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1// SPDX-License-Identifier: GPL-2.02/* Copyright (C) 2019 ARM Limited */3 4#include <ctype.h>5#include <string.h>6 7#include "testcases.h"8 9bool validate_extra_context(struct extra_context *extra, char **err,10 void **extra_data, size_t *extra_size)11{12 struct _aarch64_ctx *term;13 14 if (!extra || !err)15 return false;16 17 fprintf(stderr, "Validating EXTRA...\n");18 term = GET_RESV_NEXT_HEAD(&extra->head);19 if (!term || term->magic || term->size) {20 *err = "Missing terminator after EXTRA context";21 return false;22 }23 if (extra->datap & 0x0fUL)24 *err = "Extra DATAP misaligned";25 else if (extra->size & 0x0fUL)26 *err = "Extra SIZE misaligned";27 else if (extra->datap != (uint64_t)term + 0x10UL)28 *err = "Extra DATAP misplaced (not contiguous)";29 if (*err)30 return false;31 32 *extra_data = (void *)extra->datap;33 *extra_size = extra->size;34 35 return true;36}37 38bool validate_sve_context(struct sve_context *sve, char **err)39{40 /* Size will be rounded up to a multiple of 16 bytes */41 size_t regs_size42 = ((SVE_SIG_CONTEXT_SIZE(sve_vq_from_vl(sve->vl)) + 15) / 16) * 16;43 44 if (!sve || !err)45 return false;46 47 /* Either a bare sve_context or a sve_context followed by regs data */48 if ((sve->head.size != sizeof(struct sve_context)) &&49 (sve->head.size != regs_size)) {50 *err = "bad size for SVE context";51 return false;52 }53 54 if (!sve_vl_valid(sve->vl)) {55 *err = "SVE VL invalid";56 57 return false;58 }59 60 return true;61}62 63bool validate_za_context(struct za_context *za, char **err)64{65 /* Size will be rounded up to a multiple of 16 bytes */66 size_t regs_size67 = ((ZA_SIG_CONTEXT_SIZE(sve_vq_from_vl(za->vl)) + 15) / 16) * 16;68 69 if (!za || !err)70 return false;71 72 /* Either a bare za_context or a za_context followed by regs data */73 if ((za->head.size != sizeof(struct za_context)) &&74 (za->head.size != regs_size)) {75 *err = "bad size for ZA context";76 return false;77 }78 79 if (!sve_vl_valid(za->vl)) {80 *err = "SME VL in ZA context invalid";81 82 return false;83 }84 85 return true;86}87 88bool validate_zt_context(struct zt_context *zt, char **err)89{90 if (!zt || !err)91 return false;92 93 /* If the context is present there should be at least one register */94 if (zt->nregs == 0) {95 *err = "no registers";96 return false;97 }98 99 /* Size should agree with the number of registers */100 if (zt->head.size != ZT_SIG_CONTEXT_SIZE(zt->nregs)) {101 *err = "register count does not match size";102 return false;103 }104 105 return true;106}107 108bool validate_reserved(ucontext_t *uc, size_t resv_sz, char **err)109{110 bool terminated = false;111 size_t offs = 0;112 int flags = 0;113 int new_flags, i;114 struct extra_context *extra = NULL;115 struct sve_context *sve = NULL;116 struct za_context *za = NULL;117 struct zt_context *zt = NULL;118 struct _aarch64_ctx *head =119 (struct _aarch64_ctx *)uc->uc_mcontext.__reserved;120 void *extra_data = NULL;121 size_t extra_sz = 0;122 char magic[4];123 124 if (!err)125 return false;126 /* Walk till the end terminator verifying __reserved contents */127 while (head && !terminated && offs < resv_sz) {128 if ((uint64_t)head & 0x0fUL) {129 *err = "Misaligned HEAD";130 return false;131 }132 133 new_flags = 0;134 135 switch (head->magic) {136 case 0:137 if (head->size) {138 *err = "Bad size for terminator";139 } else if (extra_data) {140 /* End of main data, walking the extra data */141 head = extra_data;142 resv_sz = extra_sz;143 offs = 0;144 145 extra_data = NULL;146 extra_sz = 0;147 continue;148 } else {149 terminated = true;150 }151 break;152 case FPSIMD_MAGIC:153 if (flags & FPSIMD_CTX)154 *err = "Multiple FPSIMD_MAGIC";155 else if (head->size !=156 sizeof(struct fpsimd_context))157 *err = "Bad size for fpsimd_context";158 new_flags |= FPSIMD_CTX;159 break;160 case ESR_MAGIC:161 if (head->size != sizeof(struct esr_context))162 *err = "Bad size for esr_context";163 break;164 case POE_MAGIC:165 if (head->size != sizeof(struct poe_context))166 *err = "Bad size for poe_context";167 break;168 case TPIDR2_MAGIC:169 if (head->size != sizeof(struct tpidr2_context))170 *err = "Bad size for tpidr2_context";171 break;172 case SVE_MAGIC:173 if (flags & SVE_CTX)174 *err = "Multiple SVE_MAGIC";175 /* Size is validated in validate_sve_context() */176 sve = (struct sve_context *)head;177 new_flags |= SVE_CTX;178 break;179 case ZA_MAGIC:180 if (flags & ZA_CTX)181 *err = "Multiple ZA_MAGIC";182 /* Size is validated in validate_za_context() */183 za = (struct za_context *)head;184 new_flags |= ZA_CTX;185 break;186 case ZT_MAGIC:187 if (flags & ZT_CTX)188 *err = "Multiple ZT_MAGIC";189 /* Size is validated in validate_za_context() */190 zt = (struct zt_context *)head;191 new_flags |= ZT_CTX;192 break;193 case FPMR_MAGIC:194 if (flags & FPMR_CTX)195 *err = "Multiple FPMR_MAGIC";196 else if (head->size !=197 sizeof(struct fpmr_context))198 *err = "Bad size for fpmr_context";199 new_flags |= FPMR_CTX;200 break;201 case EXTRA_MAGIC:202 if (flags & EXTRA_CTX)203 *err = "Multiple EXTRA_MAGIC";204 else if (head->size !=205 sizeof(struct extra_context))206 *err = "Bad size for extra_context";207 new_flags |= EXTRA_CTX;208 extra = (struct extra_context *)head;209 break;210 case KSFT_BAD_MAGIC:211 /*212 * This is a BAD magic header defined213 * artificially by a testcase and surely214 * unknown to the Kernel parse_user_sigframe().215 * It MUST cause a Kernel induced SEGV216 */217 *err = "BAD MAGIC !";218 break;219 default:220 /*221 * A still unknown Magic: potentially freshly added222 * to the Kernel code and still unknown to the223 * tests. Magic numbers are supposed to be allocated224 * as somewhat meaningful ASCII strings so try to225 * print as such as well as the raw number.226 */227 memcpy(magic, &head->magic, sizeof(magic));228 for (i = 0; i < sizeof(magic); i++)229 if (!isalnum(magic[i]))230 magic[i] = '?';231 232 fprintf(stdout,233 "SKIP Unknown MAGIC: 0x%X (%c%c%c%c) - Is KSFT arm64/signal up to date ?\n",234 head->magic,235 magic[3], magic[2], magic[1], magic[0]);236 break;237 }238 239 if (*err)240 return false;241 242 offs += head->size;243 if (resv_sz < offs + sizeof(*head)) {244 *err = "HEAD Overrun";245 return false;246 }247 248 if (new_flags & EXTRA_CTX)249 if (!validate_extra_context(extra, err,250 &extra_data, &extra_sz))251 return false;252 if (new_flags & SVE_CTX)253 if (!validate_sve_context(sve, err))254 return false;255 if (new_flags & ZA_CTX)256 if (!validate_za_context(za, err))257 return false;258 if (new_flags & ZT_CTX)259 if (!validate_zt_context(zt, err))260 return false;261 262 flags |= new_flags;263 264 head = GET_RESV_NEXT_HEAD(head);265 }266 267 if (terminated && !(flags & FPSIMD_CTX)) {268 *err = "Missing FPSIMD";269 return false;270 }271 272 if (terminated && (flags & ZT_CTX) && !(flags & ZA_CTX)) {273 *err = "ZT context but no ZA context";274 return false;275 }276 277 return true;278}279 280/*281 * This function walks through the records inside the provided reserved area282 * trying to find enough space to fit @need_sz bytes: if not enough space is283 * available and an extra_context record is present, it throws away the284 * extra_context record.285 *286 * It returns a pointer to a new header where it is possible to start storing287 * our need_sz bytes.288 *289 * @shead: points to the start of reserved area290 * @need_sz: needed bytes291 * @resv_sz: reserved area size in bytes292 * @offset: if not null, this will be filled with the offset of the return293 * head pointer from @shead294 *295 * @return: pointer to a new head where to start storing need_sz bytes, or296 * NULL if space could not be made available.297 */298struct _aarch64_ctx *get_starting_head(struct _aarch64_ctx *shead,299 size_t need_sz, size_t resv_sz,300 size_t *offset)301{302 size_t offs = 0;303 struct _aarch64_ctx *head;304 305 head = get_terminator(shead, resv_sz, &offs);306 /* not found a terminator...no need to update offset if any */307 if (!head)308 return head;309 if (resv_sz - offs < need_sz) {310 fprintf(stderr, "Low on space:%zd. Discarding extra_context.\n",311 resv_sz - offs);312 head = get_header(shead, EXTRA_MAGIC, resv_sz, &offs);313 if (!head || resv_sz - offs < need_sz) {314 fprintf(stderr,315 "Failed to reclaim space on sigframe.\n");316 return NULL;317 }318 }319 320 fprintf(stderr, "Available space:%zd\n", resv_sz - offs);321 if (offset)322 *offset = offs;323 return head;324}325