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1// SPDX-License-Identifier: GPL-2.02/* Copyright (C) 2019 ARM Limited */3 4#include <stdio.h>5#include <stdlib.h>6#include <signal.h>7#include <string.h>8#include <unistd.h>9#include <assert.h>10#include <sys/auxv.h>11#include <linux/auxvec.h>12#include <ucontext.h>13 14#include <asm/unistd.h>15 16#include <kselftest.h>17 18#include "test_signals.h"19#include "test_signals_utils.h"20#include "testcases/testcases.h"21 22 23extern struct tdescr *current;24 25static int sig_copyctx = SIGTRAP;26 27static char const *const feats_names[FMAX_END] = {28 " SSBS ",29 " SVE ",30 " SME ",31 " FA64 ",32 " SME2 ",33};34 35#define MAX_FEATS_SZ 12836static char feats_string[MAX_FEATS_SZ];37 38static inline char *feats_to_string(unsigned long feats)39{40 size_t flen = MAX_FEATS_SZ - 1;41 42 feats_string[0] = '\0';43 44 for (int i = 0; i < FMAX_END; i++) {45 if (feats & (1UL << i)) {46 size_t tlen = strlen(feats_names[i]);47 48 assert(flen > tlen);49 flen -= tlen;50 strncat(feats_string, feats_names[i], flen);51 }52 }53 54 return feats_string;55}56 57static void unblock_signal(int signum)58{59 sigset_t sset;60 61 sigemptyset(&sset);62 sigaddset(&sset, signum);63 sigprocmask(SIG_UNBLOCK, &sset, NULL);64}65 66static void default_result(struct tdescr *td, bool force_exit)67{68 if (td->result == KSFT_SKIP) {69 fprintf(stderr, "==>> completed. SKIP.\n");70 } else if (td->pass) {71 fprintf(stderr, "==>> completed. PASS(1)\n");72 td->result = KSFT_PASS;73 } else {74 fprintf(stdout, "==>> completed. FAIL(0)\n");75 td->result = KSFT_FAIL;76 }77 78 if (force_exit)79 exit(td->result);80}81 82/*83 * The following handle_signal_* helpers are used by main default_handler84 * and are meant to return true when signal is handled successfully:85 * when false is returned instead, it means that the signal was somehow86 * unexpected in that context and it was NOT handled; default_handler will87 * take care of such unexpected situations.88 */89 90static bool handle_signal_unsupported(struct tdescr *td,91 siginfo_t *si, void *uc)92{93 if (feats_ok(td))94 return false;95 96 /* Mangling PC to avoid loops on original SIGILL */97 ((ucontext_t *)uc)->uc_mcontext.pc += 4;98 99 if (!td->initialized) {100 fprintf(stderr,101 "Got SIG_UNSUPP @test_init. Ignore.\n");102 } else {103 fprintf(stderr,104 "-- RX SIG_UNSUPP on unsupported feat...OK\n");105 td->pass = 1;106 default_result(current, 1);107 }108 109 return true;110}111 112static bool handle_signal_trigger(struct tdescr *td,113 siginfo_t *si, void *uc)114{115 td->triggered = 1;116 /* ->run was asserted NON-NULL in test_setup() already */117 td->run(td, si, uc);118 119 return true;120}121 122static bool handle_signal_ok(struct tdescr *td,123 siginfo_t *si, void *uc)124{125 /*126 * it's a bug in the test code when this assert fail:127 * if sig_trig was defined, it must have been used before getting here.128 */129 assert(!td->sig_trig || td->triggered);130 fprintf(stderr,131 "SIG_OK -- SP:0x%llX si_addr@:%p si_code:%d token@:%p offset:%ld\n",132 ((ucontext_t *)uc)->uc_mcontext.sp,133 si->si_addr, si->si_code, td->token, td->token - si->si_addr);134 /*135 * fake_sigreturn tests, which have sanity_enabled=1, set, at the very136 * last time, the token field to the SP address used to place the fake137 * sigframe: so token==0 means we never made it to the end,138 * segfaulting well-before, and the test is possibly broken.139 */140 if (!td->sanity_disabled && !td->token) {141 fprintf(stdout,142 "current->token ZEROED...test is probably broken!\n");143 abort();144 }145 /*146 * Trying to narrow down the SEGV to the ones generated by Kernel itself147 * via arm64_notify_segfault(). This is a best-effort check anyway, and148 * the si_code check may need to change if this aspect of the kernel149 * ABI changes.150 */151 if (td->sig_ok == SIGSEGV && si->si_code != SEGV_ACCERR) {152 fprintf(stdout,153 "si_code != SEGV_ACCERR...test is probably broken!\n");154 abort();155 }156 td->pass = 1;157 /*158 * Some tests can lead to SEGV loops: in such a case we want to159 * terminate immediately exiting straight away; some others are not160 * supposed to outlive the signal handler code, due to the content of161 * the fake sigframe which caused the signal itself.162 */163 default_result(current, 1);164 165 return true;166}167 168static bool handle_signal_copyctx(struct tdescr *td,169 siginfo_t *si, void *uc_in)170{171 ucontext_t *uc = uc_in;172 struct _aarch64_ctx *head;173 struct extra_context *extra, *copied_extra;174 size_t offset = 0;175 size_t to_copy;176 177 ASSERT_GOOD_CONTEXT(uc);178 179 /* Mangling PC to avoid loops on original BRK instr */180 uc->uc_mcontext.pc += 4;181 182 /*183 * Check for an preserve any extra data too with fixups.184 */185 head = (struct _aarch64_ctx *)uc->uc_mcontext.__reserved;186 head = get_header(head, EXTRA_MAGIC, td->live_sz, &offset);187 if (head) {188 extra = (struct extra_context *)head;189 190 /*191 * The extra buffer must be immediately after the192 * extra_context and a 16 byte terminator. Include it193 * in the copy, this was previously validated in194 * ASSERT_GOOD_CONTEXT().195 */196 to_copy = __builtin_offsetof(ucontext_t,197 uc_mcontext.__reserved);198 to_copy += offset + sizeof(struct extra_context) + 16;199 to_copy += extra->size;200 copied_extra = (struct extra_context *)&(td->live_uc->uc_mcontext.__reserved[offset]);201 } else {202 copied_extra = NULL;203 to_copy = sizeof(ucontext_t);204 }205 206 if (to_copy > td->live_sz) {207 fprintf(stderr,208 "Not enough space to grab context, %lu/%lu bytes\n",209 td->live_sz, to_copy);210 return false;211 }212 213 memcpy(td->live_uc, uc, to_copy);214 215 /*216 * If there was any EXTRA_CONTEXT fix up the size to be the217 * struct extra_context and the following terminator record,218 * this means that the rest of the code does not need to have219 * special handling for the record and we don't need to fix up220 * datap for the new location.221 */222 if (copied_extra)223 copied_extra->head.size = sizeof(*copied_extra) + 16;224 225 td->live_uc_valid = 1;226 fprintf(stderr,227 "%lu byte GOOD CONTEXT grabbed from sig_copyctx handler\n",228 to_copy);229 230 return true;231}232 233static void default_handler(int signum, siginfo_t *si, void *uc)234{235 if (current->sig_unsupp && signum == current->sig_unsupp &&236 handle_signal_unsupported(current, si, uc)) {237 fprintf(stderr, "Handled SIG_UNSUPP\n");238 } else if (current->sig_trig && signum == current->sig_trig &&239 handle_signal_trigger(current, si, uc)) {240 fprintf(stderr, "Handled SIG_TRIG\n");241 } else if (current->sig_ok && signum == current->sig_ok &&242 handle_signal_ok(current, si, uc)) {243 fprintf(stderr, "Handled SIG_OK\n");244 } else if (signum == sig_copyctx && current->live_uc &&245 handle_signal_copyctx(current, si, uc)) {246 fprintf(stderr, "Handled SIG_COPYCTX\n");247 } else {248 if (signum == SIGALRM && current->timeout) {249 fprintf(stderr, "-- Timeout !\n");250 } else {251 fprintf(stderr,252 "-- RX UNEXPECTED SIGNAL: %d code %d address %p\n",253 signum, si->si_code, si->si_addr);254 }255 default_result(current, 1);256 }257}258 259static int default_setup(struct tdescr *td)260{261 struct sigaction sa;262 263 sa.sa_sigaction = default_handler;264 sa.sa_flags = SA_SIGINFO | SA_RESTART;265 sa.sa_flags |= td->sa_flags;266 sigemptyset(&sa.sa_mask);267 /* uncatchable signals naturally skipped ... */268 for (int sig = 1; sig < 32; sig++)269 sigaction(sig, &sa, NULL);270 /*271 * RT Signals default disposition is Term but they cannot be272 * generated by the Kernel in response to our tests; so just catch273 * them all and report them as UNEXPECTED signals.274 */275 for (int sig = SIGRTMIN; sig <= SIGRTMAX; sig++)276 sigaction(sig, &sa, NULL);277 278 /* just in case...unblock explicitly all we need */279 if (td->sig_trig)280 unblock_signal(td->sig_trig);281 if (td->sig_ok)282 unblock_signal(td->sig_ok);283 if (td->sig_unsupp)284 unblock_signal(td->sig_unsupp);285 286 if (td->timeout) {287 unblock_signal(SIGALRM);288 alarm(td->timeout);289 }290 fprintf(stderr, "Registered handlers for all signals.\n");291 292 return 1;293}294 295static inline int default_trigger(struct tdescr *td)296{297 return !raise(td->sig_trig);298}299 300int test_init(struct tdescr *td)301{302 if (td->sig_trig == sig_copyctx) {303 fprintf(stdout,304 "Signal %d is RESERVED, cannot be used as a trigger. Aborting\n",305 sig_copyctx);306 return 0;307 }308 /* just in case */309 unblock_signal(sig_copyctx);310 311 td->minsigstksz = getauxval(AT_MINSIGSTKSZ);312 if (!td->minsigstksz)313 td->minsigstksz = MINSIGSTKSZ;314 fprintf(stderr, "Detected MINSTKSIGSZ:%d\n", td->minsigstksz);315 316 if (td->feats_required || td->feats_incompatible) {317 td->feats_supported = 0;318 /*319 * Checking for CPU required features using both the320 * auxval and the arm64 MRS Emulation to read sysregs.321 */322 if (getauxval(AT_HWCAP) & HWCAP_SSBS)323 td->feats_supported |= FEAT_SSBS;324 if (getauxval(AT_HWCAP) & HWCAP_SVE)325 td->feats_supported |= FEAT_SVE;326 if (getauxval(AT_HWCAP2) & HWCAP2_SME)327 td->feats_supported |= FEAT_SME;328 if (getauxval(AT_HWCAP2) & HWCAP2_SME_FA64)329 td->feats_supported |= FEAT_SME_FA64;330 if (getauxval(AT_HWCAP2) & HWCAP2_SME2)331 td->feats_supported |= FEAT_SME2;332 if (feats_ok(td)) {333 if (td->feats_required & td->feats_supported)334 fprintf(stderr,335 "Required Features: [%s] supported\n",336 feats_to_string(td->feats_required &337 td->feats_supported));338 if (!(td->feats_incompatible & td->feats_supported))339 fprintf(stderr,340 "Incompatible Features: [%s] absent\n",341 feats_to_string(td->feats_incompatible));342 } else {343 if ((td->feats_required & td->feats_supported) !=344 td->feats_supported)345 fprintf(stderr,346 "Required Features: [%s] NOT supported\n",347 feats_to_string(td->feats_required &348 ~td->feats_supported));349 if (td->feats_incompatible & td->feats_supported)350 fprintf(stderr,351 "Incompatible Features: [%s] supported\n",352 feats_to_string(td->feats_incompatible &353 ~td->feats_supported));354 355 356 td->result = KSFT_SKIP;357 return 0;358 }359 }360 361 /* Perform test specific additional initialization */362 if (td->init && !td->init(td)) {363 fprintf(stderr, "FAILED Testcase initialization.\n");364 return 0;365 }366 td->initialized = 1;367 fprintf(stderr, "Testcase initialized.\n");368 369 return 1;370}371 372int test_setup(struct tdescr *td)373{374 /* assert core invariants symptom of a rotten testcase */375 assert(current);376 assert(td);377 assert(td->name);378 assert(td->run);379 380 /* Default result is FAIL if test setup fails */381 td->result = KSFT_FAIL;382 if (td->setup)383 return td->setup(td);384 else385 return default_setup(td);386}387 388int test_run(struct tdescr *td)389{390 if (td->trigger)391 return td->trigger(td);392 else if (td->sig_trig)393 return default_trigger(td);394 else395 return td->run(td, NULL, NULL);396}397 398void test_result(struct tdescr *td)399{400 if (td->initialized && td->result != KSFT_SKIP && td->check_result)401 td->check_result(td);402 default_result(td, 0);403}404 405void test_cleanup(struct tdescr *td)406{407 if (td->cleanup)408 td->cleanup(td);409}410