ssize_t copied;898	char *page;899	unsigned int flags;900 901	if (!mm)902		return 0;903 904	page = (char *)__get_free_page(GFP_KERNEL);905	if (!page)906		return -ENOMEM;907 908	copied = 0;909	if (!mmget_not_zero(mm))910		goto free;911 912	flags = write ? FOLL_WRITE : 0;913	if (proc_mem_foll_force(file, mm))914		flags |= FOLL_FORCE;915 916	while (count > 0) {917		size_t this_len = min_t(size_t, count, PAGE_SIZE);918 919		if (write && copy_from_user(page, buf, this_len)) {920			copied = -EFAULT;921			break;922		}923 924		this_len = access_remote_vm(mm, addr, page, this_len, flags);925		if (!this_len) {926			if (!copied)927				copied = -EIO;928			break;929		}930 931		if (!write && copy_to_user(buf, page, this_len)) {932			copied = -EFAULT;933			break;934		}935 936		buf += this_len;937		addr += this_len;938		copied += this_len;939		count -= this_len;940	}941	*ppos = addr;942 943	mmput(mm);944free:945	free_page((unsigned long) page);946	return copied;947}948 949static HWJS_SUSPENDS ssize_t mem_read(struct file *file, char __user *buf,950			size_t count, loff_t *ppos)951{952	return mem_rw(file, buf, count, ppos, 0);953}954 955static HWJS_SUSPENDS ssize_t mem_write(struct file *file, const char __user *buf,956			 size_t count, loff_t *ppos)957{958	return mem_rw(file, (char __user*)buf, count, ppos, 1);959}960 961loff_t mem_lseek(struct file *file, loff_t offset, int orig)962{963	switch (orig) {964	case 0:965		file->f_pos = offset;966		break;967	case 1:968		file->f_pos += offset;969		break;970	default:971		return -EINVAL;972	}973	force_successful_syscall_return();974	return file->f_pos;975}976 977static int mem_release(struct inode *inode, struct file *file)978{979	struct mm_struct *mm = file->private_data;980	if (mm)981		mmdrop(mm);982	return 0;983}984 985static const struct file_operations proc_mem_operations = {986	.llseek		= mem_lseek,987	.read		= mem_read,988	.write		= mem_write,989	.open		= mem_open,990	.release	= mem_release,991	.fop_flags	= FOP_UNSIGNED_OFFSET,992};993 994static HWJS_SUSPENDS int environ_open(struct inode *inode, struct file *file)995{996	return __mem_open(inode, file, PTRACE_MODE_READ);997}998 999static ssize_t environ_read(struct file *file, char __user *buf,1000			size_t count, loff_t *ppos)1001{1002	char *page;1003	unsigned long src = *ppos;1004	int ret = 0;1005	struct mm_struct *mm = file->private_data;1006	unsigned long env_start, env_end;1007 1008	/* Ensure the process spawned far enough to have an environment. */1009	if (!mm || !mm->env_end)1010		return 0;1011 1012	page = (char *)__get_free_page(GFP_KERNEL);1013	if (!page)1014		return -ENOMEM;1015 1016	ret = 0;1017	if (!mmget_not_zero(mm))1018		goto free;1019 1020	spin_lock(&mm->arg_lock);1021	env_start = mm->env_start;1022	env_end = mm->env_end;1023	spin_unlock(&mm->arg_lock);1024 1025	while (count > 0) {1026		size_t this_len, max_len;1027		int retval;1028 1029		if (src >= (env_end - env_start))1030			break;1031 1032		this_len = env_end - (env_start + src);1033 1034		max_len = min_t(size_t, PAGE_SIZE, count);1035		this_len = min(max_len, this_len);1036 1037		retval = access_remote_vm(mm, (env_start + src), page, this_len, FOLL_ANON);1038 1039		if (retval <= 0) {1040			ret = retval;1041			break;1042		}1043 1044		if (copy_to_user(buf, page, retval)) {1045			ret = -EFAULT;1046			break;1047		}1048 1049		ret += retval;1050		src += retval;1051		buf += retval;1052		count -= retval;1053	}1054	*ppos = src;1055	mmput(mm);1056 1057free:1058	free_page((unsigned long) page);1059	return ret;1060}1061 1062static const struct file_operations proc_environ_operations = {1063	.open		= environ_open,1064	.read		= environ_read,1065	.llseek		= generic_file_llseek,1066	.release	= mem_release,1067};1068 1069static HWJS_SUSPENDS int auxv_open(struct inode *inode, struct file *file)1070{1071	return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);1072}1073 1074static ssize_t auxv_read(struct file *file, char __user *buf,1075			size_t count, loff_t *ppos)1076{1077	struct mm_struct *mm = file->private_data;1078	unsigned int nwords = 0;1079 1080	if (!mm)1081		return 0;1082	do {1083		nwords += 2;1084	} while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */1085	return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv,1086				       nwords * sizeof(mm->saved_auxv[0]));1087}1088 1089static const struct file_operations proc_auxv_operations = {1090	.open		= auxv_open,1091	.read		= auxv_read,1092	.llseek		= generic_file_llseek,1093	.release	= mem_release,1094};1095 1096static HWJS_SUSPENDS ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count,1097			    loff_t *ppos)1098{1099	struct task_struct *task = get_proc_task(file_inode(file));1100	char buffer[PROC_NUMBUF];1101	int oom_adj = OOM_ADJUST_MIN;1102	size_t len;1103 1104	if (!task)1105		return -ESRCH;1106	if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX)1107		oom_adj = OOM_ADJUST_MAX;1108	else1109		oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) /1110			  OOM_SCORE_ADJ_MAX;1111	put_task_struct(task);1112	if (oom_adj > OOM_ADJUST_MAX)1113		oom_adj = OOM_ADJUST_MAX;1114	len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj);1115	return simple_read_from_buffer(buf, count, ppos, buffer, len);1116}1117 1118static HWJS_SUSPENDS int __set_oom_adj(struct file *file, int oom_adj, bool legacy)1119{1120	struct mm_struct *mm = NULL;1121	struct task_struct *task;1122	int err = 0;1123 1124	task = get_proc_task(file_inode(file));1125	if (!task)1126		return -ESRCH;1127 1128	mutex_lock(&oom_adj_mutex);1129	if (legacy) {1130		if (oom_adj < task->signal->oom_score_adj &&1131				!capable(CAP_SYS_RESOURCE)) {1132			err = -EACCES;1133			goto err_unlock;1134		}1135		/*1136		 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use1137		 * /proc/pid/oom_score_adj instead.1138		 */1139		pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",1140			  current->comm, task_pid_nr(current), task_pid_nr(task),1141			  task_pid_nr(task));1142	} else {1143		if ((short)oom_adj < task->signal->oom_score_adj_min &&1144				!capable(CAP_SYS_RESOURCE)) {1145			err = -EACCES;1146			goto err_unlock;1147		}1148	}1149 1150	/*1151	 * Make sure we will check other processes sharing the mm if this is1152	 * not vfrok which wants its own oom_score_adj.1153	 * pin the mm so it doesn't go away and get reused after task_unlock1154	 */1155	if (!task->vfork_done) {1156		struct task_struct *p = find_lock_task_mm(task);1157 1158		if (p) {1159			if (test_bit(MMF_MULTIPROCESS, &p->mm->flags)) {1160				mm = p->mm;1161				mmgrab(mm);1162			}1163			task_unlock(p);1164		}1165	}1166 1167	task->signal->oom_score_adj = oom_adj;1168	if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))1169		task->signal->oom_score_adj_min = (short)oom_adj;1170	trace_oom_score_adj_update(task);1171 1172	if (mm) {1173		struct task_struct *p;1174 1175		rcu_read_lock();1176		for_each_process(p) {1177			if (same_thread_group(task, p))1178				continue;1179 1180			/* do not touch kernel threads or the global init */1181			if (p->flags & PF_KTHREAD || is_global_init(p))1182				continue;1183 1184			task_lock(p);1185			if (!p->vfork_done && process_shares_mm(p, mm)) {1186				p->signal->oom_score_adj = oom_adj;1187				if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))1188					p->signal->oom_score_adj_min = (short)oom_adj;1189			}1190			task_unlock(p);1191		}1192		rcu_read_unlock();1193		mmdrop(mm);1194	}1195err_unlock:1196	mutex_unlock(&oom_adj_mutex);1197	put_task_struct(task);1198	return err;1199}1200 1201/*1202 * /proc/pid/oom_adj exists solely for backwards compatibility with previous1203 * kernels.  The effective policy is defined by oom_score_adj, which has a1204 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly.1205 * Values written to oom_adj are simply mapped linearly to oom_score_adj.1206 * Processes that become oom disabled via oom_adj will still be oom disabled1207 * with this implementation.1208 *1209 * oom_adj cannot be removed since existing userspace binaries use it.1210 */1211static HWJS_SUSPENDS ssize_t oom_adj_write(struct file *file, const char __user *buf,1212			     size_t count, loff_t *ppos)1213{1214	char buffer[PROC_NUMBUF] = {};1215	int oom_adj;1216	int err;1217 1218	if (count > sizeof(buffer) - 1)1219		count = sizeof(buffer) - 1;1220	if (copy_from_user(buffer, buf, count)) {1221		err = -EFAULT;1222		goto out;1223	}1224 1225	err = kstrtoint(strstrip(buffer), 0, &oom_adj);1226	if (err)1227		goto out;1228	if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) &&1229	     oom_adj != OOM_DISABLE) {1230		err = -EINVAL;1231		goto out;1232	}1233 1234	/*1235	 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum1236	 * value is always attainable.1237	 */1238	if (oom_adj == OOM_ADJUST_MAX)1239		oom_adj = OOM_SCORE_ADJ_MAX;1240	else1241		oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE;1242 1243	err = __set_oom_adj(file, oom_adj, true);1244out:1245	return err < 0 ? err : count;1246}1247 1248static const struct file_operations proc_oom_adj_operations = {1249	.read		= oom_adj_read,1250	.write		= oom_adj_write,1251	.llseek		= generic_file_llseek,1252};1253 1254static HWJS_SUSPENDS ssize_t oom_score_adj_read(struct file *file, char __user *buf,1255					size_t count, loff_t *ppos)1256{1257	struct task_struct *task = get_proc_task(file_inode(file));1258	char buffer[PROC_NUMBUF];1259	short oom_score_adj = OOM_SCORE_ADJ_MIN;1260	size_t len;1261 1262	if (!task)1263		return -ESRCH;1264	oom_score_adj = task->signal->oom_score_adj;1265	put_task_struct(task);1266	len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj);1267	return simple_read_from_buffer(buf, count, ppos, buffer, len);1268}1269 1270static HWJS_SUSPENDS ssize_t oom_score_adj_write(struct file *file, const char __user *buf,1271					size_t count, loff_t *ppos)1272{1273	char buffer[PROC_NUMBUF] = {};1274	int oom_score_adj;1275	int err;1276 1277	if (count > sizeof(buffer) - 1)1278		count = sizeof(buffer) - 1;1279	if (copy_from_user(buffer, buf, count)) {1280		err = -EFAULT;1281		goto out;1282	}1283 1284	err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);1285	if (err)1286		goto out;1287	if (oom_score_adj < OOM_SCORE_ADJ_MIN ||1288			oom_score_adj > OOM_SCORE_ADJ_MAX) {1289		err = -EINVAL;1290		goto out;1291	}1292 1293	err = __set_oom_adj(file, oom_score_adj, false);1294out:1295	return err < 0 ? err : count;1296}1297 1298static const struct file_operations proc_oom_score_adj_operations = {1299	.read		= oom_score_adj_read,1300	.write		= oom_score_adj_write,1301	.llseek		= default_llseek,1302};1303 1304#ifdef CONFIG_AUDIT1305#define TMPBUFLEN 111306static ssize_t proc_loginuid_read(struct file * file, char __user * buf,1307				  size_t count, loff_t *ppos)1308{1309	struct inode * inode = file_inode(file);1310	struct task_struct *task = get_proc_task(inode);1311	ssize_t length;1312	char tmpbuf[TMPBUFLEN];1313 1314	if (!task)1315		return -ESRCH;1316	length = scnprintf(tmpbuf, TMPBUFLEN, "%u",1317			   from_kuid(file->f_cred->user_ns,1318				     audit_get_loginuid(task)));1319	put_task_struct(task);1320	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);1321}1322 1323static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,1324				   size_t count, loff_t *ppos)1325{1326	struct inode * inode = file_inode(file);1327	uid_t loginuid;1328	kuid_t kloginuid;1329	int rv;1330 1331	/* Don't let kthreads write their own loginuid */1332	if (current->flags & PF_KTHREAD)1333		return -EPERM;1334 1335	rcu_read_lock();1336	if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {1337		rcu_read_unlock();1338		return -EPERM;1339	}1340	rcu_read_unlock();1341 1342	if (*ppos != 0) {1343		/* No partial writes. */1344		return -EINVAL;1345	}1346 1347	rv = kstrtou32_from_user(buf, count, 10, &loginuid);1348	if (rv < 0)1349		return rv;1350 1351	/* is userspace tring to explicitly UNSET the loginuid? */1352	if (loginuid == AUDIT_UID_UNSET) {1353		kloginuid = INVALID_UID;1354	} else {1355		kloginuid = make_kuid(file->f_cred->user_ns, loginuid);1356		if (!uid_valid(kloginuid))1357			return -EINVAL;1358	}1359 1360	rv = audit_set_loginuid(kloginuid);1361	if (rv < 0)1362		return rv;1363	return count;1364}1365 1366static const struct file_operations proc_loginuid_operations = {1367	.read		= proc_loginuid_read,1368	.write		= proc_loginuid_write,1369	.llseek		= generic_file_llseek,1370};1371 1372static ssize_t proc_sessionid_read(struct file * file, char __user * buf,1373				  size_t count, loff_t *ppos)1374{1375	struct inode * inode = file_inode(file);1376	struct task_struct *task = get_proc_task(inode);1377	ssize_t length;1378	char tmpbuf[TMPBUFLEN];1379 1380	if (!task)1381		return -ESRCH;1382	length = scnprintf(tmpbuf, TMPBUFLEN, "%u",1383				audit_get_sessionid(task));1384	put_task_struct(task);1385	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);1386}1387 1388static const struct file_operations proc_sessionid_operations = {1389	.read		= proc_sessionid_read,1390	.llseek		= generic_file_llseek,1391};1392#endif1393 1394#ifdef CONFIG_FAULT_INJECTION1395static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,1396				      size_t count, loff_t *ppos)1397{1398	struct task_struct *task = get_proc_task(file_inode(file));1399	char buffer[PROC_NUMBUF];1400	size_t len;1401	int make_it_fail;1402 1403	if (!task)1404		return -ESRCH;1405	make_it_fail = task->make_it_fail;1406	put_task_struct(task);1407 1408	len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);1409 1410	return simple_read_from_buffer(buf, count, ppos, buffer, len);1411}1412 1413static ssize_t proc_fault_inject_write(struct file * file,1414			const char __user * buf, size_t count, loff_t *ppos)1415{1416	struct task_struct *task;1417	char buffer[PROC_NUMBUF] = {};1418	int make_it_fail;1419	int rv;1420 1421	if (!capable(CAP_SYS_RESOURCE))1422		return -EPERM;1423 1424	if (count > sizeof(buffer) - 1)1425		count = sizeof(buffer) - 1;1426	if (copy_from_user(buffer, buf, count))1427		return -EFAULT;1428	rv = kstrtoint(strstrip(buffer), 0, &make_it_fail);1429	if (rv < 0)1430		return rv;1431	if (make_it_fail < 0 || make_it_fail > 1)1432		return -EINVAL;1433 1434	task = get_proc_task(file_inode(file));1435	if (!task)1436		return -ESRCH;1437	task->make_it_fail = make_it_fail;1438	put_task_struct(task);1439 1440	return count;1441}1442 1443static const struct file_operations proc_fault_inject_operations = {1444	.read		= proc_fault_inject_read,1445	.write		= proc_fault_inject_write,1446	.llseek		= generic_file_llseek,1447};1448 1449static ssize_t proc_fail_nth_write(struct file *file, const char __user *buf,1450				   size_t count, loff_t *ppos)1451{1452	struct task_struct *task;1453	int err;1454	unsigned int n;1455 1456	err = kstrtouint_from_user(buf, count, 0, &n);1457	if (err)1458		return err;1459 1460	task = get_proc_task(file_inode(file));1461	if (!task)1462		return -ESRCH;1463	task->fail_nth = n;1464	put_task_struct(task);1465 1466	return count;1467}1468 1469static ssize_t proc_fail_nth_read(struct file *file, char __user *buf,1470				  size_t count, loff_t *ppos)1471{1472	struct task_struct *task;1473	char numbuf[PROC_NUMBUF];1474	ssize_t len;1475 1476	task = get_proc_task(file_inode(file));1477	if (!task)1478		return -ESRCH;1479	len = snprintf(numbuf, sizeof(numbuf), "%u\n", task->fail_nth);1480	put_task_struct(task);1481	return simple_read_from_buffer(buf, count, ppos, numbuf, len);1482}1483 1484static const struct file_operations proc_fail_nth_operations = {1485	.read		= proc_fail_nth_read,1486	.write		= proc_fail_nth_write,1487};1488#endif1489 1490 1491#ifdef CONFIG_SCHED_DEBUG1492/*1493 * Print out various scheduling related per-task fields:1494 */1495static int sched_show(struct seq_file *m, void *v)1496{1497	struct inode *inode = m->private;1498	struct pid_namespace *ns = proc_pid_ns(inode->i_sb);1499	struct task_struct *p;1500 1501	p = get_proc_task(inode);1502	if (!p)1503		return -ESRCH;1504	proc_sched_show_task(p, ns, m);1505 1506	put_task_struct(p);1507 1508	return 0;1509}1510 1511static ssize_t1512sched_write(struct file *file, const char __user *buf,1513	    size_t count, loff_t *offset)1514{1515	struct inode *inode = file_inode(file);1516	struct task_struct *p;1517 1518	p = get_proc_task(inode);1519	if (!p)1520		return -ESRCH;1521	proc_sched_set_task(p);1522 1523	put_task_struct(p);1524 1525	return count;1526}1527 1528static int sched_open(struct inode *inode, struct file *filp)1529{1530	return single_open(filp, sched_show, inode);1531}1532 1533static const struct file_operations proc_pid_sched_operations = {1534	.open		= sched_open,1535	.read		= seq_read,1536	.write		= sched_write,1537	.llseek		= seq_lseek,1538	.release	= single_release,1539};1540 1541#endif1542 1543#ifdef CONFIG_SCHED_AUTOGROUP1544/*1545 * Print out autogroup related information:1546 */1547static int sched_autogroup_show(struct seq_file *m, void *v)1548{1549	struct inode *inode = m->private;1550	struct task_struct *p;1551 1552	p = get_proc_task(inode);1553	if (!p)1554		return -ESRCH;1555	proc_sched_autogroup_show_task(p, m);1556 1557	put_task_struct(p);1558 1559	return 0;1560}1561 1562static ssize_t1563sched_autogroup_write(struct file *file, const char __user *buf,1564	    size_t count, loff_t *offset)1565{1566	struct inode *inode = file_inode(file);1567	struct task_struct *p;1568	char buffer[PROC_NUMBUF] = {};1569	int nice;1570	int err;1571 1572	if (count > sizeof(buffer) - 1)1573		count = sizeof(buffer) - 1;1574	if (copy_from_user(buffer, buf, count))1575		return -EFAULT;1576 1577	err = kstrtoint(strstrip(buffer), 0, &nice);1578	if (err < 0)1579		return err;1580 1581	p = get_proc_task(inode);1582	if (!p)1583		return -ESRCH;1584 1585	err = proc_sched_autogroup_set_nice(p, nice);1586	if (err)1587		count = err;1588 1589	put_task_struct(p);1590 1591	return count;1592}1593 1594static int sched_autogroup_open(struct inode *inode, struct file *filp)1595{1596	int ret;1597 1598	ret = single_open(filp, sched_autogroup_show, NULL);1599	if (!ret) {1600		struct seq_file *m = filp->private_data;1601 1602		m->private = inode;1603	}1604	return ret;1605}1606 1607static const struct file_operations proc_pid_sched_autogroup_operations = {1608	.open		= sched_autogroup_open,1609	.read		= seq_read,1610	.write		= sched_autogroup_write,1611	.llseek		= seq_lseek,1612	.release	= single_release,1613};1614 1615#endif /* CONFIG_SCHED_AUTOGROUP */1616 1617#ifdef CONFIG_TIME_NS1618static int timens_offsets_show(struct seq_file *m, void *v)1619{1620	struct task_struct *p;1621 1622	p = get_proc_task(file_inode(m->file));1623	if (!p)1624		return -ESRCH;1625	proc_timens_show_offsets(p, m);1626 1627	put_task_struct(p);1628 1629	return 0;1630}1631 1632static ssize_t timens_offsets_write(struct file *file, const char __user *buf,1633				    size_t count, loff_t *ppos)1634{1635	struct inode *inode = file_inode(file);1636	struct proc_timens_offset offsets[2];1637	char *kbuf = NULL, *pos, *next_line;1638	struct task_struct *p;1639	int ret, noffsets;1640 1641	/* Only allow < page size writes at the beginning of the file */1642	if ((*ppos != 0) || (count >= PAGE_SIZE))1643		return -EINVAL;1644 1645	/* Slurp in the user data */1646	kbuf = memdup_user_nul(buf, count);1647	if (IS_ERR(kbuf))1648		return PTR_ERR(kbuf);1649 1650	/* Parse the user data */1651	ret = -EINVAL;1652	noffsets = 0;1653	for (pos = kbuf; pos; pos = next_line) {1654		struct proc_timens_offset *off = &offsets[noffsets];1655		char clock[10];1656		int err;1657 1658		/* Find the end of line and ensure we don't look past it */1659		next_line = strchr(pos, '\n');1660		if (next_line) {1661			*next_line = '\0';1662			next_line++;1663			if (*next_line == '\0')1664				next_line = NULL;1665		}1666 1667		err = sscanf(pos, "%9s %lld %lu", clock,1668				&off->val.tv_sec, &off->val.tv_nsec);1669		if (err != 3 || off->val.tv_nsec >= NSEC_PER_SEC)1670			goto out;1671 1672		clock[sizeof(clock) - 1] = 0;1673		if (strcmp(clock, "monotonic") == 0 ||1674		    strcmp(clock, __stringify(CLOCK_MONOTONIC)) == 0)1675			off->clockid = CLOCK_MONOTONIC;1676		else if (strcmp(clock, "boottime") == 0 ||1677			 strcmp(clock, __stringify(CLOCK_BOOTTIME)) == 0)1678			off->clockid = CLOCK_BOOTTIME;1679		else1680			goto out;1681 1682		noffsets++;1683		if (noffsets == ARRAY_SIZE(offsets)) {1684			if (next_line)1685				count = next_line - kbuf;1686			break;1687		}1688	}1689 1690	ret = -ESRCH;1691	p = get_proc_task(inode);1692	if (!p)1693		goto out;1694	ret = proc_timens_set_offset(file, p, offsets, noffsets);1695	put_task_struct(p);1696	if (ret)1697		goto out;1698 1699	ret = count;1700out:1701	kfree(kbuf);1702	return ret;1703}1704 1705static int timens_offsets_open(struct inode *inode, struct file *filp)1706{1707	return single_open(filp, timens_offsets_show, inode);1708}1709 1710static const struct file_operations proc_timens_offsets_operations = {1711	.open		= timens_offsets_open,1712	.read		= seq_read,1713	.write		= timens_offsets_write,1714	.llseek		= seq_lseek,1715	.release	= single_release,1716};1717#endif /* CONFIG_TIME_NS */1718 1719static ssize_t comm_write(struct file *file, const char __user *buf,1720				size_t count, loff_t *offset)1721{1722	struct inode *inode = file_inode(file);1723	struct task_struct *p;1724	char buffer[TASK_COMM_LEN] = {};1725	const size_t maxlen = sizeof(buffer) - 1;1726 1727	if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count))1728		return -EFAULT;1729 1730	p = get_proc_task(inode);1731	if (!p)1732		return -ESRCH;1733 1734	if (same_thread_group(current, p)) {1735		set_task_comm(p, buffer);1736		proc_comm_connector(p);1737	}1738	else1739		count = -EINVAL;1740 1741	put_task_struct(p);1742 1743	return count;1744}1745 1746static HWJS_SUSPENDS int comm_show(struct seq_file *m, void *v)1747{1748	struct inode *inode = m->private;1749	struct task_struct *p;1750 1751	p = get_proc_task(inode);1752	if (!p)1753		return -ESRCH;1754 1755	proc_task_name(m, p, false);1756	seq_putc(m, '\n');1757 1758	put_task_struct(p);1759 1760	return 0;1761}1762 1763static int comm_open(struct inode *inode, struct file *filp)1764{1765	return single_open(filp, comm_show, inode);1766}1767 1768static const struct file_operations proc_pid_set_comm_operations = {1769	.open		= comm_open,1770	.read		= seq_read,1771	.write		= comm_write,1772	.llseek		= seq_lseek,1773	.release	= single_release,1774};1775 1776static HWJS_SUSPENDS int proc_exe_link(struct dentry *dentry, struct path *exe_path)1777{1778	struct task_struct *task;1779	struct file *exe_file;1780 1781	task = get_proc_task(d_inode(dentry));1782	if (!task)1783		return -ENOENT;1784	exe_file = get_task_exe_file(task);1785	put_task_struct(task);1786	if (exe_file) {1787		*exe_path = exe_file->f_path;1788		path_get(&exe_file->f_path);1789		fput(exe_file);1790		return 0;1791	} else1792		return -ENOENT;1793}1794 1795static HWJS_SUSPENDS const char *proc_pid_get_link(struct dentry *dentry,1796				     struct inode *inode,1797				     struct delayed_call *done)1798{1799	struct path path;1800	int error = -EACCES;1801 1802	if (!dentry)1803		return ERR_PTR(-ECHILD);1804 1805	/* Are we allowed to snoop on the tasks file descriptors? */1806	if (!proc_fd_access_allowed(inode))1807		goto out;1808 1809	error = PROC_I(inode)->op.proc_get_link(dentry, &path);1810	if (error)1811		goto out;1812 1813	error = nd_jump_link(&path);1814out:1815	return ERR_PTR(error);1816}1817 1818static int do_proc_readlink(const struct path *path, char __user *buffer, int buflen)1819{1820	char *tmp = kmalloc(PATH_MAX, GFP_KERNEL);1821	char *pathname;1822	int len;1823 1824	if (!tmp)1825		return -ENOMEM;1826 1827	pathname = d_path(path, tmp, PATH_MAX);1828	len = PTR_ERR(pathname);1829	if (IS_ERR(pathname))1830		goto out;1831	len = tmp + PATH_MAX - 1 - pathname;1832 1833	if (len > buflen)1834		len = buflen;1835	if (copy_to_user(buffer, pathname, len))1836		len = -EFAULT;1837 out:1838	kfree(tmp);1839	return len;1840}1841 1842static HWJS_SUSPENDS int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)1843{1844	int error = -EACCES;1845	struct inode *inode = d_inode(dentry);1846	struct path path;1847 1848	/* Are we allowed to snoop on the tasks file descriptors? */1849	if (!proc_fd_access_allowed(inode))1850		goto out;1851 1852	error = PROC_I(inode)->op.proc_get_link(dentry, &path);1853	if (error)1854		goto out;1855 1856	error = do_proc_readlink(&path, buffer, buflen);1857	path_put(&path);1858out:1859	return error;1860}1861 1862const struct inode_operations proc_pid_link_inode_operations = {1863	.readlink	= proc_pid_readlink,1864	.get_link	= proc_pid_get_link,1865	.setattr	= proc_setattr,1866};1867 1868 1869/* building an inode */1870 1871void task_dump_owner(struct task_struct *task, umode_t mode,1872		     kuid_t *ruid, kgid_t *rgid)1873{1874	/* Depending on the state of dumpable compute who should own a1875	 * proc file for a task.1876	 */1877	const struct cred *cred;1878	kuid_t uid;1879	kgid_t gid;1880 1881	if (unlikely(task->flags & PF_KTHREAD)) {1882		*ruid = GLOBAL_ROOT_UID;1883		*rgid = GLOBAL_ROOT_GID;1884		return;1885	}1886 1887	/* Default to the tasks effective ownership */1888	rcu_read_lock();1889	cred = __task_cred(task);1890	uid = cred->euid;1891	gid = cred->egid;1892	rcu_read_unlock();1893 1894	/*1895	 * Before the /proc/pid/status file was created the only way to read1896	 * the effective uid of a /process was to stat /proc/pid.  Reading1897	 * /proc/pid/status is slow enough that procps and other packages1898	 * kept stating /proc/pid.  To keep the rules in /proc simple I have1899	 * made this apply to all per process world readable and executable1900	 * directories.1901	 */1902	if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) {1903		struct mm_struct *mm;1904		task_lock(task);1905		mm = task->mm;1906		/* Make non-dumpable tasks owned by some root */1907		if (mm) {1908			if (get_dumpable(mm) != SUID_DUMP_USER) {1909				struct user_namespace *user_ns = mm->user_ns;1910 1911				uid = make_kuid(user_ns, 0);1912				if (!uid_valid(uid))1913					uid = GLOBAL_ROOT_UID;1914 1915				gid = make_kgid(user_ns, 0);1916				if (!gid_valid(gid))1917					gid = GLOBAL_ROOT_GID;1918			}1919		} else {1920			uid = GLOBAL_ROOT_UID;1921			gid = GLOBAL_ROOT_GID;1922		}1923		task_unlock(task);1924	}1925	*ruid = uid;1926	*rgid = gid;1927}1928 1929void proc_pid_evict_inode(struct proc_inode *ei)1930{1931	struct pid *pid = ei->pid;1932 1933	if (S_ISDIR(ei->vfs_inode.i_mode)) {1934		spin_lock(&pid->lock);1935		hlist_del_init_rcu(&ei->sibling_inodes);1936		spin_unlock(&pid->lock);1937	}1938}1939 1940struct inode *proc_pid_make_inode(struct super_block *sb,1941				  struct task_struct *task, umode_t mode)1942{1943	struct inode * inode;1944	struct proc_inode *ei;1945	struct pid *pid;1946 1947	/* We need a new inode */1948 1949	inode = new_inode(sb);1950	if (!inode)1951		goto out;1952 1953	/* Common stuff */1954	ei = PROC_I(inode);1955	inode->i_mode = mode;1956	inode->i_ino = get_next_ino();1957	simple_inode_init_ts(inode);1958	inode->i_op = &proc_def_inode_operations;1959 1960	/*1961	 * grab the reference to task.1962	 */1963	pid = get_task_pid(task, PIDTYPE_PID);1964	if (!pid)1965		goto out_unlock;1966 1967	/* Let the pid remember us for quick removal */1968	ei->pid = pid;1969 1970	task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);1971	security_task_to_inode(task, inode);1972 1973out:1974	return inode;1975 1976out_unlock:1977	iput(inode);1978	return NULL;1979}1980 1981/*1982 * Generating an inode and adding it into @pid->inodes, so that task will1983 * invalidate inode's dentry before being released.1984 *1985 * This helper is used for creating dir-type entries under '/proc' and1986 * '/proc/<tgid>/task'. Other entries(eg. fd, stat) under '/proc/<tgid>'1987 * can be released by invalidating '/proc/<tgid>' dentry.1988 * In theory, dentries under '/proc/<tgid>/task' can also be released by1989 * invalidating '/proc/<tgid>' dentry, we reserve it to handle single1990 * thread exiting situation: Any one of threads should invalidate its1991 * '/proc/<tgid>/task/<pid>' dentry before released.1992 */1993static HWJS_SUSPENDS struct inode *proc_pid_make_base_inode(struct super_block *sb,1994				struct task_struct *task, umode_t mode)1995{1996	struct inode *inode;1997	struct proc_inode *ei;1998	struct pid *pid;1999 2000	inode = proc_pid_make_inode(sb, task, mode);2001	if (!inode)2002		return NULL;2003 2004	/* Let proc_flush_pid find this directory inode */2005	ei = PROC_I(inode);2006	pid = ei->pid;2007	spin_lock(&pid->lock);2008	hlist_add_head_rcu(&ei->sibling_inodes, &pid->inodes);2009	spin_unlock(&pid->lock);2010 2011	return inode;2012}2013 2014int pid_getattr(struct mnt_idmap *idmap, const struct path *path,2015		struct kstat *stat, u32 request_mask, unsigned int query_flags)2016{2017	struct inode *inode = d_inode(path->dentry);2018	struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb);2019	struct task_struct *task;2020 2021	generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);2022 2023	stat->uid = GLOBAL_ROOT_UID;2024	stat->gid = GLOBAL_ROOT_GID;2025	rcu_read_lock();2026	task = pid_task(proc_pid(inode), PIDTYPE_PID);2027	if (task) {2028		if (!has_pid_permissions(fs_info, task, HIDEPID_INVISIBLE)) {2029			rcu_read_unlock();2030			/*2031			 * This doesn't prevent learning whether PID exists,2032			 * it only makes getattr() consistent with readdir().2033			 */2034			return -ENOENT;2035		}2036		task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid);2037	}2038	rcu_read_unlock();2039	return 0;2040}2041 2042/* dentry stuff */2043 2044/*2045 * Set <pid>/... inode ownership (can change due to setuid(), etc.)2046 */2047void pid_update_inode(struct task_struct *task, struct inode *inode)2048{2049	task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid);2050 2051	inode->i_mode &= ~(S_ISUID | S_ISGID);2052	security_task_to_inode(task, inode);2053}2054 2055/*2056 * Rewrite the inode's ownerships here because the owning task may have2057 * performed a setuid(), etc.2058 *2059 */2060static int pid_revalidate(struct dentry *dentry, unsigned int flags)2061{2062	struct inode *inode;2063	struct task_struct *task;2064	int ret = 0;2065 2066	rcu_read_lock();2067	inode = d_inode_rcu(dentry);2068	if (!inode)2069		goto out;2070	task = pid_task(proc_pid(inode), PIDTYPE_PID);2071 2072	if (task) {2073		pid_update_inode(task, inode);2074		ret = 1;2075	}2076out:2077	rcu_read_unlock();2078	return ret;2079}2080 2081static inline bool proc_inode_is_dead(struct inode *inode)2082{2083	return !proc_pid(inode)->tasks[PIDTYPE_PID].first;2084}2085 2086int pid_delete_dentry(const struct dentry *dentry)2087{2088	/* Is the task we represent dead?2089	 * If so, then don't put the dentry on the lru list,2090	 * kill it immediately.2091	 */2092	return proc_inode_is_dead(d_inode(dentry));2093}2094 2095const struct dentry_operations pid_dentry_operations =2096{2097	.d_revalidate	= pid_revalidate,2098	.d_delete	= pid_delete_dentry,2099};2100 2101/* Lookups */2102 2103/*2104 * Fill a directory entry.2105 *2106 * If possible create the dcache entry and derive our inode number and2107 * file type from dcache entry.2108 *2109 * Since all of the proc inode numbers are dynamically generated, the inode2110 * numbers do not exist until the inode is cache.  This means creating2111 * the dcache entry in readdir is necessary to keep the inode numbers2112 * reported by readdir in sync with the inode numbers reported2113 * by stat.2114 */2115bool proc_fill_cache(struct file *file, struct dir_context *ctx,2116	const char *name, unsigned int len,2117	instantiate_t instantiate, struct task_struct *task, const void *ptr)2118{2119	struct dentry *child, *dir = file->f_path.dentry;2120	struct qstr qname = QSTR_INIT(name, len);2121	struct inode *inode;2122	unsigned type = DT_UNKNOWN;2123	ino_t ino = 1;2124 2125	child = d_hash_and_lookup(dir, &qname);2126	if (!child) {2127		DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);2128		child = d_alloc_parallel(dir, &qname, &wq);2129		if (IS_ERR(child))2130			goto end_instantiate;2131		if (d_in_lookup(child)) {2132			struct dentry *res;2133			res = instantiate(child, task, ptr);2134			d_lookup_done(child);2135			if (unlikely(res)) {2136				dput(child);2137				child = res;2138				if (IS_ERR(child))2139					goto end_instantiate;2140			}2141		}2142	}2143	inode = d_inode(child);2144	ino = inode->i_ino;2145	type = inode->i_mode >> 12;2146	dput(child);2147end_instantiate:2148	return dir_emit(ctx, name, len, ino, type);2149}2150 2151/*2152 * dname_to_vma_addr - maps a dentry name into two unsigned longs2153 * which represent vma start and end addresses.2154 */2155static int dname_to_vma_addr(struct dentry *dentry,2156			     unsigned long *start, unsigned long *end)2157{2158	const char *str = dentry->d_name.name;2159	unsigned long long sval, eval;2160	unsigned int len;2161 2162	if (str[0] == '0' && str[1] != '-')2163		return -EINVAL;2164	len = _parse_integer(str, 16, &sval);2165	if (len & KSTRTOX_OVERFLOW)2166		return -EINVAL;2167	if (sval != (unsigned long)sval)2168		return -EINVAL;2169	str += len;2170 2171	if (*str != '-')2172		return -EINVAL;2173	str++;2174 2175	if (str[0] == '0' && str[1])2176		return -EINVAL;2177	len = _parse_integer(str, 16, &eval);2178	if (len & KSTRTOX_OVERFLOW)2179		return -EINVAL;2180	if (eval != (unsigned long)eval)2181		return -EINVAL;2182	str += len;2183 2184	if (*str != '\0')2185		return -EINVAL;2186 2187	*start = sval;2188	*end = eval;2189 2190	return 0;2191}2192 2193static HWJS_SUSPENDS int map_files_d_revalidate(struct dentry *dentry, unsigned int flags)2194{2195	unsigned long vm_start, vm_end;2196	bool exact_vma_exists = false;2197	struct mm_struct *mm = NULL;2198	struct task_struct *task;2199	struct inode *inode;2200	int status = 0;2201 2202	if (flags & LOOKUP_RCU)2203		return -ECHILD;2204 2205	inode = d_inode(dentry);2206	task = get_proc_task(inode);2207	if (!task)2208		goto out_notask;2209 2210	mm = mm_access(task, PTRACE_MODE_READ_FSCREDS);2211	if (IS_ERR_OR_NULL(mm))2212		goto out;2213 2214	if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {2215		status = mmap_read_lock_killable(mm);2216		if (!status) {2217			exact_vma_exists = !!find_exact_vma(mm, vm_start,2218							    vm_end);2219			mmap_read_unlock(mm);2220		}2221	}2222 2223	mmput(mm);2224 2225	if (exact_vma_exists) {2226		task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);2227 2228		security_task_to_inode(task, inode);2229		status = 1;2230	}2231 2232out:2233	put_task_struct(task);2234 2235out_notask:2236	return status;2237}2238 2239static const struct dentry_operations tid_map_files_dentry_operations = {2240	.d_revalidate	= map_files_d_revalidate,2241	.d_delete	= pid_delete_dentry,2242};2243 2244static HWJS_SUSPENDS int map_files_get_link(struct dentry *dentry, struct path *path)2245{2246	unsigned long vm_start, vm_end;2247	struct vm_area_struct *vma;2248	struct task_struct *task;2249	struct mm_struct *mm;2250	int rc;2251 2252	rc = -ENOENT;2253	task = get_proc_task(d_inode(dentry));2254	if (!task)2255		goto out;2256 2257	mm = get_task_mm(task);2258	put_task_struct(task);2259	if (!mm)2260		goto out;2261 2262	rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);2263	if (rc)2264		goto out_mmput;2265 2266	rc = mmap_read_lock_killable(mm);2267	if (rc)2268		goto out_mmput;2269 2270	rc = -ENOENT;2271	vma = find_exact_vma(mm, vm_start, vm_end);2272	if (vma && vma->vm_file) {2273		*path = *file_user_path(vma->vm_file);2274		path_get(path);2275		rc = 0;2276	}2277	mmap_read_unlock(mm);2278 2279out_mmput:2280	mmput(mm);2281out:2282	return rc;2283}2284 2285struct map_files_info {2286	unsigned long	start;2287	unsigned long	end;2288	fmode_t		mode;2289};2290 2291/*2292 * Only allow CAP_SYS_ADMIN and CAP_CHECKPOINT_RESTORE to follow the links, due2293 * to concerns about how the symlinks may be used to bypass permissions on2294 * ancestor directories in the path to the file in question.2295 */2296static HWJS_SUSPENDS const char *2297proc_map_files_get_link(struct dentry *dentry,2298			struct inode *inode,2299		        struct delayed_call *done)2300{2301	if (!checkpoint_restore_ns_capable(&init_user_ns))2302		return ERR_PTR(-EPERM);2303 2304	return proc_pid_get_link(dentry, inode, done);2305}2306 2307/*2308 * Identical to proc_pid_link_inode_operations except for get_link()2309 */2310static const struct inode_operations proc_map_files_link_inode_operations = {2311	.readlink	= proc_pid_readlink,2312	.get_link	= proc_map_files_get_link,2313	.setattr	= proc_setattr,2314};2315 2316static HWJS_SUSPENDS struct dentry *2317proc_map_files_instantiate(struct dentry *dentry,2318			   struct task_struct *task, const void *ptr)2319{2320	fmode_t mode = (fmode_t)(unsigned long)ptr;2321	struct proc_inode *ei;2322	struct inode *inode;2323 2324	inode = proc_pid_make_inode(dentry->d_sb, task, S_IFLNK |2325				    ((mode & FMODE_READ ) ? S_IRUSR : 0) |2326				    ((mode & FMODE_WRITE) ? S_IWUSR : 0));2327	if (!inode)2328		return ERR_PTR(-ENOENT);2329 2330	ei = PROC_I(inode);2331	ei->op.proc_get_link = map_files_get_link;2332 2333	inode->i_op = &proc_map_files_link_inode_operations;2334	inode->i_size = 64;2335 2336	return proc_splice_unmountable(inode, dentry,2337				       &tid_map_files_dentry_operations);2338}2339 2340static HWJS_SUSPENDS struct dentry *proc_map_files_lookup(struct inode *dir,2341		struct dentry *dentry, unsigned int flags)2342{2343	unsigned long vm_start, vm_end;2344	struct vm_area_struct *vma;2345	struct task_struct *task;2346	struct dentry *result;2347	struct mm_struct *mm;2348 2349	result = ERR_PTR(-ENOENT);2350	task = get_proc_task(dir);2351	if (!task)2352		goto out;2353 2354	result = ERR_PTR(-EACCES);2355	if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))2356		goto out_put_task;2357 2358	result = ERR_PTR(-ENOENT);2359	if (dname_to_vma_addr(dentry, &vm_start, &vm_end))2360		goto out_put_task;2361 2362	mm = get_task_mm(task);2363	if (!mm)2364		goto out_put_task;2365 2366	result = ERR_PTR(-EINTR);2367	if (mmap_read_lock_killable(mm))2368		goto out_put_mm;2369 2370	result = ERR_PTR(-ENOENT);2371	vma = find_exact_vma(mm, vm_start, vm_end);2372	if (!vma)2373		goto out_no_vma;2374 2375	if (vma->vm_file)2376		result = proc_map_files_instantiate(dentry, task,2377				(void *)(unsigned long)vma->vm_file->f_mode);2378 2379out_no_vma:2380	mmap_read_unlock(mm);2381out_put_mm:2382	mmput(mm);2383out_put_task:2384	put_task_struct(task);2385out:2386	return result;2387}2388 2389static const struct inode_operations proc_map_files_inode_operations = {2390	.lookup		= proc_map_files_lookup,2391	.permission	= proc_fd_permission,2392	.setattr	= proc_setattr,2393};2394 2395static HWJS_SUSPENDS int2396proc_map_files_readdir(struct file *file, struct dir_context *ctx)2397{2398	struct vm_area_struct *vma;2399	struct task_struct *task;2400	struct mm_struct *mm;2401	unsigned long nr_files, pos, i;2402	GENRADIX(struct map_files_info) fa;2403	struct map_files_info *p;2404	int ret;2405	struct vma_iterator vmi;2406 2407	genradix_init(&fa);2408 2409	ret = -ENOENT;2410	task = get_proc_task(file_inode(file));2411	if (!task)2412		goto out;2413 2414	ret = -EACCES;2415	if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))2416		goto out_put_task;2417 2418	ret = 0;2419	if (!dir_emit_dots(file, ctx))2420		goto out_put_task;2421 2422	mm = get_task_mm(task);2423	if (!mm)2424		goto out_put_task;2425 2426	ret = mmap_read_lock_killable(mm);2427	if (ret) {2428		mmput(mm);2429		goto out_put_task;2430	}2431 2432	nr_files = 0;2433 2434	/*2435	 * We need two passes here:2436	 *2437	 *  1) Collect vmas of mapped files with mmap_lock taken2438	 *  2) Release mmap_lock and instantiate entries2439	 *2440	 * otherwise we get lockdep complained, since filldir()2441	 * routine might require mmap_lock taken in might_fault().2442	 */2443 2444	pos = 2;2445	vma_iter_init(&vmi, mm, 0);2446	for_each_vma(vmi, vma) {2447		if (!vma->vm_file)2448			continue;2449		if (++pos <= ctx->pos)2450			continue;2451 2452		p = genradix_ptr_alloc(&fa, nr_files++, GFP_KERNEL);2453		if (!p) {2454			ret = -ENOMEM;2455			mmap_read_unlock(mm);2456			mmput(mm);2457			goto out_put_task;2458		}2459 2460		p->start = vma->vm_start;2461		p->end = vma->vm_end;2462		p->mode = vma->vm_file->f_mode;2463	}2464	mmap_read_unlock(mm);2465	mmput(mm);2466 2467	for (i = 0; i < nr_files; i++) {2468		char buf[4 * sizeof(long) + 2];	/* max: %lx-%lx\0 */2469		unsigned int len;2470 2471		p = genradix_ptr(&fa, i);2472		len = snprintf(buf, sizeof(buf), "%lx-%lx", p->start, p->end);2473		if (!proc_fill_cache(file, ctx,2474				      buf, len,2475				      proc_map_files_instantiate,2476				      task,2477				      (void *)(unsigned long)p->mode))2478			break;2479		ctx->pos++;2480	}2481 2482out_put_task:2483	put_task_struct(task);2484out:2485	genradix_free(&fa);2486	return ret;2487}2488 2489static const struct file_operations proc_map_files_operations = {2490	.read		= generic_read_dir,2491	.iterate_shared	= proc_map_files_readdir,2492	.llseek		= generic_file_llseek,2493};2494 2495#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)2496struct timers_private {2497	struct pid *pid;2498	struct task_struct *task;2499	struct sighand_struct *sighand;2500	struct pid_namespace *ns;2501	unsigned long flags;2502};2503 2504static void *timers_start(struct seq_file *m, loff_t *pos)2505{2506	struct timers_private *tp = m->private;2507 2508	tp->task = get_pid_task(tp->pid, PIDTYPE_PID);2509	if (!tp->task)2510		return ERR_PTR(-ESRCH);2511 2512	tp->sighand = lock_task_sighand(tp->task, &tp->flags);2513	if (!tp->sighand)2514		return ERR_PTR(-ESRCH);2515 2516	return seq_hlist_start(&tp->task->signal->posix_timers, *pos);2517}2518 2519static void *timers_next(struct seq_file *m, void *v, loff_t *pos)2520{2521	struct timers_private *tp = m->private;2522	return seq_hlist_next(v, &tp->task->signal->posix_timers, pos);2523}2524 2525static void timers_stop(struct seq_file *m, void *v)2526{2527	struct timers_private *tp = m->private;2528 2529	if (tp->sighand) {2530		unlock_task_sighand(tp->task, &tp->flags);2531		tp->sighand = NULL;2532	}2533 2534	if (tp->task) {2535		put_task_struct(tp->task);2536		tp->task = NULL;2537	}2538}2539 2540static int show_timer(struct seq_file *m, void *v)2541{2542	struct k_itimer *timer;2543	struct timers_private *tp = m->private;2544	int notify;2545	static const char * const nstr[] = {2546		[SIGEV_SIGNAL] = "signal",2547		[SIGEV_NONE] = "none",2548		[SIGEV_THREAD] = "thread",2549	};2550 2551	timer = hlist_entry((struct hlist_node *)v, struct k_itimer, list);2552	notify = timer->it_sigev_notify;2553 2554	seq_printf(m, "ID: %d\n", timer->it_id);2555	seq_printf(m, "signal: %d/%px\n",2556		   timer->sigq->info.si_signo,2557		   timer->sigq->info.si_value.sival_ptr);2558	seq_printf(m, "notify: %s/%s.%d\n",2559		   nstr[notify & ~SIGEV_THREAD_ID],2560		   (notify & SIGEV_THREAD_ID) ? "tid" : "pid",2561		   pid_nr_ns(timer->it_pid, tp->ns));2562	seq_printf(m, "ClockID: %d\n", timer->it_clock);2563 2564	return 0;2565}2566 2567static const struct seq_operations proc_timers_seq_ops = {2568	.start	= timers_start,2569	.next	= timers_next,2570	.stop	= timers_stop,2571	.show	= show_timer,2572};2573 2574static int proc_timers_open(struct inode *inode, struct file *file)2575{2576	struct timers_private *tp;2577 2578	tp = __seq_open_private(file, &proc_timers_seq_ops,2579			sizeof(struct timers_private));2580	if (!tp)2581		return -ENOMEM;2582 2583	tp->pid = proc_pid(inode);2584	tp->ns = proc_pid_ns(inode->i_sb);2585	return 0;2586}2587 2588static const struct file_operations proc_timers_operations = {2589	.open		= proc_timers_open,2590	.read		= seq_read,2591	.llseek		= seq_lseek,2592	.release	= seq_release_private,2593};2594#endif2595 2596static ssize_t timerslack_ns_write(struct file *file, const char __user *buf,2597					size_t count, loff_t *offset)2598{2599	struct inode *inode = file_inode(file);2600	struct task_struct *p;2601	u64 slack_ns;2602	int err;2603 2604	err = kstrtoull_from_user(buf, count, 10, &slack_ns);2605	if (err < 0)2606		return err;2607 2608	p = get_proc_task(inode);2609	if (!p)2610		return -ESRCH;2611 2612	if (p != current) {2613		rcu_read_lock();2614		if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {2615			rcu_read_unlock();2616			count = -EPERM;2617			goto out;2618		}2619		rcu_read_unlock();2620 2621		err = security_task_setscheduler(p);2622		if (err) {2623			count = err;2624			goto out;2625		}2626	}2627 2628	task_lock(p);2629	if (rt_or_dl_task_policy(p))2630		slack_ns = 0;2631	else if (slack_ns == 0)2632		slack_ns = p->default_timer_slack_ns;2633	p->timer_slack_ns = slack_ns;2634	task_unlock(p);2635 2636out:2637	put_task_struct(p);2638 2639	return count;2640}2641 2642static HWJS_SUSPENDS int timerslack_ns_show(struct seq_file *m, void *v)2643{2644	struct inode *inode = m->private;2645	struct task_struct *p;2646	int err = 0;2647 2648	p = get_proc_task(inode);2649	if (!p)2650		return -ESRCH;2651 2652	if (p != current) {2653		rcu_read_lock();2654		if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {2655			rcu_read_unlock();2656			err = -EPERM;2657			goto out;2658		}2659		rcu_read_unlock();2660 2661		err = security_task_getscheduler(p);2662		if (err)2663			goto out;2664	}2665 2666	task_lock(p);2667	seq_printf(m, "%llu\n", p->timer_slack_ns);2668	task_unlock(p);2669 2670out:2671	put_task_struct(p);2672 2673	return err;2674}2675 2676static int timerslack_ns_open(struct inode *inode, struct file *filp)2677{2678	return single_open(filp, timerslack_ns_show, inode);2679}2680 2681static const struct file_operations proc_pid_set_timerslack_ns_operations = {2682	.open		= timerslack_ns_open,2683	.read		= seq_read,2684	.write		= timerslack_ns_write,2685	.llseek		= seq_lseek,2686	.release	= single_release,2687};2688 2689static HWJS_SUSPENDS struct dentry *proc_pident_instantiate(struct dentry *dentry,2690	struct task_struct *task, const void *ptr)2691{2692	const struct pid_entry *p = ptr;2693	struct inode *inode;2694	struct proc_inode *ei;2695 2696	inode = proc_pid_make_inode(dentry->d_sb, task, p->mode);2697	if (!inode)2698		return ERR_PTR(-ENOENT);2699 2700	ei = PROC_I(inode);2701	if (S_ISDIR(inode->i_mode))2702		set_nlink(inode, 2);	/* Use getattr to fix if necessary */2703	if (p->iop)2704		inode->i_op = p->iop;2705	if (p->fop)2706		inode->i_fop = p->fop;2707	ei->op = p->op;2708	pid_update_inode(task, inode);2709	d_set_d_op(dentry, &pid_dentry_operations);2710	return d_splice_alias(inode, dentry);2711}2712 2713static HWJS_SUSPENDS struct dentry *proc_pident_lookup(struct inode *dir, 2714					 struct dentry *dentry,2715					 const struct pid_entry *p,2716					 const struct pid_entry *end)2717{2718	struct task_struct *task = get_proc_task(dir);2719	struct dentry *res = ERR_PTR(-ENOENT);2720 2721	if (!task)2722		goto out_no_task;2723 2724	/*2725	 * Yes, it does not scale. And it should not. Don't add2726	 * new entries into /proc/<tgid>/ without very good reasons.2727	 */2728	for (; p < end; p++) {2729		if (p->len != dentry->d_name.len)2730			continue;2731		if (!memcmp(dentry->d_name.name, p->name, p->len)) {2732			res = proc_pident_instantiate(dentry, task, p);2733			break;2734		}2735	}2736	put_task_struct(task);2737out_no_task:2738	return res;2739}2740 2741static HWJS_SUSPENDS int proc_pident_readdir(struct file *file, struct dir_context *ctx,2742		const struct pid_entry *ents, unsigned int nents)2743{2744	struct task_struct *task = get_proc_task(file_inode(file));2745	const struct pid_entry *p;2746 2747	if (!task)2748		return -ENOENT;2749 2750	if (!dir_emit_dots(file, ctx))2751		goto out;2752 2753	if (ctx->pos >= nents + 2)2754		goto out;2755 2756	for (p = ents + (ctx->pos - 2); p < ents + nents; p++) {2757		if (!proc_fill_cache(file, ctx, p->name, p->len,2758				proc_pident_instantiate, task, p))2759			break;2760		ctx->pos++;2761	}2762out:2763	put_task_struct(task);2764	return 0;2765}2766 2767#ifdef CONFIG_SECURITY2768static int proc_pid_attr_open(struct inode *inode, struct file *file)2769{2770	file->private_data = NULL;2771	__mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);2772	return 0;2773}2774 2775static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,2776				  size_t count, loff_t *ppos)2777{2778	struct inode * inode = file_inode(file);2779	char *p = NULL;2780	ssize_t length;2781	struct task_struct *task = get_proc_task(inode);2782 2783	if (!task)2784		return -ESRCH;2785 2786	length = security_getprocattr(task, PROC_I(inode)->op.lsmid,2787				      file->f_path.dentry->d_name.name,2788				      &p);2789	put_task_struct(task);2790	if (length > 0)2791		length = simple_read_from_buffer(buf, count, ppos, p, length);2792	kfree(p);2793	return length;2794}2795 2796static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,2797				   size_t count, loff_t *ppos)2798{2799	struct inode * inode = file_inode(file);2800	struct task_struct *task;2801	void *page;2802	int rv;2803 2804	/* A task may only write when it was the opener. */2805	if (file->private_data != current->mm)2806		return -EPERM;2807 2808	rcu_read_lock();2809	task = pid_task(proc_pid(inode), PIDTYPE_PID);2810	if (!task) {2811		rcu_read_unlock();2812		return -ESRCH;2813	}2814	/* A task may only write its own attributes. */2815	if (current != task) {2816		rcu_read_unlock();2817		return -EACCES;2818	}2819	/* Prevent changes to overridden credentials. */2820	if (current_cred() != current_real_cred()) {2821		rcu_read_unlock();2822		return -EBUSY;2823	}2824	rcu_read_unlock();2825 2826	if (count > PAGE_SIZE)2827		count = PAGE_SIZE;2828 2829	/* No partial writes. */2830	if (*ppos != 0)2831		return -EINVAL;2832 2833	page = memdup_user(buf, count);2834	if (IS_ERR(page)) {2835		rv = PTR_ERR(page);2836		goto out;2837	}2838 2839	/* Guard against adverse ptrace interaction */2840	rv = mutex_lock_interruptible(&current->signal->cred_guard_mutex);2841	if (rv < 0)2842		goto out_free;2843 2844	rv = security_setprocattr(PROC_I(inode)->op.lsmid,2845				  file->f_path.dentry->d_name.name, page,2846				  count);2847	mutex_unlock(&current->signal->cred_guard_mutex);2848out_free:2849	kfree(page);2850out:2851	return rv;2852}2853 2854static const struct file_operations proc_pid_attr_operations = {2855	.open		= proc_pid_attr_open,2856	.read		= proc_pid_attr_read,2857	.write		= proc_pid_attr_write,2858	.llseek		= generic_file_llseek,2859	.release	= mem_release,2860};2861 2862#define LSM_DIR_OPS(LSM) \2863static int proc_##LSM##_attr_dir_iterate(struct file *filp, \2864			     struct dir_context *ctx) \2865{ \2866	return proc_pident_readdir(filp, ctx, \2867				   LSM##_attr_dir_stuff, \2868				   ARRAY_SIZE(LSM##_attr_dir_stuff)); \2869} \2870\2871static const struct file_operations proc_##LSM##_attr_dir_ops = { \2872	.read		= generic_read_dir, \2873	.iterate_shared	= proc_##LSM##_attr_dir_iterate, \2874	.llseek		= default_llseek, \2875}; \2876\2877static struct dentry *proc_##LSM##_attr_dir_lookup(struct inode *dir, \2878				struct dentry *dentry, unsigned int flags) \2879{ \2880	return proc_pident_lookup(dir, dentry, \2881				  LSM##_attr_dir_stuff, \2882				  LSM##_attr_dir_stuff + ARRAY_SIZE(LSM##_attr_dir_stuff)); \2883} \2884\2885static const struct inode_operations proc_##LSM##_attr_dir_inode_ops = { \2886	.lookup		= proc_##LSM##_attr_dir_lookup, \2887	.getattr	= pid_getattr, \2888	.setattr	= proc_setattr, \2889}2890 2891#ifdef CONFIG_SECURITY_SMACK2892static const struct pid_entry smack_attr_dir_stuff[] = {2893	ATTR(LSM_ID_SMACK, "current",	0666),2894};2895LSM_DIR_OPS(smack);2896#endif2897 2898#ifdef CONFIG_SECURITY_APPARMOR2899static const struct pid_entry apparmor_attr_dir_stuff[] = {2900	ATTR(LSM_ID_APPARMOR, "current",	0666),2901	ATTR(LSM_ID_APPARMOR, "prev",		0444),2902	ATTR(LSM_ID_APPARMOR, "exec",		0666),2903};2904LSM_DIR_OPS(apparmor);2905#endif2906 2907static const struct pid_entry attr_dir_stuff[] = {2908	ATTR(LSM_ID_UNDEF, "current",	0666),2909	ATTR(LSM_ID_UNDEF, "prev",		0444),2910	ATTR(LSM_ID_UNDEF, "exec",		0666),2911	ATTR(LSM_ID_UNDEF, "fscreate",	0666),2912	ATTR(LSM_ID_UNDEF, "keycreate",	0666),2913	ATTR(LSM_ID_UNDEF, "sockcreate",	0666),2914#ifdef CONFIG_SECURITY_SMACK2915	DIR("smack",			0555,2916	    proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops),2917#endif2918#ifdef CONFIG_SECURITY_APPARMOR2919	DIR("apparmor",			0555,2920	    proc_apparmor_attr_dir_inode_ops, proc_apparmor_attr_dir_ops),2921#endif2922};2923 2924static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx)2925{2926	return proc_pident_readdir(file, ctx, 2927				   attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));2928}2929 2930static const struct file_operations proc_attr_dir_operations = {2931	.read		= generic_read_dir,2932	.iterate_shared	= proc_attr_dir_readdir,2933	.llseek		= generic_file_llseek,2934};2935 2936static struct dentry *proc_attr_dir_lookup(struct inode *dir,2937				struct dentry *dentry, unsigned int flags)2938{2939	return proc_pident_lookup(dir, dentry,2940				  attr_dir_stuff,2941				  attr_dir_stuff + ARRAY_SIZE(attr_dir_stuff));2942}2943 2944static const struct inode_operations proc_attr_dir_inode_operations = {2945	.lookup		= proc_attr_dir_lookup,2946	.getattr	= pid_getattr,2947	.setattr	= proc_setattr,2948};2949 2950#endif2951 2952#ifdef CONFIG_ELF_CORE2953static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,2954					 size_t count, loff_t *ppos)2955{2956	struct task_struct *task = get_proc_task(file_inode(file));2957	struct mm_struct *mm;2958	char buffer[PROC_NUMBUF];2959	size_t len;2960	int ret;2961 2962	if (!task)2963		return -ESRCH;2964 2965	ret = 0;2966	mm = get_task_mm(task);2967	if (mm) {2968		len = snprintf(buffer, sizeof(buffer), "%08lx\n",2969			       ((mm->flags & MMF_DUMP_FILTER_MASK) >>2970				MMF_DUMP_FILTER_SHIFT));2971		mmput(mm);2972		ret = simple_read_from_buffer(buf, count, ppos, buffer, len);2973	}2974 2975	put_task_struct(task);2976 2977	return ret;2978}2979 2980static HWJS_SUSPENDS ssize_t proc_coredump_filter_write(struct file *file,2981					  const char __user *buf,2982					  size_t count,2983					  loff_t *ppos)2984{2985	struct task_struct *task;2986	struct mm_struct *mm;2987	unsigned int val;2988	int ret;2989	int i;2990	unsigned long mask;2991 2992	ret = kstrtouint_from_user(buf, count, 0, &val);2993	if (ret < 0)2994		return ret;2995 2996	ret = -ESRCH;2997	task = get_proc_task(file_inode(file));2998	if (!task)2999		goto out_no_task;3000 3001	mm = get_task_mm(task);3002	if (!mm)3003		goto out_no_mm;3004	ret = 0;3005 3006	for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {3007		if (val & mask)3008			set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);3009		else3010			clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);3011	}3012 3013	mmput(mm);3014 out_no_mm:3015	put_task_struct(task);3016 out_no_task:3017	if (ret < 0)3018		return ret;3019	return count;3020}3021 3022static const struct file_operations proc_coredump_filter_operations = {3023	.read		= proc_coredump_filter_read,3024	.write		= proc_coredump_filter_write,3025	.llseek		= generic_file_llseek,3026};3027#endif3028 3029#ifdef CONFIG_TASK_IO_ACCOUNTING3030static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)3031{3032	struct task_io_accounting acct;3033	int result;3034 3035	result = down_read_killable(&task->signal->exec_update_lock);3036	if (result)3037		return result;3038 3039	if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {3040		result = -EACCES;3041		goto out_unlock;3042	}3043 3044	if (whole) {3045		struct signal_struct *sig = task->signal;3046		struct task_struct *t;3047		unsigned int seq = 1;3048		unsigned long flags;3049 3050		rcu_read_lock();3051		do {3052			seq++; /* 2 on the 1st/lockless path, otherwise odd */3053			flags = read_seqbegin_or_lock_irqsave(&sig->stats_lock, &seq);3054 3055			acct = sig->ioac;3056			__for_each_thread(sig, t)3057				task_io_accounting_add(&acct, &t->ioac);3058 3059		} while (need_seqretry(&sig->stats_lock, seq));3060		done_seqretry_irqrestore(&sig->stats_lock, seq, flags);3061		rcu_read_unlock();3062	} else {3063		acct = task->ioac;3064	}3065 3066	seq_printf(m,3067		   "rchar: %llu\n"3068		   "wchar: %llu\n"3069		   "syscr: %llu\n"3070		   "syscw: %llu\n"3071		   "read_bytes: %llu\n"3072		   "write_bytes: %llu\n"3073		   "cancelled_write_bytes: %llu\n",3074		   (unsigned long long)acct.rchar,3075		   (unsigned long long)acct.wchar,3076		   (unsigned long long)acct.syscr,3077		   (unsigned long long)acct.syscw,3078		   (unsigned long long)acct.read_bytes,3079		   (unsigned long long)acct.write_bytes,3080		   (unsigned long long)acct.cancelled_write_bytes);3081	result = 0;3082 3083out_unlock:3084	up_read(&task->signal->exec_update_lock);3085	return result;3086}3087 3088static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns,3089				  struct pid *pid, struct task_struct *task)3090{3091	return do_io_accounting(task, m, 0);3092}3093 3094static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns,3095				   struct pid *pid, struct task_struct *task)3096{3097	return do_io_accounting(task, m, 1);3098}3099#endif /* CONFIG_TASK_IO_ACCOUNTING */3100 3101#ifdef CONFIG_USER_NS3102static int proc_id_map_open(struct inode *inode, struct file *file,3103	const struct seq_operations *seq_ops)3104{3105	struct user_namespace *ns = NULL;3106	struct task_struct *task;3107	struct seq_file *seq;3108	int ret = -EINVAL;3109 3110	task = get_proc_task(inode);3111	if (task) {3112		rcu_read_lock();3113		ns = get_user_ns(task_cred_xxx(task, user_ns));3114		rcu_read_unlock();3115		put_task_struct(task);3116	}3117	if (!ns)3118		goto err;3119 3120	ret = seq_open(file, seq_ops);3121	if (ret)3122		goto err_put_ns;3123 3124	seq = file->private_data;3125	seq->private = ns;3126 3127	return 0;3128err_put_ns:3129	put_user_ns(ns);3130err:3131	return ret;3132}3133 3134static int proc_id_map_release(struct inode *inode, struct file *file)3135{3136	struct seq_file *seq = file->private_data;3137	struct user_namespace *ns = seq->private;3138	put_user_ns(ns);3139	return seq_release(inode, file);3140}3141 3142static int proc_uid_map_open(struct inode *inode, struct file *file)3143{3144	return proc_id_map_open(inode, file, &proc_uid_seq_operations);3145}3146 3147static int proc_gid_map_open(struct inode *inode, struct file *file)3148{3149	return proc_id_map_open(inode, file, &proc_gid_seq_operations);3150}3151 3152static int proc_projid_map_open(struct inode *inode, struct file *file)3153{3154	return proc_id_map_open(inode, file, &proc_projid_seq_operations);3155}3156 3157static const struct file_operations proc_uid_map_operations = {3158	.open		= proc_uid_map_open,3159	.write		= proc_uid_map_write,3160	.read		= seq_read,3161	.llseek		= seq_lseek,3162	.release	= proc_id_map_release,3163};3164 3165static const struct file_operations proc_gid_map_operations = {3166	.open		= proc_gid_map_open,3167	.write		= proc_gid_map_write,3168	.read		= seq_read,3169	.llseek		= seq_lseek,3170	.release	= proc_id_map_release,3171};3172 3173static const struct file_operations proc_projid_map_operations = {3174	.open		= proc_projid_map_open,3175	.write		= proc_projid_map_write,3176	.read		= seq_read,3177	.llseek		= seq_lseek,3178	.release	= proc_id_map_release,3179};3180 3181static int proc_setgroups_open(struct inode *inode, struct file *file)3182{3183	struct user_namespace *ns = NULL;3184	struct task_struct *task;3185	int ret;3186 3187	ret = -ESRCH;3188	task = get_proc_task(inode);3189	if (task) {3190		rcu_read_lock();3191		ns = get_user_ns(task_cred_xxx(task, user_ns));3192		rcu_read_unlock();3193		put_task_struct(task);3194	}3195	if (!ns)3196		goto err;3197 3198	if (file->f_mode & FMODE_WRITE) {3199		ret = -EACCES;3200		if (!ns_capable(ns, CAP_SYS_ADMIN))3201			goto err_put_ns;3202	}3203 3204	ret = single_open(file, &proc_setgroups_show, ns);3205	if (ret)3206		goto err_put_ns;3207 3208	return 0;3209err_put_ns:3210	put_user_ns(ns);3211err:3212	return ret;3213}3214 3215static int proc_setgroups_release(struct inode *inode, struct file *file)3216{3217	struct seq_file *seq = file->private_data;3218	struct user_namespace *ns = seq->private;3219	int ret = single_release(inode, file);3220	put_user_ns(ns);3221	return ret;3222}3223 3224static const struct file_operations proc_setgroups_operations = {3225	.open		= proc_setgroups_open,3226	.write		= proc_setgroups_write,3227	.read		= seq_read,3228	.llseek		= seq_lseek,3229	.release	= proc_setgroups_release,3230};3231#endif /* CONFIG_USER_NS */3232 3233static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,3234				struct pid *pid, struct task_struct *task)3235{3236	int err = lock_trace(task);3237	if (!err) {3238		seq_printf(m, "%08x\n", task->personality);3239		unlock_trace(task);3240	}3241	return err;3242}3243 3244#ifdef CONFIG_LIVEPATCH3245static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns,3246				struct pid *pid, struct task_struct *task)3247{3248	seq_printf(m, "%d\n", task->patch_state);3249	return 0;3250}3251#endif /* CONFIG_LIVEPATCH */3252 3253#ifdef CONFIG_KSM3254static int proc_pid_ksm_merging_pages(struct seq_file *m, struct pid_namespace *ns,3255				struct pid *pid, struct task_struct *task)3256{3257	struct mm_struct *mm;3258 3259	mm = get_task_mm(task);3260	if (mm) {3261		seq_printf(m, "%lu\n", mm->ksm_merging_pages);3262		mmput(mm);3263	}3264 3265	return 0;3266}3267static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns,3268				struct pid *pid, struct task_struct *task)3269{3270	struct mm_struct *mm;3271 3272	mm = get_task_mm(task);3273	if (mm) {3274		seq_printf(m, "ksm_rmap_items %lu\n", mm->ksm_rmap_items);3275		seq_printf(m, "ksm_zero_pages %ld\n", mm_ksm_zero_pages(mm));3276		seq_printf(m, "ksm_merging_pages %lu\n", mm->ksm_merging_pages);3277		seq_printf(m, "ksm_process_profit %ld\n", ksm_process_profit(mm));3278		mmput(mm);3279	}3280 3281	return 0;3282}3283#endif /* CONFIG_KSM */3284 3285#ifdef CONFIG_STACKLEAK_METRICS3286static int proc_stack_depth(struct seq_file *m, struct pid_namespace *ns,3287				struct pid *pid, struct task_struct *task)3288{3289	unsigned long prev_depth = THREAD_SIZE -3290				(task->prev_lowest_stack & (THREAD_SIZE - 1));3291	unsigned long depth = THREAD_SIZE -3292				(task->lowest_stack & (THREAD_SIZE - 1));3293 3294	seq_printf(m, "previous stack depth: %lu\nstack depth: %lu\n",3295							prev_depth, depth);3296	return 0;3297}3298#endif /* CONFIG_STACKLEAK_METRICS */3299 3300/*3301 * Thread groups3302 */3303static const struct file_operations proc_task_operations;3304static const struct inode_operations proc_task_inode_operations;3305 3306static const struct pid_entry tgid_base_stuff[] = {3307	DIR("task",       S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),3308	DIR("fd",         S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),3309	DIR("map_files",  S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),3310	DIR("fdinfo",     S_IRUGO|S_IXUGO, proc_fdinfo_inode_operations, proc_fdinfo_operations),3311	DIR("ns",	  S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),3312#ifdef CONFIG_NET3313	DIR("net",        S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),3314#endif3315	REG("environ",    S_IRUSR, proc_environ_operations),3316	REG("auxv",       S_IRUSR, proc_auxv_operations),3317	ONE("status",     S_IRUGO, proc_pid_status),3318	ONE("personality", S_IRUSR, proc_pid_personality),3319	ONE("limits",	  S_IRUGO, proc_pid_limits),3320#ifdef CONFIG_SCHED_DEBUG3321	REG("sched",      S_IRUGO|S_IWUSR, proc_pid_sched_operations),3322#endif3323#ifdef CONFIG_SCHED_AUTOGROUP3324	REG("autogroup",  S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),3325#endif3326#ifdef CONFIG_TIME_NS3327	REG("timens_offsets",  S_IRUGO|S_IWUSR, proc_timens_offsets_operations),3328#endif3329	REG("comm",      S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),3330#ifdef CONFIG_HAVE_ARCH_TRACEHOOK3331	ONE("syscall",    S_IRUSR, proc_pid_syscall),3332#endif3333	REG("cmdline",    S_IRUGO, proc_pid_cmdline_ops),3334	ONE("stat",       S_IRUGO, proc_tgid_stat),3335	ONE("statm",      S_IRUGO, proc_pid_statm),3336	REG("maps",       S_IRUGO, proc_pid_maps_operations),3337#ifdef CONFIG_NUMA3338	REG("numa_maps",  S_IRUGO, proc_pid_numa_maps_operations),3339#endif3340	REG("mem",        S_IRUSR|S_IWUSR, proc_mem_operations),3341	LNK("cwd",        proc_cwd_link),3342	LNK("root",       proc_root_link),3343	LNK("exe",        proc_exe_link),3344	REG("mounts",     S_IRUGO, proc_mounts_operations),3345	REG("mountinfo",  S_IRUGO, proc_mountinfo_operations),3346	REG("mountstats", S_IRUSR, proc_mountstats_operations),3347#ifdef CONFIG_PROC_PAGE_MONITOR3348	REG("clear_refs", S_IWUSR, proc_clear_refs_operations),3349	REG("smaps",      S_IRUGO, proc_pid_smaps_operations),3350	REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),3351	REG("pagemap",    S_IRUSR, proc_pagemap_operations),3352#endif3353#ifdef CONFIG_SECURITY3354	DIR("attr",       S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),3355#endif3356#ifdef CONFIG_KALLSYMS3357	ONE("wchan",      S_IRUGO, proc_pid_wchan),3358#endif3359#ifdef CONFIG_STACKTRACE3360	ONE("stack",      S_IRUSR, proc_pid_stack),3361#endif3362#ifdef CONFIG_SCHED_INFO3363	ONE("schedstat",  S_IRUGO, proc_pid_schedstat),3364#endif3365#ifdef CONFIG_LATENCYTOP3366	REG("latency",  S_IRUGO, proc_lstats_operations),3367#endif3368#ifdef CONFIG_PROC_PID_CPUSET3369	ONE("cpuset",     S_IRUGO, proc_cpuset_show),3370#endif3371#ifdef CONFIG_CGROUPS3372	ONE("cgroup",  S_IRUGO, proc_cgroup_show),3373#endif3374#ifdef CONFIG_PROC_CPU_RESCTRL3375	ONE("cpu_resctrl_groups", S_IRUGO, proc_resctrl_show),3376#endif3377	ONE("oom_score",  S_IRUGO, proc_oom_score),3378	REG("oom_adj",    S_IRUGO|S_IWUSR, proc_oom_adj_operations),3379	REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),3380#ifdef CONFIG_AUDIT3381	REG("loginuid",   S_IWUSR|S_IRUGO, proc_loginuid_operations),3382	REG("sessionid",  S_IRUGO, proc_sessionid_operations),3383#endif3384#ifdef CONFIG_FAULT_INJECTION3385	REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),3386	REG("fail-nth", 0644, proc_fail_nth_operations),3387#endif3388#ifdef CONFIG_ELF_CORE3389	REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),3390#endif3391#ifdef CONFIG_TASK_IO_ACCOUNTING3392	ONE("io",	S_IRUSR, proc_tgid_io_accounting),3393#endif3394#ifdef CONFIG_USER_NS3395	REG("uid_map",    S_IRUGO|S_IWUSR, proc_uid_map_operations),3396	REG("gid_map",    S_IRUGO|S_IWUSR, proc_gid_map_operations),3397	REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),3398	REG("setgroups",  S_IRUGO|S_IWUSR, proc_setgroups_operations),3399#endif3400#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)3401	REG("timers",	  S_IRUGO, proc_timers_operations),3402#endif3403	REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations),3404#ifdef CONFIG_LIVEPATCH3405	ONE("patch_state",  S_IRUSR, proc_pid_patch_state),3406#endif3407#ifdef CONFIG_STACKLEAK_METRICS3408	ONE("stack_depth", S_IRUGO, proc_stack_depth),3409#endif3410#ifdef CONFIG_PROC_PID_ARCH_STATUS3411	ONE("arch_status", S_IRUGO, proc_pid_arch_status),3412#endif3413#ifdef CONFIG_SECCOMP_CACHE_DEBUG3414	ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache),3415#endif3416#ifdef CONFIG_KSM3417	ONE("ksm_merging_pages",  S_IRUSR, proc_pid_ksm_merging_pages),3418	ONE("ksm_stat",  S_IRUSR, proc_pid_ksm_stat),3419#endif3420};3421 3422static HWJS_SUSPENDS int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx)3423{3424	return proc_pident_readdir(file, ctx,3425				   tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));3426}3427 3428static const struct file_operations proc_tgid_base_operations = {3429	.read		= generic_read_dir,3430	.iterate_shared	= proc_tgid_base_readdir,3431	.llseek		= generic_file_llseek,3432};3433 3434struct pid *tgid_pidfd_to_pid(const struct file *file)3435{3436	if (file->f_op != &proc_tgid_base_operations)3437		return ERR_PTR(-EBADF);3438 3439	return proc_pid(file_inode(file));3440}3441 3442static HWJS_SUSPENDS struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)3443{3444	return proc_pident_lookup(dir, dentry,3445				  tgid_base_stuff,3446				  tgid_base_stuff + ARRAY_SIZE(tgid_base_stuff));3447}3448 3449static const struct inode_operations proc_tgid_base_inode_operations = {3450	.lookup		= proc_tgid_base_lookup,3451	.getattr	= pid_getattr,3452	.setattr	= proc_setattr,3453	.permission	= proc_pid_permission,3454};3455 3456/**3457 * proc_flush_pid -  Remove dcache entries for @pid from the /proc dcache.3458 * @pid: pid that should be flushed.3459 *3460 * This function walks a list of inodes (that belong to any proc3461 * filesystem) that are attached to the pid and flushes them from3462 * the dentry cache.3463 *3464 * It is safe and reasonable to cache /proc entries for a task until3465 * that task exits.  After that they just clog up the dcache with3466 * useless entries, possibly causing useful dcache entries to be3467 * flushed instead.  This routine is provided to flush those useless3468 * dcache entries when a process is reaped.3469 *3470 * NOTE: This routine is just an optimization so it does not guarantee3471 *       that no dcache entries will exist after a process is reaped3472 *       it just makes it very unlikely that any will persist.3473 */3474 3475void proc_flush_pid(struct pid *pid)3476{3477	proc_invalidate_siblings_dcache(&pid->inodes, &pid->lock);3478}3479 3480static HWJS_SUSPENDS struct dentry *proc_pid_instantiate(struct dentry * dentry,3481				   struct task_struct *task, const void *ptr)3482{3483	struct inode *inode;3484 3485	inode = proc_pid_make_base_inode(dentry->d_sb, task,3486					 S_IFDIR | S_IRUGO | S_IXUGO);3487	if (!inode)3488		return ERR_PTR(-ENOENT);3489 3490	inode->i_op = &proc_tgid_base_inode_operations;3491	inode->i_fop = &proc_tgid_base_operations;3492	inode->i_flags|=S_IMMUTABLE;3493 3494	set_nlink(inode, nlink_tgid);3495	pid_update_inode(task, inode);3496 3497	d_set_d_op(dentry, &pid_dentry_operations);3498	return d_splice_alias(inode, dentry);3499}3500 3501struct dentry *proc_pid_lookup(struct dentry *dentry, unsigned int flags)3502{3503	struct task_struct *task;3504	unsigned tgid;3505	struct proc_fs_info *fs_info;3506	struct pid_namespace *ns;3507	struct dentry *result = ERR_PTR(-ENOENT);3508 3509	tgid = name_to_int(&dentry->d_name);3510	if (tgid == ~0U)3511		goto out;3512 3513	fs_info = proc_sb_info(dentry->d_sb);3514	ns = fs_info->pid_ns;3515	rcu_read_lock();3516	task = find_task_by_pid_ns(tgid, ns);3517	if (task)3518		get_task_struct(task);3519	rcu_read_unlock();3520	if (!task)3521		goto out;3522 3523	/* Limit procfs to only ptraceable tasks */3524	if (fs_info->hide_pid == HIDEPID_NOT_PTRACEABLE) {3525		if (!has_pid_permissions(fs_info, task, HIDEPID_NO_ACCESS))3526			goto out_put_task;3527	}3528 3529	result = proc_pid_instantiate(dentry, task, NULL);3530out_put_task:3531	put_task_struct(task);3532out:3533	return result;3534}3535 3536/*3537 * Find the first task with tgid >= tgid3538 *3539 */3540struct tgid_iter {3541	unsigned int tgid;3542	struct task_struct *task;3543};3544static HWJS_SUSPENDS struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)3545{3546	struct pid *pid;3547 3548	if (iter.task)3549		put_task_struct(iter.task);3550	rcu_read_lock();3551retry:3552	iter.task = NULL;3553	pid = find_ge_pid(iter.tgid, ns);3554	if (pid) {3555		iter.tgid = pid_nr_ns(pid, ns);3556		iter.task = pid_task(pid, PIDTYPE_TGID);3557		if (!iter.task) {3558			iter.tgid += 1;3559			goto retry;3560		}3561		get_task_struct(iter.task);3562	}3563	rcu_read_unlock();3564	return iter;3565}3566 3567#define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2)3568 3569/* for the /proc/ directory itself, after non-process stuff has been done */3570int proc_pid_readdir(struct file *file, struct dir_context *ctx)3571{3572	struct tgid_iter iter;3573	struct proc_fs_info *fs_info = proc_sb_info(file_inode(file)->i_sb);3574	struct pid_namespace *ns = proc_pid_ns(file_inode(file)->i_sb);3575	loff_t pos = ctx->pos;3576 3577	if (pos >= PID_MAX_LIMIT + TGID_OFFSET)3578		return 0;3579 3580	if (pos == TGID_OFFSET - 2) {3581		struct inode *inode = d_inode(fs_info->proc_self);3582		if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK))3583			return 0;3584		ctx->pos = pos = pos + 1;3585	}3586	if (pos == TGID_OFFSET - 1) {3587		struct inode *inode = d_inode(fs_info->proc_thread_self);3588		if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK))3589			return 0;3590		ctx->pos = pos = pos + 1;3591	}3592	iter.tgid = pos - TGID_OFFSET;3593	iter.task = NULL;3594	for (iter = next_tgid(ns, iter);3595	     iter.task;3596	     iter.tgid += 1, iter = next_tgid(ns, iter)) {3597		char name[10 + 1];3598		unsigned int len;3599 3600		cond_resched();3601		if (!has_pid_permissions(fs_info, iter.task, HIDEPID_INVISIBLE))3602			continue;3603 3604		len = snprintf(name, sizeof(name), "%u", iter.tgid);3605		ctx->pos = iter.tgid + TGID_OFFSET;3606		if (!proc_fill_cache(file, ctx, name, len,3607				     proc_pid_instantiate, iter.task, NULL)) {3608			put_task_struct(iter.task);3609			return 0;3610		}3611	}3612	ctx->pos = PID_MAX_LIMIT + TGID_OFFSET;3613	return 0;3614}3615 3616/*3617 * proc_tid_comm_permission is a special permission function exclusively3618 * used for the node /proc/<pid>/task/<tid>/comm.3619 * It bypasses generic permission checks in the case where a task of the same3620 * task group attempts to access the node.3621 * The rationale behind this is that glibc and bionic access this node for3622 * cross thread naming (pthread_set/getname_np(!self)). However, if3623 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0,3624 * which locks out the cross thread naming implementation.3625 * This function makes sure that the node is always accessible for members of3626 * same thread group.3627 */3628static HWJS_SUSPENDS int proc_tid_comm_permission(struct mnt_idmap *idmap,3629				    struct inode *inode, int mask)3630{3631	bool is_same_tgroup;3632	struct task_struct *task;3633 3634	task = get_proc_task(inode);3635	if (!task)3636		return -ESRCH;3637	is_same_tgroup = same_thread_group(current, task);3638	put_task_struct(task);3639 3640	if (likely(is_same_tgroup && !(mask & MAY_EXEC))) {3641		/* This file (/proc/<pid>/task/<tid>/comm) can always be3642		 * read or written by the members of the corresponding3643		 * thread group.3644		 */3645		return 0;3646	}3647 3648	return generic_permission(&nop_mnt_idmap, inode, mask);3649}3650 3651static const struct inode_operations proc_tid_comm_inode_operations = {3652		.setattr	= proc_setattr,3653		.permission	= proc_tid_comm_permission,3654};3655 3656/*3657 * Tasks3658 */3659static const struct pid_entry tid_base_stuff[] = {3660	DIR("fd",        S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),3661	DIR("fdinfo",    S_IRUGO|S_IXUGO, proc_fdinfo_inode_operations, proc_fdinfo_operations),3662	DIR("ns",	 S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),3663#ifdef CONFIG_NET3664	DIR("net",        S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),3665#endif3666	REG("environ",   S_IRUSR, proc_environ_operations),3667	REG("auxv",      S_IRUSR, proc_auxv_operations),3668	ONE("status",    S_IRUGO, proc_pid_status),3669	ONE("personality", S_IRUSR, proc_pid_personality),3670	ONE("limits",	 S_IRUGO, proc_pid_limits),3671#ifdef CONFIG_SCHED_DEBUG3672	REG("sched",     S_IRUGO|S_IWUSR, proc_pid_sched_operations),3673#endif3674	NOD("comm",      S_IFREG|S_IRUGO|S_IWUSR,3675			 &proc_tid_comm_inode_operations,3676			 &proc_pid_set_comm_operations, {}),3677#ifdef CONFIG_HAVE_ARCH_TRACEHOOK3678	ONE("syscall",   S_IRUSR, proc_pid_syscall),3679#endif3680	REG("cmdline",   S_IRUGO, proc_pid_cmdline_ops),3681	ONE("stat",      S_IRUGO, proc_tid_stat),3682	ONE("statm",     S_IRUGO, proc_pid_statm),3683	REG("maps",      S_IRUGO, proc_pid_maps_operations),3684#ifdef CONFIG_PROC_CHILDREN3685	REG("children",  S_IRUGO, proc_tid_children_operations),3686#endif3687#ifdef CONFIG_NUMA3688	REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),3689#endif3690	REG("mem",       S_IRUSR|S_IWUSR, proc_mem_operations),3691	LNK("cwd",       proc_cwd_link),3692	LNK("root",      proc_root_link),3693	LNK("exe",       proc_exe_link),3694	REG("mounts",    S_IRUGO, proc_mounts_operations),3695	REG("mountinfo",  S_IRUGO, proc_mountinfo_operations),3696#ifdef CONFIG_PROC_PAGE_MONITOR3697	REG("clear_refs", S_IWUSR, proc_clear_refs_operations),3698	REG("smaps",     S_IRUGO, proc_pid_smaps_operations),3699	REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),3700	REG("pagemap",    S_IRUSR, proc_pagemap_operations),3701#endif3702#ifdef CONFIG_SECURITY3703	DIR("attr",      S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),3704#endif3705#ifdef CONFIG_KALLSYMS3706	ONE("wchan",     S_IRUGO, proc_pid_wchan),3707#endif3708#ifdef CONFIG_STACKTRACE3709	ONE("stack",      S_IRUSR, proc_pid_stack),3710#endif3711#ifdef CONFIG_SCHED_INFO3712	ONE("schedstat", S_IRUGO, proc_pid_schedstat),3713#endif3714#ifdef CONFIG_LATENCYTOP3715	REG("latency",  S_IRUGO, proc_lstats_operations),3716#endif3717#ifdef CONFIG_PROC_PID_CPUSET3718	ONE("cpuset",    S_IRUGO, proc_cpuset_show),3719#endif3720#ifdef CONFIG_CGROUPS3721	ONE("cgroup",  S_IRUGO, proc_cgroup_show),3722#endif3723#ifdef CONFIG_PROC_CPU_RESCTRL3724	ONE("cpu_resctrl_groups", S_IRUGO, proc_resctrl_show),3725#endif3726	ONE("oom_score", S_IRUGO, proc_oom_score),3727	REG("oom_adj",   S_IRUGO|S_IWUSR, proc_oom_adj_operations),3728	REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),3729#ifdef CONFIG_AUDIT3730	REG("loginuid",  S_IWUSR|S_IRUGO, proc_loginuid_operations),3731	REG("sessionid",  S_IRUGO, proc_sessionid_operations),3732#endif3733#ifdef CONFIG_FAULT_INJECTION3734	REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),3735	REG("fail-nth", 0644, proc_fail_nth_operations),3736#endif3737#ifdef CONFIG_TASK_IO_ACCOUNTING3738	ONE("io",	S_IRUSR, proc_tid_io_accounting),3739#endif3740#ifdef CONFIG_USER_NS3741	REG("uid_map",    S_IRUGO|S_IWUSR, proc_uid_map_operations),3742	REG("gid_map",    S_IRUGO|S_IWUSR, proc_gid_map_operations),3743	REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),3744	REG("setgroups",  S_IRUGO|S_IWUSR, proc_setgroups_operations),3745#endif3746#ifdef CONFIG_LIVEPATCH3747	ONE("patch_state",  S_IRUSR, proc_pid_patch_state),3748#endif3749#ifdef CONFIG_PROC_PID_ARCH_STATUS3750	ONE("arch_status", S_IRUGO, proc_pid_arch_status),3751#endif3752#ifdef CONFIG_SECCOMP_CACHE_DEBUG3753	ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache),3754#endif3755#ifdef CONFIG_KSM3756	ONE("ksm_merging_pages",  S_IRUSR, proc_pid_ksm_merging_pages),3757	ONE("ksm_stat",  S_IRUSR, proc_pid_ksm_stat),3758#endif3759};3760 3761static HWJS_SUSPENDS int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)3762{3763	return proc_pident_readdir(file, ctx,3764				   tid_base_stuff, ARRAY_SIZE(tid_base_stuff));3765}3766 3767static HWJS_SUSPENDS struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)3768{3769	return proc_pident_lookup(dir, dentry,3770				  tid_base_stuff,3771				  tid_base_stuff + ARRAY_SIZE(tid_base_stuff));3772}3773 3774static const struct file_operations proc_tid_base_operations = {3775	.read		= generic_read_dir,3776	.iterate_shared	= proc_tid_base_readdir,3777	.llseek		= generic_file_llseek,3778};3779 3780static const struct inode_operations proc_tid_base_inode_operations = {3781	.lookup		= proc_tid_base_lookup,3782	.getattr	= pid_getattr,3783	.setattr	= proc_setattr,3784};3785 3786static HWJS_SUSPENDS struct dentry *proc_task_instantiate(struct dentry *dentry,3787	struct task_struct *task, const void *ptr)3788{3789	struct inode *inode;3790	inode = proc_pid_make_base_inode(dentry->d_sb, task,3791					 S_IFDIR | S_IRUGO | S_IXUGO);3792	if (!inode)3793		return ERR_PTR(-ENOENT);3794 3795	inode->i_op = &proc_tid_base_inode_operations;3796	inode->i_fop = &proc_tid_base_operations;3797	inode->i_flags |= S_IMMUTABLE;3798 3799	set_nlink(inode, nlink_tid);3800	pid_update_inode(task, inode);3801 3802	d_set_d_op(dentry, &pid_dentry_operations);3803	return d_splice_alias(inode, dentry);3804}3805 3806static HWJS_SUSPENDS struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)3807{3808	struct task_struct *task;3809	struct task_struct *leader = get_proc_task(dir);3810	unsigned tid;3811	struct proc_fs_info *fs_info;3812	struct pid_namespace *ns;3813	struct dentry *result = ERR_PTR(-ENOENT);3814 3815	if (!leader)3816		goto out_no_task;3817 3818	tid = name_to_int(&dentry->d_name);3819	if (tid == ~0U)3820		goto out;3821 3822	fs_info = proc_sb_info(dentry->d_sb);3823	ns = fs_info->pid_ns;3824	rcu_read_lock();3825	task = find_task_by_pid_ns(tid, ns);3826	if (task)3827		get_task_struct(task);3828	rcu_read_unlock();3829	if (!task)3830		goto out;3831	if (!same_thread_group(leader, task))3832		goto out_drop_task;3833 3834	result = proc_task_instantiate(dentry, task, NULL);3835out_drop_task:3836	put_task_struct(task);3837out:3838	put_task_struct(leader);3839out_no_task:3840	return result;3841}3842 3843/*3844 * Find the first tid of a thread group to return to user space.3845 *3846 * Usually this is just the thread group leader, but if the users3847 * buffer was too small or there was a seek into the middle of the3848 * directory we have more work todo.3849 *3850 * In the case of a short read we start with find_task_by_pid.3851 *3852 * In the case of a seek we start with the leader and walk nr3853 * threads past it.3854 */3855static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos,3856					struct pid_namespace *ns)3857{3858	struct task_struct *pos, *task;3859	unsigned long nr = f_pos;3860 3861	if (nr != f_pos)	/* 32bit overflow? */3862		return NULL;3863 3864	rcu_read_lock();3865	task = pid_task(pid, PIDTYPE_PID);3866	if (!task)3867		goto fail;3868 3869	/* Attempt to start with the tid of a thread */3870	if (tid && nr) {3871		pos = find_task_by_pid_ns(tid, ns);3872		if (pos && same_thread_group(pos, task))3873			goto found;3874	}3875 3876	/* If nr exceeds the number of threads there is nothing todo */3877	if (nr >= get_nr_threads(task))3878		goto fail;3879 3880	/* If we haven't found our starting place yet start3881	 * with the leader and walk nr threads forward.3882	 */3883	for_each_thread(task, pos) {3884		if (!nr--)3885			goto found;3886	}3887fail:3888	pos = NULL;3889	goto out;3890found:3891	get_task_struct(pos);3892out:3893	rcu_read_unlock();3894	return pos;3895}3896 3897/*3898 * Find the next thread in the thread list.3899 * Return NULL if there is an error or no next thread.3900 *3901 * The reference to the input task_struct is released.3902 */3903static HWJS_SUSPENDS struct task_struct *next_tid(struct task_struct *start)3904{3905	struct task_struct *pos = NULL;3906	rcu_read_lock();3907	if (pid_alive(start)) {3908		pos = __next_thread(start);3909		if (pos)3910			get_task_struct(pos);3911	}3912	rcu_read_unlock();3913	put_task_struct(start);3914	return pos;3915}3916 3917/* for the /proc/TGID/task/ directories */3918static HWJS_SUSPENDS int proc_task_readdir(struct file *file, struct dir_context *ctx)3919{3920	struct inode *inode = file_inode(file);3921	struct task_struct *task;3922	struct pid_namespace *ns;3923	int tid;3924 3925	if (proc_inode_is_dead(inode))3926		return -ENOENT;3927 3928	if (!dir_emit_dots(file, ctx))3929		return 0;3930 3931	/* We cache the tgid value that the last readdir call couldn't3932	 * return and lseek resets it to 0.3933	 */3934	ns = proc_pid_ns(inode->i_sb);3935	tid = (int)(intptr_t)file->private_data;3936	file->private_data = NULL;3937	for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);3938	     task;3939	     task = next_tid(task), ctx->pos++) {3940		char name[10 + 1];3941		unsigned int len;3942 3943		tid = task_pid_nr_ns(task, ns);3944		if (!tid)3945			continue;	/* The task has just exited. */3946		len = snprintf(name, sizeof(name), "%u", tid);3947		if (!proc_fill_cache(file, ctx, name, len,3948				proc_task_instantiate, task, NULL)) {3949			/* returning this tgid failed, save it as the first3950			 * pid for the next readir call */3951			file->private_data = (void *)(intptr_t)tid;3952			put_task_struct(task);3953			break;3954		}3955	}3956 3957	return 0;3958}3959 3960static HWJS_SUSPENDS int proc_task_getattr(struct mnt_idmap *idmap,3961			     const struct path *path, struct kstat *stat,3962			     u32 request_mask, unsigned int query_flags)3963{3964	struct inode *inode = d_inode(path->dentry);3965	struct task_struct *p = get_proc_task(inode);3966	generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);3967 3968	if (p) {3969		stat->nlink += get_nr_threads(p);3970		put_task_struct(p);3971	}3972 3973	return 0;3974}3975 3976/*3977 * proc_task_readdir() set @file->private_data to a positive integer3978 * value, so casting that to u64 is safe. generic_llseek_cookie() will3979 * set @cookie to 0, so casting to an int is safe. The WARN_ON_ONCE() is3980 * here to catch any unexpected change in behavior either in3981 * proc_task_readdir() or generic_llseek_cookie().3982 */3983static loff_t proc_dir_llseek(struct file *file, loff_t offset, int whence)3984{3985	u64 cookie = (u64)(intptr_t)file->private_data;3986	loff_t off;3987 3988	off = generic_llseek_cookie(file, offset, whence, &cookie);3989	WARN_ON_ONCE(cookie > INT_MAX);3990	file->private_data = (void *)(intptr_t)cookie; /* serialized by f_pos_lock */3991	return off;3992}3993 3994static const struct inode_operations proc_task_inode_operations = {3995	.lookup		= proc_task_lookup,3996	.getattr	= proc_task_getattr,3997	.setattr	= proc_setattr,3998	.permission	= proc_pid_permission,3999};4000 4001static const struct file_operations proc_task_operations = {4002	.read		= generic_read_dir,4003	.iterate_shared	= proc_task_readdir,4004	.llseek		= proc_dir_llseek,4005};4006 4007void __init set_proc_pid_nlink(void)4008{4009	nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff));4010	nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));4011}4012