Commit | Line | Data |
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09c434b8 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * linux/fs/binfmt_elf.c | |
4 | * | |
5 | * These are the functions used to load ELF format executables as used | |
6 | * on SVr4 machines. Information on the format may be found in the book | |
7 | * "UNIX SYSTEM V RELEASE 4 Programmers Guide: Ansi C and Programming Support | |
8 | * Tools". | |
9 | * | |
10 | * Copyright 1993, 1994: Eric Youngdale (ericy@cais.com). | |
11 | */ | |
12 | ||
13 | #include <linux/module.h> | |
14 | #include <linux/kernel.h> | |
15 | #include <linux/fs.h> | |
ce81bb25 | 16 | #include <linux/log2.h> |
1da177e4 LT |
17 | #include <linux/mm.h> |
18 | #include <linux/mman.h> | |
1da177e4 LT |
19 | #include <linux/errno.h> |
20 | #include <linux/signal.h> | |
21 | #include <linux/binfmts.h> | |
22 | #include <linux/string.h> | |
23 | #include <linux/file.h> | |
1da177e4 | 24 | #include <linux/slab.h> |
1da177e4 LT |
25 | #include <linux/personality.h> |
26 | #include <linux/elfcore.h> | |
27 | #include <linux/init.h> | |
28 | #include <linux/highuid.h> | |
1da177e4 LT |
29 | #include <linux/compiler.h> |
30 | #include <linux/highmem.h> | |
03911132 | 31 | #include <linux/hugetlb.h> |
1da177e4 | 32 | #include <linux/pagemap.h> |
2aa362c4 | 33 | #include <linux/vmalloc.h> |
1da177e4 | 34 | #include <linux/security.h> |
1da177e4 | 35 | #include <linux/random.h> |
f4e5cc2c | 36 | #include <linux/elf.h> |
d1fd836d | 37 | #include <linux/elf-randomize.h> |
7e80d0d0 | 38 | #include <linux/utsname.h> |
088e7af7 | 39 | #include <linux/coredump.h> |
6fac4829 | 40 | #include <linux/sched.h> |
f7ccbae4 | 41 | #include <linux/sched/coredump.h> |
68db0cf1 | 42 | #include <linux/sched/task_stack.h> |
32ef5517 | 43 | #include <linux/sched/cputime.h> |
00e19cee DM |
44 | #include <linux/sizes.h> |
45 | #include <linux/types.h> | |
5b825c3a | 46 | #include <linux/cred.h> |
5037835c | 47 | #include <linux/dax.h> |
7c0f6ba6 | 48 | #include <linux/uaccess.h> |
1da177e4 LT |
49 | #include <asm/param.h> |
50 | #include <asm/page.h> | |
51 | ||
00e19cee DM |
52 | #ifndef ELF_COMPAT |
53 | #define ELF_COMPAT 0 | |
54 | #endif | |
55 | ||
2aa362c4 DV |
56 | #ifndef user_long_t |
57 | #define user_long_t long | |
58 | #endif | |
49ae4d4b DV |
59 | #ifndef user_siginfo_t |
60 | #define user_siginfo_t siginfo_t | |
61 | #endif | |
62 | ||
4755200b NP |
63 | /* That's for binfmt_elf_fdpic to deal with */ |
64 | #ifndef elf_check_fdpic | |
65 | #define elf_check_fdpic(ex) false | |
66 | #endif | |
67 | ||
71613c3b | 68 | static int load_elf_binary(struct linux_binprm *bprm); |
1da177e4 | 69 | |
69369a70 JT |
70 | #ifdef CONFIG_USELIB |
71 | static int load_elf_library(struct file *); | |
72 | #else | |
73 | #define load_elf_library NULL | |
74 | #endif | |
75 | ||
1da177e4 LT |
76 | /* |
77 | * If we don't support core dumping, then supply a NULL so we | |
78 | * don't even try. | |
79 | */ | |
698ba7b5 | 80 | #ifdef CONFIG_ELF_CORE |
f6151dfe | 81 | static int elf_core_dump(struct coredump_params *cprm); |
1da177e4 LT |
82 | #else |
83 | #define elf_core_dump NULL | |
84 | #endif | |
85 | ||
86 | #if ELF_EXEC_PAGESIZE > PAGE_SIZE | |
f4e5cc2c | 87 | #define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE |
1da177e4 | 88 | #else |
f4e5cc2c | 89 | #define ELF_MIN_ALIGN PAGE_SIZE |
1da177e4 LT |
90 | #endif |
91 | ||
92 | #ifndef ELF_CORE_EFLAGS | |
93 | #define ELF_CORE_EFLAGS 0 | |
94 | #endif | |
95 | ||
96 | #define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1)) | |
97 | #define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1)) | |
98 | #define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1)) | |
99 | ||
100 | static struct linux_binfmt elf_format = { | |
f670d0ec MP |
101 | .module = THIS_MODULE, |
102 | .load_binary = load_elf_binary, | |
103 | .load_shlib = load_elf_library, | |
104 | .core_dump = elf_core_dump, | |
105 | .min_coredump = ELF_EXEC_PAGESIZE, | |
1da177e4 LT |
106 | }; |
107 | ||
18676ffc | 108 | #define BAD_ADDR(x) (unlikely((unsigned long)(x) >= TASK_SIZE)) |
1da177e4 | 109 | |
16e72e9b | 110 | static int set_brk(unsigned long start, unsigned long end, int prot) |
1da177e4 LT |
111 | { |
112 | start = ELF_PAGEALIGN(start); | |
113 | end = ELF_PAGEALIGN(end); | |
114 | if (end > start) { | |
16e72e9b DV |
115 | /* |
116 | * Map the last of the bss segment. | |
117 | * If the header is requesting these pages to be | |
118 | * executable, honour that (ppc32 needs this). | |
119 | */ | |
120 | int error = vm_brk_flags(start, end - start, | |
121 | prot & PROT_EXEC ? VM_EXEC : 0); | |
5d22fc25 LT |
122 | if (error) |
123 | return error; | |
1da177e4 LT |
124 | } |
125 | current->mm->start_brk = current->mm->brk = end; | |
126 | return 0; | |
127 | } | |
128 | ||
1da177e4 LT |
129 | /* We need to explicitly zero any fractional pages |
130 | after the data section (i.e. bss). This would | |
131 | contain the junk from the file that should not | |
f4e5cc2c JJ |
132 | be in memory |
133 | */ | |
1da177e4 LT |
134 | static int padzero(unsigned long elf_bss) |
135 | { | |
136 | unsigned long nbyte; | |
137 | ||
138 | nbyte = ELF_PAGEOFFSET(elf_bss); | |
139 | if (nbyte) { | |
140 | nbyte = ELF_MIN_ALIGN - nbyte; | |
141 | if (clear_user((void __user *) elf_bss, nbyte)) | |
142 | return -EFAULT; | |
143 | } | |
144 | return 0; | |
145 | } | |
146 | ||
09c6dd3c | 147 | /* Let's use some macros to make this stack manipulation a little clearer */ |
1da177e4 LT |
148 | #ifdef CONFIG_STACK_GROWSUP |
149 | #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items)) | |
150 | #define STACK_ROUND(sp, items) \ | |
151 | ((15 + (unsigned long) ((sp) + (items))) &~ 15UL) | |
f4e5cc2c JJ |
152 | #define STACK_ALLOC(sp, len) ({ \ |
153 | elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \ | |
154 | old_sp; }) | |
1da177e4 LT |
155 | #else |
156 | #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items)) | |
157 | #define STACK_ROUND(sp, items) \ | |
158 | (((unsigned long) (sp - items)) &~ 15UL) | |
159 | #define STACK_ALLOC(sp, len) ({ sp -= len ; sp; }) | |
160 | #endif | |
161 | ||
483fad1c NL |
162 | #ifndef ELF_BASE_PLATFORM |
163 | /* | |
164 | * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture. | |
165 | * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value | |
166 | * will be copied to the user stack in the same manner as AT_PLATFORM. | |
167 | */ | |
168 | #define ELF_BASE_PLATFORM NULL | |
169 | #endif | |
170 | ||
1da177e4 | 171 | static int |
a62c5b1b AD |
172 | create_elf_tables(struct linux_binprm *bprm, const struct elfhdr *exec, |
173 | unsigned long load_addr, unsigned long interp_load_addr, | |
174 | unsigned long e_entry) | |
1da177e4 | 175 | { |
03c6d723 | 176 | struct mm_struct *mm = current->mm; |
1da177e4 LT |
177 | unsigned long p = bprm->p; |
178 | int argc = bprm->argc; | |
179 | int envc = bprm->envc; | |
1da177e4 LT |
180 | elf_addr_t __user *sp; |
181 | elf_addr_t __user *u_platform; | |
483fad1c | 182 | elf_addr_t __user *u_base_platform; |
f06295b4 | 183 | elf_addr_t __user *u_rand_bytes; |
1da177e4 | 184 | const char *k_platform = ELF_PLATFORM; |
483fad1c | 185 | const char *k_base_platform = ELF_BASE_PLATFORM; |
f06295b4 | 186 | unsigned char k_rand_bytes[16]; |
1da177e4 LT |
187 | int items; |
188 | elf_addr_t *elf_info; | |
2347961b | 189 | elf_addr_t flags = 0; |
1f83d806 | 190 | int ei_index; |
86a264ab | 191 | const struct cred *cred = current_cred(); |
b6a2fea3 | 192 | struct vm_area_struct *vma; |
1da177e4 | 193 | |
d68c9d6a FBH |
194 | /* |
195 | * In some cases (e.g. Hyper-Threading), we want to avoid L1 | |
196 | * evictions by the processes running on the same package. One | |
197 | * thing we can do is to shuffle the initial stack for them. | |
198 | */ | |
199 | ||
200 | p = arch_align_stack(p); | |
201 | ||
1da177e4 LT |
202 | /* |
203 | * If this architecture has a platform capability string, copy it | |
204 | * to userspace. In some cases (Sparc), this info is impossible | |
205 | * for userspace to get any other way, in others (i386) it is | |
206 | * merely difficult. | |
207 | */ | |
1da177e4 LT |
208 | u_platform = NULL; |
209 | if (k_platform) { | |
210 | size_t len = strlen(k_platform) + 1; | |
211 | ||
1da177e4 | 212 | u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len); |
646e84de | 213 | if (copy_to_user(u_platform, k_platform, len)) |
1da177e4 LT |
214 | return -EFAULT; |
215 | } | |
216 | ||
483fad1c NL |
217 | /* |
218 | * If this architecture has a "base" platform capability | |
219 | * string, copy it to userspace. | |
220 | */ | |
221 | u_base_platform = NULL; | |
222 | if (k_base_platform) { | |
223 | size_t len = strlen(k_base_platform) + 1; | |
224 | ||
225 | u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len); | |
646e84de | 226 | if (copy_to_user(u_base_platform, k_base_platform, len)) |
483fad1c NL |
227 | return -EFAULT; |
228 | } | |
229 | ||
f06295b4 KC |
230 | /* |
231 | * Generate 16 random bytes for userspace PRNG seeding. | |
232 | */ | |
233 | get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes)); | |
234 | u_rand_bytes = (elf_addr_t __user *) | |
235 | STACK_ALLOC(p, sizeof(k_rand_bytes)); | |
646e84de | 236 | if (copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes))) |
f06295b4 KC |
237 | return -EFAULT; |
238 | ||
1da177e4 | 239 | /* Create the ELF interpreter info */ |
03c6d723 | 240 | elf_info = (elf_addr_t *)mm->saved_auxv; |
4f9a58d7 | 241 | /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */ |
1da177e4 | 242 | #define NEW_AUX_ENT(id, val) \ |
f4e5cc2c | 243 | do { \ |
1f83d806 AD |
244 | *elf_info++ = id; \ |
245 | *elf_info++ = val; \ | |
f4e5cc2c | 246 | } while (0) |
1da177e4 LT |
247 | |
248 | #ifdef ARCH_DLINFO | |
249 | /* | |
250 | * ARCH_DLINFO must come first so PPC can do its special alignment of | |
251 | * AUXV. | |
4f9a58d7 OH |
252 | * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in |
253 | * ARCH_DLINFO changes | |
1da177e4 LT |
254 | */ |
255 | ARCH_DLINFO; | |
256 | #endif | |
257 | NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP); | |
258 | NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE); | |
259 | NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC); | |
260 | NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff); | |
f4e5cc2c | 261 | NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr)); |
1da177e4 LT |
262 | NEW_AUX_ENT(AT_PHNUM, exec->e_phnum); |
263 | NEW_AUX_ENT(AT_BASE, interp_load_addr); | |
2347961b LV |
264 | if (bprm->interp_flags & BINPRM_FLAGS_PRESERVE_ARGV0) |
265 | flags |= AT_FLAGS_PRESERVE_ARGV0; | |
266 | NEW_AUX_ENT(AT_FLAGS, flags); | |
a62c5b1b | 267 | NEW_AUX_ENT(AT_ENTRY, e_entry); |
ebc887b2 EB |
268 | NEW_AUX_ENT(AT_UID, from_kuid_munged(cred->user_ns, cred->uid)); |
269 | NEW_AUX_ENT(AT_EUID, from_kuid_munged(cred->user_ns, cred->euid)); | |
270 | NEW_AUX_ENT(AT_GID, from_kgid_munged(cred->user_ns, cred->gid)); | |
271 | NEW_AUX_ENT(AT_EGID, from_kgid_munged(cred->user_ns, cred->egid)); | |
c425e189 | 272 | NEW_AUX_ENT(AT_SECURE, bprm->secureexec); |
f06295b4 | 273 | NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes); |
2171364d MN |
274 | #ifdef ELF_HWCAP2 |
275 | NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2); | |
276 | #endif | |
65191087 | 277 | NEW_AUX_ENT(AT_EXECFN, bprm->exec); |
1da177e4 | 278 | if (k_platform) { |
f4e5cc2c | 279 | NEW_AUX_ENT(AT_PLATFORM, |
785d5570 | 280 | (elf_addr_t)(unsigned long)u_platform); |
1da177e4 | 281 | } |
483fad1c NL |
282 | if (k_base_platform) { |
283 | NEW_AUX_ENT(AT_BASE_PLATFORM, | |
284 | (elf_addr_t)(unsigned long)u_base_platform); | |
285 | } | |
b8a61c9e EB |
286 | if (bprm->have_execfd) { |
287 | NEW_AUX_ENT(AT_EXECFD, bprm->execfd); | |
1da177e4 LT |
288 | } |
289 | #undef NEW_AUX_ENT | |
290 | /* AT_NULL is zero; clear the rest too */ | |
03c6d723 AD |
291 | memset(elf_info, 0, (char *)mm->saved_auxv + |
292 | sizeof(mm->saved_auxv) - (char *)elf_info); | |
1da177e4 LT |
293 | |
294 | /* And advance past the AT_NULL entry. */ | |
1f83d806 | 295 | elf_info += 2; |
1da177e4 | 296 | |
03c6d723 | 297 | ei_index = elf_info - (elf_addr_t *)mm->saved_auxv; |
1da177e4 LT |
298 | sp = STACK_ADD(p, ei_index); |
299 | ||
d20894a2 | 300 | items = (argc + 1) + (envc + 1) + 1; |
1da177e4 LT |
301 | bprm->p = STACK_ROUND(sp, items); |
302 | ||
303 | /* Point sp at the lowest address on the stack */ | |
304 | #ifdef CONFIG_STACK_GROWSUP | |
305 | sp = (elf_addr_t __user *)bprm->p - items - ei_index; | |
f4e5cc2c | 306 | bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */ |
1da177e4 LT |
307 | #else |
308 | sp = (elf_addr_t __user *)bprm->p; | |
309 | #endif | |
310 | ||
b6a2fea3 OW |
311 | |
312 | /* | |
313 | * Grow the stack manually; some architectures have a limit on how | |
314 | * far ahead a user-space access may be in order to grow the stack. | |
315 | */ | |
b2767d97 JH |
316 | if (mmap_read_lock_killable(mm)) |
317 | return -EINTR; | |
03c6d723 | 318 | vma = find_extend_vma(mm, bprm->p); |
b2767d97 | 319 | mmap_read_unlock(mm); |
b6a2fea3 OW |
320 | if (!vma) |
321 | return -EFAULT; | |
322 | ||
1da177e4 | 323 | /* Now, let's put argc (and argv, envp if appropriate) on the stack */ |
646e84de | 324 | if (put_user(argc, sp++)) |
1da177e4 | 325 | return -EFAULT; |
1da177e4 | 326 | |
67c6777a | 327 | /* Populate list of argv pointers back to argv strings. */ |
03c6d723 | 328 | p = mm->arg_end = mm->arg_start; |
1da177e4 LT |
329 | while (argc-- > 0) { |
330 | size_t len; | |
646e84de | 331 | if (put_user((elf_addr_t)p, sp++)) |
841d5fb7 | 332 | return -EFAULT; |
b6a2fea3 OW |
333 | len = strnlen_user((void __user *)p, MAX_ARG_STRLEN); |
334 | if (!len || len > MAX_ARG_STRLEN) | |
23c4971e | 335 | return -EINVAL; |
1da177e4 LT |
336 | p += len; |
337 | } | |
646e84de | 338 | if (put_user(0, sp++)) |
1da177e4 | 339 | return -EFAULT; |
03c6d723 | 340 | mm->arg_end = p; |
67c6777a KC |
341 | |
342 | /* Populate list of envp pointers back to envp strings. */ | |
03c6d723 | 343 | mm->env_end = mm->env_start = p; |
1da177e4 LT |
344 | while (envc-- > 0) { |
345 | size_t len; | |
646e84de | 346 | if (put_user((elf_addr_t)p, sp++)) |
841d5fb7 | 347 | return -EFAULT; |
b6a2fea3 OW |
348 | len = strnlen_user((void __user *)p, MAX_ARG_STRLEN); |
349 | if (!len || len > MAX_ARG_STRLEN) | |
23c4971e | 350 | return -EINVAL; |
1da177e4 LT |
351 | p += len; |
352 | } | |
646e84de | 353 | if (put_user(0, sp++)) |
1da177e4 | 354 | return -EFAULT; |
03c6d723 | 355 | mm->env_end = p; |
1da177e4 LT |
356 | |
357 | /* Put the elf_info on the stack in the right place. */ | |
03c6d723 | 358 | if (copy_to_user(sp, mm->saved_auxv, ei_index * sizeof(elf_addr_t))) |
1da177e4 LT |
359 | return -EFAULT; |
360 | return 0; | |
361 | } | |
362 | ||
1da177e4 | 363 | static unsigned long elf_map(struct file *filep, unsigned long addr, |
49ac9819 | 364 | const struct elf_phdr *eppnt, int prot, int type, |
cc503c1b | 365 | unsigned long total_size) |
1da177e4 LT |
366 | { |
367 | unsigned long map_addr; | |
cc503c1b JK |
368 | unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr); |
369 | unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr); | |
370 | addr = ELF_PAGESTART(addr); | |
371 | size = ELF_PAGEALIGN(size); | |
1da177e4 | 372 | |
dda6ebde DG |
373 | /* mmap() will return -EINVAL if given a zero size, but a |
374 | * segment with zero filesize is perfectly valid */ | |
cc503c1b JK |
375 | if (!size) |
376 | return addr; | |
377 | ||
cc503c1b JK |
378 | /* |
379 | * total_size is the size of the ELF (interpreter) image. | |
380 | * The _first_ mmap needs to know the full size, otherwise | |
381 | * randomization might put this image into an overlapping | |
382 | * position with the ELF binary image. (since size < total_size) | |
383 | * So we first map the 'big' image - and unmap the remainder at | |
384 | * the end. (which unmap is needed for ELF images with holes.) | |
385 | */ | |
386 | if (total_size) { | |
387 | total_size = ELF_PAGEALIGN(total_size); | |
5a5e4c2e | 388 | map_addr = vm_mmap(filep, addr, total_size, prot, type, off); |
cc503c1b | 389 | if (!BAD_ADDR(map_addr)) |
5a5e4c2e | 390 | vm_munmap(map_addr+size, total_size-size); |
cc503c1b | 391 | } else |
5a5e4c2e | 392 | map_addr = vm_mmap(filep, addr, size, prot, type, off); |
cc503c1b | 393 | |
d23a61ee TH |
394 | if ((type & MAP_FIXED_NOREPLACE) && |
395 | PTR_ERR((void *)map_addr) == -EEXIST) | |
396 | pr_info("%d (%s): Uhuuh, elf segment at %px requested but the memory is mapped already\n", | |
397 | task_pid_nr(current), current->comm, (void *)addr); | |
4ed28639 | 398 | |
1da177e4 LT |
399 | return(map_addr); |
400 | } | |
401 | ||
49ac9819 | 402 | static unsigned long total_mapping_size(const struct elf_phdr *cmds, int nr) |
cc503c1b JK |
403 | { |
404 | int i, first_idx = -1, last_idx = -1; | |
405 | ||
406 | for (i = 0; i < nr; i++) { | |
407 | if (cmds[i].p_type == PT_LOAD) { | |
408 | last_idx = i; | |
409 | if (first_idx == -1) | |
410 | first_idx = i; | |
411 | } | |
412 | } | |
413 | if (first_idx == -1) | |
414 | return 0; | |
415 | ||
416 | return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz - | |
417 | ELF_PAGESTART(cmds[first_idx].p_vaddr); | |
418 | } | |
419 | ||
658c0335 AD |
420 | static int elf_read(struct file *file, void *buf, size_t len, loff_t pos) |
421 | { | |
422 | ssize_t rv; | |
423 | ||
424 | rv = kernel_read(file, buf, len, &pos); | |
425 | if (unlikely(rv != len)) { | |
426 | return (rv < 0) ? rv : -EIO; | |
427 | } | |
428 | return 0; | |
429 | } | |
430 | ||
ce81bb25 CK |
431 | static unsigned long maximum_alignment(struct elf_phdr *cmds, int nr) |
432 | { | |
433 | unsigned long alignment = 0; | |
434 | int i; | |
435 | ||
436 | for (i = 0; i < nr; i++) { | |
437 | if (cmds[i].p_type == PT_LOAD) { | |
438 | unsigned long p_align = cmds[i].p_align; | |
439 | ||
440 | /* skip non-power of two alignments as invalid */ | |
441 | if (!is_power_of_2(p_align)) | |
442 | continue; | |
443 | alignment = max(alignment, p_align); | |
444 | } | |
445 | } | |
446 | ||
447 | /* ensure we align to at least one page */ | |
448 | return ELF_PAGEALIGN(alignment); | |
449 | } | |
450 | ||
6a8d3894 PB |
451 | /** |
452 | * load_elf_phdrs() - load ELF program headers | |
453 | * @elf_ex: ELF header of the binary whose program headers should be loaded | |
454 | * @elf_file: the opened ELF binary file | |
455 | * | |
456 | * Loads ELF program headers from the binary file elf_file, which has the ELF | |
457 | * header pointed to by elf_ex, into a newly allocated array. The caller is | |
458 | * responsible for freeing the allocated data. Returns an ERR_PTR upon failure. | |
459 | */ | |
49ac9819 | 460 | static struct elf_phdr *load_elf_phdrs(const struct elfhdr *elf_ex, |
6a8d3894 PB |
461 | struct file *elf_file) |
462 | { | |
463 | struct elf_phdr *elf_phdata = NULL; | |
faf1c315 | 464 | int retval, err = -1; |
faf1c315 | 465 | unsigned int size; |
6a8d3894 PB |
466 | |
467 | /* | |
468 | * If the size of this structure has changed, then punt, since | |
469 | * we will be doing the wrong thing. | |
470 | */ | |
471 | if (elf_ex->e_phentsize != sizeof(struct elf_phdr)) | |
472 | goto out; | |
473 | ||
474 | /* Sanity check the number of program headers... */ | |
6a8d3894 PB |
475 | /* ...and their total size. */ |
476 | size = sizeof(struct elf_phdr) * elf_ex->e_phnum; | |
faf1c315 | 477 | if (size == 0 || size > 65536 || size > ELF_MIN_ALIGN) |
6a8d3894 PB |
478 | goto out; |
479 | ||
480 | elf_phdata = kmalloc(size, GFP_KERNEL); | |
481 | if (!elf_phdata) | |
482 | goto out; | |
483 | ||
484 | /* Read in the program headers */ | |
658c0335 AD |
485 | retval = elf_read(elf_file, elf_phdata, size, elf_ex->e_phoff); |
486 | if (retval < 0) { | |
487 | err = retval; | |
6a8d3894 PB |
488 | goto out; |
489 | } | |
490 | ||
491 | /* Success! */ | |
492 | err = 0; | |
493 | out: | |
494 | if (err) { | |
495 | kfree(elf_phdata); | |
496 | elf_phdata = NULL; | |
497 | } | |
498 | return elf_phdata; | |
499 | } | |
cc503c1b | 500 | |
774c105e PB |
501 | #ifndef CONFIG_ARCH_BINFMT_ELF_STATE |
502 | ||
503 | /** | |
504 | * struct arch_elf_state - arch-specific ELF loading state | |
505 | * | |
506 | * This structure is used to preserve architecture specific data during | |
507 | * the loading of an ELF file, throughout the checking of architecture | |
508 | * specific ELF headers & through to the point where the ELF load is | |
509 | * known to be proceeding (ie. SET_PERSONALITY). | |
510 | * | |
511 | * This implementation is a dummy for architectures which require no | |
512 | * specific state. | |
513 | */ | |
514 | struct arch_elf_state { | |
515 | }; | |
516 | ||
517 | #define INIT_ARCH_ELF_STATE {} | |
518 | ||
519 | /** | |
520 | * arch_elf_pt_proc() - check a PT_LOPROC..PT_HIPROC ELF program header | |
521 | * @ehdr: The main ELF header | |
522 | * @phdr: The program header to check | |
523 | * @elf: The open ELF file | |
524 | * @is_interp: True if the phdr is from the interpreter of the ELF being | |
525 | * loaded, else false. | |
526 | * @state: Architecture-specific state preserved throughout the process | |
527 | * of loading the ELF. | |
528 | * | |
529 | * Inspects the program header phdr to validate its correctness and/or | |
530 | * suitability for the system. Called once per ELF program header in the | |
531 | * range PT_LOPROC to PT_HIPROC, for both the ELF being loaded and its | |
532 | * interpreter. | |
533 | * | |
534 | * Return: Zero to proceed with the ELF load, non-zero to fail the ELF load | |
535 | * with that return code. | |
536 | */ | |
537 | static inline int arch_elf_pt_proc(struct elfhdr *ehdr, | |
538 | struct elf_phdr *phdr, | |
539 | struct file *elf, bool is_interp, | |
540 | struct arch_elf_state *state) | |
541 | { | |
542 | /* Dummy implementation, always proceed */ | |
543 | return 0; | |
544 | } | |
545 | ||
546 | /** | |
54d15714 | 547 | * arch_check_elf() - check an ELF executable |
774c105e PB |
548 | * @ehdr: The main ELF header |
549 | * @has_interp: True if the ELF has an interpreter, else false. | |
eb4bc076 | 550 | * @interp_ehdr: The interpreter's ELF header |
774c105e PB |
551 | * @state: Architecture-specific state preserved throughout the process |
552 | * of loading the ELF. | |
553 | * | |
554 | * Provides a final opportunity for architecture code to reject the loading | |
555 | * of the ELF & cause an exec syscall to return an error. This is called after | |
556 | * all program headers to be checked by arch_elf_pt_proc have been. | |
557 | * | |
558 | * Return: Zero to proceed with the ELF load, non-zero to fail the ELF load | |
559 | * with that return code. | |
560 | */ | |
561 | static inline int arch_check_elf(struct elfhdr *ehdr, bool has_interp, | |
eb4bc076 | 562 | struct elfhdr *interp_ehdr, |
774c105e PB |
563 | struct arch_elf_state *state) |
564 | { | |
565 | /* Dummy implementation, always proceed */ | |
566 | return 0; | |
567 | } | |
568 | ||
569 | #endif /* !CONFIG_ARCH_BINFMT_ELF_STATE */ | |
cc503c1b | 570 | |
fe0f6766 DM |
571 | static inline int make_prot(u32 p_flags, struct arch_elf_state *arch_state, |
572 | bool has_interp, bool is_interp) | |
d8e7cb39 AD |
573 | { |
574 | int prot = 0; | |
575 | ||
576 | if (p_flags & PF_R) | |
577 | prot |= PROT_READ; | |
578 | if (p_flags & PF_W) | |
579 | prot |= PROT_WRITE; | |
580 | if (p_flags & PF_X) | |
581 | prot |= PROT_EXEC; | |
fe0f6766 DM |
582 | |
583 | return arch_elf_adjust_prot(prot, arch_state, has_interp, is_interp); | |
d8e7cb39 AD |
584 | } |
585 | ||
1da177e4 LT |
586 | /* This is much more generalized than the library routine read function, |
587 | so we keep this separate. Technically the library read function | |
588 | is only provided so that we can read a.out libraries that have | |
589 | an ELF header */ | |
590 | ||
f4e5cc2c | 591 | static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex, |
81696d5d | 592 | struct file *interpreter, |
fe0f6766 DM |
593 | unsigned long no_base, struct elf_phdr *interp_elf_phdata, |
594 | struct arch_elf_state *arch_state) | |
1da177e4 | 595 | { |
1da177e4 LT |
596 | struct elf_phdr *eppnt; |
597 | unsigned long load_addr = 0; | |
598 | int load_addr_set = 0; | |
599 | unsigned long last_bss = 0, elf_bss = 0; | |
16e72e9b | 600 | int bss_prot = 0; |
1da177e4 | 601 | unsigned long error = ~0UL; |
cc503c1b | 602 | unsigned long total_size; |
6a8d3894 | 603 | int i; |
1da177e4 LT |
604 | |
605 | /* First of all, some simple consistency checks */ | |
606 | if (interp_elf_ex->e_type != ET_EXEC && | |
607 | interp_elf_ex->e_type != ET_DYN) | |
608 | goto out; | |
4755200b NP |
609 | if (!elf_check_arch(interp_elf_ex) || |
610 | elf_check_fdpic(interp_elf_ex)) | |
1da177e4 | 611 | goto out; |
72c2d531 | 612 | if (!interpreter->f_op->mmap) |
1da177e4 LT |
613 | goto out; |
614 | ||
a9d9ef13 PB |
615 | total_size = total_mapping_size(interp_elf_phdata, |
616 | interp_elf_ex->e_phnum); | |
cc503c1b JK |
617 | if (!total_size) { |
618 | error = -EINVAL; | |
a9d9ef13 | 619 | goto out; |
cc503c1b JK |
620 | } |
621 | ||
a9d9ef13 | 622 | eppnt = interp_elf_phdata; |
f4e5cc2c JJ |
623 | for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) { |
624 | if (eppnt->p_type == PT_LOAD) { | |
4589ff7c | 625 | int elf_type = MAP_PRIVATE; |
fe0f6766 DM |
626 | int elf_prot = make_prot(eppnt->p_flags, arch_state, |
627 | true, true); | |
f4e5cc2c JJ |
628 | unsigned long vaddr = 0; |
629 | unsigned long k, map_addr; | |
630 | ||
f4e5cc2c JJ |
631 | vaddr = eppnt->p_vaddr; |
632 | if (interp_elf_ex->e_type == ET_EXEC || load_addr_set) | |
4ed28639 | 633 | elf_type |= MAP_FIXED_NOREPLACE; |
cc503c1b JK |
634 | else if (no_base && interp_elf_ex->e_type == ET_DYN) |
635 | load_addr = -vaddr; | |
f4e5cc2c JJ |
636 | |
637 | map_addr = elf_map(interpreter, load_addr + vaddr, | |
bb1ad820 | 638 | eppnt, elf_prot, elf_type, total_size); |
cc503c1b | 639 | total_size = 0; |
f4e5cc2c JJ |
640 | error = map_addr; |
641 | if (BAD_ADDR(map_addr)) | |
a9d9ef13 | 642 | goto out; |
f4e5cc2c JJ |
643 | |
644 | if (!load_addr_set && | |
645 | interp_elf_ex->e_type == ET_DYN) { | |
646 | load_addr = map_addr - ELF_PAGESTART(vaddr); | |
647 | load_addr_set = 1; | |
648 | } | |
649 | ||
650 | /* | |
651 | * Check to see if the section's size will overflow the | |
652 | * allowed task size. Note that p_filesz must always be | |
653 | * <= p_memsize so it's only necessary to check p_memsz. | |
654 | */ | |
655 | k = load_addr + eppnt->p_vaddr; | |
ce51059b | 656 | if (BAD_ADDR(k) || |
f4e5cc2c JJ |
657 | eppnt->p_filesz > eppnt->p_memsz || |
658 | eppnt->p_memsz > TASK_SIZE || | |
659 | TASK_SIZE - eppnt->p_memsz < k) { | |
660 | error = -ENOMEM; | |
a9d9ef13 | 661 | goto out; |
f4e5cc2c JJ |
662 | } |
663 | ||
664 | /* | |
665 | * Find the end of the file mapping for this phdr, and | |
666 | * keep track of the largest address we see for this. | |
667 | */ | |
668 | k = load_addr + eppnt->p_vaddr + eppnt->p_filesz; | |
669 | if (k > elf_bss) | |
670 | elf_bss = k; | |
671 | ||
672 | /* | |
673 | * Do the same thing for the memory mapping - between | |
674 | * elf_bss and last_bss is the bss section. | |
675 | */ | |
0036d1f7 | 676 | k = load_addr + eppnt->p_vaddr + eppnt->p_memsz; |
16e72e9b | 677 | if (k > last_bss) { |
f4e5cc2c | 678 | last_bss = k; |
16e72e9b DV |
679 | bss_prot = elf_prot; |
680 | } | |
f4e5cc2c | 681 | } |
1da177e4 LT |
682 | } |
683 | ||
0036d1f7 KC |
684 | /* |
685 | * Now fill out the bss section: first pad the last page from | |
686 | * the file up to the page boundary, and zero it from elf_bss | |
687 | * up to the end of the page. | |
688 | */ | |
689 | if (padzero(elf_bss)) { | |
690 | error = -EFAULT; | |
691 | goto out; | |
692 | } | |
693 | /* | |
694 | * Next, align both the file and mem bss up to the page size, | |
695 | * since this is where elf_bss was just zeroed up to, and where | |
16e72e9b | 696 | * last_bss will end after the vm_brk_flags() below. |
0036d1f7 KC |
697 | */ |
698 | elf_bss = ELF_PAGEALIGN(elf_bss); | |
699 | last_bss = ELF_PAGEALIGN(last_bss); | |
700 | /* Finally, if there is still more bss to allocate, do it. */ | |
752015d1 | 701 | if (last_bss > elf_bss) { |
16e72e9b DV |
702 | error = vm_brk_flags(elf_bss, last_bss - elf_bss, |
703 | bss_prot & PROT_EXEC ? VM_EXEC : 0); | |
5d22fc25 | 704 | if (error) |
a9d9ef13 | 705 | goto out; |
1da177e4 LT |
706 | } |
707 | ||
cc503c1b | 708 | error = load_addr; |
1da177e4 LT |
709 | out: |
710 | return error; | |
711 | } | |
712 | ||
1da177e4 LT |
713 | /* |
714 | * These are the functions used to load ELF style executables and shared | |
715 | * libraries. There is no binary dependent code anywhere else. | |
716 | */ | |
717 | ||
00e19cee DM |
718 | static int parse_elf_property(const char *data, size_t *off, size_t datasz, |
719 | struct arch_elf_state *arch, | |
720 | bool have_prev_type, u32 *prev_type) | |
721 | { | |
722 | size_t o, step; | |
723 | const struct gnu_property *pr; | |
724 | int ret; | |
725 | ||
726 | if (*off == datasz) | |
727 | return -ENOENT; | |
728 | ||
729 | if (WARN_ON_ONCE(*off > datasz || *off % ELF_GNU_PROPERTY_ALIGN)) | |
730 | return -EIO; | |
731 | o = *off; | |
732 | datasz -= *off; | |
733 | ||
734 | if (datasz < sizeof(*pr)) | |
735 | return -ENOEXEC; | |
736 | pr = (const struct gnu_property *)(data + o); | |
737 | o += sizeof(*pr); | |
738 | datasz -= sizeof(*pr); | |
739 | ||
740 | if (pr->pr_datasz > datasz) | |
741 | return -ENOEXEC; | |
742 | ||
743 | WARN_ON_ONCE(o % ELF_GNU_PROPERTY_ALIGN); | |
744 | step = round_up(pr->pr_datasz, ELF_GNU_PROPERTY_ALIGN); | |
745 | if (step > datasz) | |
746 | return -ENOEXEC; | |
747 | ||
748 | /* Properties are supposed to be unique and sorted on pr_type: */ | |
749 | if (have_prev_type && pr->pr_type <= *prev_type) | |
750 | return -ENOEXEC; | |
751 | *prev_type = pr->pr_type; | |
752 | ||
753 | ret = arch_parse_elf_property(pr->pr_type, data + o, | |
754 | pr->pr_datasz, ELF_COMPAT, arch); | |
755 | if (ret) | |
756 | return ret; | |
757 | ||
758 | *off = o + step; | |
759 | return 0; | |
760 | } | |
761 | ||
762 | #define NOTE_DATA_SZ SZ_1K | |
763 | #define GNU_PROPERTY_TYPE_0_NAME "GNU" | |
764 | #define NOTE_NAME_SZ (sizeof(GNU_PROPERTY_TYPE_0_NAME)) | |
765 | ||
766 | static int parse_elf_properties(struct file *f, const struct elf_phdr *phdr, | |
767 | struct arch_elf_state *arch) | |
768 | { | |
769 | union { | |
770 | struct elf_note nhdr; | |
771 | char data[NOTE_DATA_SZ]; | |
772 | } note; | |
773 | loff_t pos; | |
774 | ssize_t n; | |
775 | size_t off, datasz; | |
776 | int ret; | |
777 | bool have_prev_type; | |
778 | u32 prev_type; | |
779 | ||
780 | if (!IS_ENABLED(CONFIG_ARCH_USE_GNU_PROPERTY) || !phdr) | |
781 | return 0; | |
782 | ||
783 | /* load_elf_binary() shouldn't call us unless this is true... */ | |
784 | if (WARN_ON_ONCE(phdr->p_type != PT_GNU_PROPERTY)) | |
785 | return -ENOEXEC; | |
786 | ||
787 | /* If the properties are crazy large, that's too bad (for now): */ | |
788 | if (phdr->p_filesz > sizeof(note)) | |
789 | return -ENOEXEC; | |
790 | ||
791 | pos = phdr->p_offset; | |
792 | n = kernel_read(f, ¬e, phdr->p_filesz, &pos); | |
793 | ||
794 | BUILD_BUG_ON(sizeof(note) < sizeof(note.nhdr) + NOTE_NAME_SZ); | |
795 | if (n < 0 || n < sizeof(note.nhdr) + NOTE_NAME_SZ) | |
796 | return -EIO; | |
797 | ||
798 | if (note.nhdr.n_type != NT_GNU_PROPERTY_TYPE_0 || | |
799 | note.nhdr.n_namesz != NOTE_NAME_SZ || | |
800 | strncmp(note.data + sizeof(note.nhdr), | |
801 | GNU_PROPERTY_TYPE_0_NAME, n - sizeof(note.nhdr))) | |
802 | return -ENOEXEC; | |
803 | ||
804 | off = round_up(sizeof(note.nhdr) + NOTE_NAME_SZ, | |
805 | ELF_GNU_PROPERTY_ALIGN); | |
806 | if (off > n) | |
807 | return -ENOEXEC; | |
808 | ||
809 | if (note.nhdr.n_descsz > n - off) | |
810 | return -ENOEXEC; | |
811 | datasz = off + note.nhdr.n_descsz; | |
812 | ||
813 | have_prev_type = false; | |
814 | do { | |
815 | ret = parse_elf_property(note.data, &off, datasz, arch, | |
816 | have_prev_type, &prev_type); | |
817 | have_prev_type = true; | |
818 | } while (!ret); | |
819 | ||
820 | return ret == -ENOENT ? 0 : ret; | |
821 | } | |
822 | ||
71613c3b | 823 | static int load_elf_binary(struct linux_binprm *bprm) |
1da177e4 LT |
824 | { |
825 | struct file *interpreter = NULL; /* to shut gcc up */ | |
826 | unsigned long load_addr = 0, load_bias = 0; | |
827 | int load_addr_set = 0; | |
1da177e4 | 828 | unsigned long error; |
a9d9ef13 | 829 | struct elf_phdr *elf_ppnt, *elf_phdata, *interp_elf_phdata = NULL; |
00e19cee | 830 | struct elf_phdr *elf_property_phdata = NULL; |
1da177e4 | 831 | unsigned long elf_bss, elf_brk; |
16e72e9b | 832 | int bss_prot = 0; |
1da177e4 | 833 | int retval, i; |
cc503c1b | 834 | unsigned long elf_entry; |
a62c5b1b | 835 | unsigned long e_entry; |
cc503c1b | 836 | unsigned long interp_load_addr = 0; |
1da177e4 | 837 | unsigned long start_code, end_code, start_data, end_data; |
1a530a6f | 838 | unsigned long reloc_func_desc __maybe_unused = 0; |
8de61e69 | 839 | int executable_stack = EXSTACK_DEFAULT; |
a62c5b1b | 840 | struct elfhdr *elf_ex = (struct elfhdr *)bprm->buf; |
0693ffeb | 841 | struct elfhdr *interp_elf_ex = NULL; |
774c105e | 842 | struct arch_elf_state arch_state = INIT_ARCH_ELF_STATE; |
03c6d723 | 843 | struct mm_struct *mm; |
249b08e4 | 844 | struct pt_regs *regs; |
1da177e4 | 845 | |
1da177e4 LT |
846 | retval = -ENOEXEC; |
847 | /* First of all, some simple consistency checks */ | |
a62c5b1b | 848 | if (memcmp(elf_ex->e_ident, ELFMAG, SELFMAG) != 0) |
1da177e4 LT |
849 | goto out; |
850 | ||
a62c5b1b | 851 | if (elf_ex->e_type != ET_EXEC && elf_ex->e_type != ET_DYN) |
1da177e4 | 852 | goto out; |
a62c5b1b | 853 | if (!elf_check_arch(elf_ex)) |
1da177e4 | 854 | goto out; |
a62c5b1b | 855 | if (elf_check_fdpic(elf_ex)) |
4755200b | 856 | goto out; |
72c2d531 | 857 | if (!bprm->file->f_op->mmap) |
1da177e4 LT |
858 | goto out; |
859 | ||
a62c5b1b | 860 | elf_phdata = load_elf_phdrs(elf_ex, bprm->file); |
1da177e4 LT |
861 | if (!elf_phdata) |
862 | goto out; | |
863 | ||
1da177e4 | 864 | elf_ppnt = elf_phdata; |
a62c5b1b | 865 | for (i = 0; i < elf_ex->e_phnum; i++, elf_ppnt++) { |
be0deb58 | 866 | char *elf_interpreter; |
1da177e4 | 867 | |
00e19cee DM |
868 | if (elf_ppnt->p_type == PT_GNU_PROPERTY) { |
869 | elf_property_phdata = elf_ppnt; | |
870 | continue; | |
871 | } | |
872 | ||
be0deb58 AD |
873 | if (elf_ppnt->p_type != PT_INTERP) |
874 | continue; | |
1fb84496 | 875 | |
be0deb58 AD |
876 | /* |
877 | * This is the program interpreter used for shared libraries - | |
878 | * for now assume that this is an a.out format binary. | |
879 | */ | |
880 | retval = -ENOEXEC; | |
881 | if (elf_ppnt->p_filesz > PATH_MAX || elf_ppnt->p_filesz < 2) | |
882 | goto out_free_ph; | |
1da177e4 | 883 | |
be0deb58 AD |
884 | retval = -ENOMEM; |
885 | elf_interpreter = kmalloc(elf_ppnt->p_filesz, GFP_KERNEL); | |
886 | if (!elf_interpreter) | |
887 | goto out_free_ph; | |
cc338010 | 888 | |
658c0335 AD |
889 | retval = elf_read(bprm->file, elf_interpreter, elf_ppnt->p_filesz, |
890 | elf_ppnt->p_offset); | |
891 | if (retval < 0) | |
be0deb58 | 892 | goto out_free_interp; |
be0deb58 AD |
893 | /* make sure path is NULL terminated */ |
894 | retval = -ENOEXEC; | |
895 | if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0') | |
896 | goto out_free_interp; | |
897 | ||
898 | interpreter = open_exec(elf_interpreter); | |
899 | kfree(elf_interpreter); | |
900 | retval = PTR_ERR(interpreter); | |
901 | if (IS_ERR(interpreter)) | |
cc338010 | 902 | goto out_free_ph; |
be0deb58 AD |
903 | |
904 | /* | |
905 | * If the binary is not readable then enforce mm->dumpable = 0 | |
906 | * regardless of the interpreter's permissions. | |
907 | */ | |
908 | would_dump(bprm, interpreter); | |
909 | ||
0693ffeb AD |
910 | interp_elf_ex = kmalloc(sizeof(*interp_elf_ex), GFP_KERNEL); |
911 | if (!interp_elf_ex) { | |
912 | retval = -ENOMEM; | |
913 | goto out_free_ph; | |
914 | } | |
915 | ||
be0deb58 | 916 | /* Get the exec headers */ |
c69bcc93 AD |
917 | retval = elf_read(interpreter, interp_elf_ex, |
918 | sizeof(*interp_elf_ex), 0); | |
658c0335 | 919 | if (retval < 0) |
be0deb58 | 920 | goto out_free_dentry; |
be0deb58 AD |
921 | |
922 | break; | |
923 | ||
924 | out_free_interp: | |
925 | kfree(elf_interpreter); | |
926 | goto out_free_ph; | |
1da177e4 LT |
927 | } |
928 | ||
929 | elf_ppnt = elf_phdata; | |
a62c5b1b | 930 | for (i = 0; i < elf_ex->e_phnum; i++, elf_ppnt++) |
774c105e PB |
931 | switch (elf_ppnt->p_type) { |
932 | case PT_GNU_STACK: | |
1da177e4 LT |
933 | if (elf_ppnt->p_flags & PF_X) |
934 | executable_stack = EXSTACK_ENABLE_X; | |
935 | else | |
936 | executable_stack = EXSTACK_DISABLE_X; | |
937 | break; | |
774c105e PB |
938 | |
939 | case PT_LOPROC ... PT_HIPROC: | |
a62c5b1b | 940 | retval = arch_elf_pt_proc(elf_ex, elf_ppnt, |
774c105e PB |
941 | bprm->file, false, |
942 | &arch_state); | |
943 | if (retval) | |
944 | goto out_free_dentry; | |
945 | break; | |
1da177e4 | 946 | } |
1da177e4 LT |
947 | |
948 | /* Some simple consistency checks for the interpreter */ | |
cc338010 | 949 | if (interpreter) { |
1da177e4 | 950 | retval = -ELIBBAD; |
d20894a2 | 951 | /* Not an ELF interpreter */ |
c69bcc93 | 952 | if (memcmp(interp_elf_ex->e_ident, ELFMAG, SELFMAG) != 0) |
1da177e4 | 953 | goto out_free_dentry; |
1da177e4 | 954 | /* Verify the interpreter has a valid arch */ |
c69bcc93 AD |
955 | if (!elf_check_arch(interp_elf_ex) || |
956 | elf_check_fdpic(interp_elf_ex)) | |
1da177e4 | 957 | goto out_free_dentry; |
a9d9ef13 PB |
958 | |
959 | /* Load the interpreter program headers */ | |
c69bcc93 | 960 | interp_elf_phdata = load_elf_phdrs(interp_elf_ex, |
a9d9ef13 PB |
961 | interpreter); |
962 | if (!interp_elf_phdata) | |
963 | goto out_free_dentry; | |
774c105e PB |
964 | |
965 | /* Pass PT_LOPROC..PT_HIPROC headers to arch code */ | |
00e19cee | 966 | elf_property_phdata = NULL; |
774c105e | 967 | elf_ppnt = interp_elf_phdata; |
c69bcc93 | 968 | for (i = 0; i < interp_elf_ex->e_phnum; i++, elf_ppnt++) |
774c105e | 969 | switch (elf_ppnt->p_type) { |
00e19cee DM |
970 | case PT_GNU_PROPERTY: |
971 | elf_property_phdata = elf_ppnt; | |
972 | break; | |
973 | ||
774c105e | 974 | case PT_LOPROC ... PT_HIPROC: |
c69bcc93 | 975 | retval = arch_elf_pt_proc(interp_elf_ex, |
774c105e PB |
976 | elf_ppnt, interpreter, |
977 | true, &arch_state); | |
978 | if (retval) | |
979 | goto out_free_dentry; | |
980 | break; | |
981 | } | |
1da177e4 LT |
982 | } |
983 | ||
00e19cee DM |
984 | retval = parse_elf_properties(interpreter ?: bprm->file, |
985 | elf_property_phdata, &arch_state); | |
986 | if (retval) | |
987 | goto out_free_dentry; | |
988 | ||
774c105e PB |
989 | /* |
990 | * Allow arch code to reject the ELF at this point, whilst it's | |
991 | * still possible to return an error to the code that invoked | |
992 | * the exec syscall. | |
993 | */ | |
a62c5b1b | 994 | retval = arch_check_elf(elf_ex, |
c69bcc93 | 995 | !!interpreter, interp_elf_ex, |
eb4bc076 | 996 | &arch_state); |
774c105e PB |
997 | if (retval) |
998 | goto out_free_dentry; | |
999 | ||
1da177e4 | 1000 | /* Flush all traces of the currently running executable */ |
2388777a | 1001 | retval = begin_new_exec(bprm); |
1da177e4 LT |
1002 | if (retval) |
1003 | goto out_free_dentry; | |
1004 | ||
1da177e4 LT |
1005 | /* Do this immediately, since STACK_TOP as used in setup_arg_pages |
1006 | may depend on the personality. */ | |
a62c5b1b AD |
1007 | SET_PERSONALITY2(*elf_ex, &arch_state); |
1008 | if (elf_read_implies_exec(*elf_ex, executable_stack)) | |
1da177e4 LT |
1009 | current->personality |= READ_IMPLIES_EXEC; |
1010 | ||
f4e5cc2c | 1011 | if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) |
1da177e4 | 1012 | current->flags |= PF_RANDOMIZE; |
221af7f8 LT |
1013 | |
1014 | setup_new_exec(bprm); | |
1da177e4 LT |
1015 | |
1016 | /* Do this so that we can load the interpreter, if need be. We will | |
1017 | change some of these later */ | |
1da177e4 LT |
1018 | retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP), |
1019 | executable_stack); | |
19d860a1 | 1020 | if (retval < 0) |
1da177e4 | 1021 | goto out_free_dentry; |
1da177e4 | 1022 | |
85264316 AD |
1023 | elf_bss = 0; |
1024 | elf_brk = 0; | |
1025 | ||
1026 | start_code = ~0UL; | |
1027 | end_code = 0; | |
1028 | start_data = 0; | |
1029 | end_data = 0; | |
1030 | ||
af901ca1 | 1031 | /* Now we do a little grungy work by mmapping the ELF image into |
cc503c1b | 1032 | the correct location in memory. */ |
f4e5cc2c | 1033 | for(i = 0, elf_ppnt = elf_phdata; |
a62c5b1b | 1034 | i < elf_ex->e_phnum; i++, elf_ppnt++) { |
b212921b | 1035 | int elf_prot, elf_flags; |
1da177e4 | 1036 | unsigned long k, vaddr; |
a87938b2 | 1037 | unsigned long total_size = 0; |
ce81bb25 | 1038 | unsigned long alignment; |
1da177e4 LT |
1039 | |
1040 | if (elf_ppnt->p_type != PT_LOAD) | |
1041 | continue; | |
1042 | ||
1043 | if (unlikely (elf_brk > elf_bss)) { | |
1044 | unsigned long nbyte; | |
1045 | ||
1046 | /* There was a PT_LOAD segment with p_memsz > p_filesz | |
1047 | before this one. Map anonymous pages, if needed, | |
1048 | and clear the area. */ | |
f670d0ec | 1049 | retval = set_brk(elf_bss + load_bias, |
16e72e9b DV |
1050 | elf_brk + load_bias, |
1051 | bss_prot); | |
19d860a1 | 1052 | if (retval) |
1da177e4 | 1053 | goto out_free_dentry; |
1da177e4 LT |
1054 | nbyte = ELF_PAGEOFFSET(elf_bss); |
1055 | if (nbyte) { | |
1056 | nbyte = ELF_MIN_ALIGN - nbyte; | |
1057 | if (nbyte > elf_brk - elf_bss) | |
1058 | nbyte = elf_brk - elf_bss; | |
1059 | if (clear_user((void __user *)elf_bss + | |
1060 | load_bias, nbyte)) { | |
1061 | /* | |
1062 | * This bss-zeroing can fail if the ELF | |
f4e5cc2c | 1063 | * file specifies odd protections. So |
1da177e4 LT |
1064 | * we don't check the return value |
1065 | */ | |
1066 | } | |
1067 | } | |
1068 | } | |
1069 | ||
fe0f6766 DM |
1070 | elf_prot = make_prot(elf_ppnt->p_flags, &arch_state, |
1071 | !!interpreter, false); | |
1da177e4 | 1072 | |
4589ff7c | 1073 | elf_flags = MAP_PRIVATE; |
1da177e4 LT |
1074 | |
1075 | vaddr = elf_ppnt->p_vaddr; | |
eab09532 KC |
1076 | /* |
1077 | * If we are loading ET_EXEC or we have already performed | |
1078 | * the ET_DYN load_addr calculations, proceed normally. | |
1079 | */ | |
a62c5b1b | 1080 | if (elf_ex->e_type == ET_EXEC || load_addr_set) { |
b212921b | 1081 | elf_flags |= MAP_FIXED; |
a62c5b1b | 1082 | } else if (elf_ex->e_type == ET_DYN) { |
eab09532 KC |
1083 | /* |
1084 | * This logic is run once for the first LOAD Program | |
1085 | * Header for ET_DYN binaries to calculate the | |
1086 | * randomization (load_bias) for all the LOAD | |
1087 | * Program Headers, and to calculate the entire | |
1088 | * size of the ELF mapping (total_size). (Note that | |
1089 | * load_addr_set is set to true later once the | |
1090 | * initial mapping is performed.) | |
1091 | * | |
1092 | * There are effectively two types of ET_DYN | |
1093 | * binaries: programs (i.e. PIE: ET_DYN with INTERP) | |
1094 | * and loaders (ET_DYN without INTERP, since they | |
1095 | * _are_ the ELF interpreter). The loaders must | |
1096 | * be loaded away from programs since the program | |
1097 | * may otherwise collide with the loader (especially | |
1098 | * for ET_EXEC which does not have a randomized | |
1099 | * position). For example to handle invocations of | |
1100 | * "./ld.so someprog" to test out a new version of | |
1101 | * the loader, the subsequent program that the | |
1102 | * loader loads must avoid the loader itself, so | |
1103 | * they cannot share the same load range. Sufficient | |
1104 | * room for the brk must be allocated with the | |
1105 | * loader as well, since brk must be available with | |
1106 | * the loader. | |
1107 | * | |
1108 | * Therefore, programs are loaded offset from | |
1109 | * ELF_ET_DYN_BASE and loaders are loaded into the | |
1110 | * independently randomized mmap region (0 load_bias | |
1111 | * without MAP_FIXED). | |
1112 | */ | |
cc338010 | 1113 | if (interpreter) { |
eab09532 KC |
1114 | load_bias = ELF_ET_DYN_BASE; |
1115 | if (current->flags & PF_RANDOMIZE) | |
1116 | load_bias += arch_mmap_rnd(); | |
ce81bb25 CK |
1117 | alignment = maximum_alignment(elf_phdata, elf_ex->e_phnum); |
1118 | if (alignment) | |
1119 | load_bias &= ~(alignment - 1); | |
b212921b | 1120 | elf_flags |= MAP_FIXED; |
eab09532 KC |
1121 | } else |
1122 | load_bias = 0; | |
1123 | ||
1124 | /* | |
1125 | * Since load_bias is used for all subsequent loading | |
1126 | * calculations, we must lower it by the first vaddr | |
1127 | * so that the remaining calculations based on the | |
1128 | * ELF vaddrs will be correctly offset. The result | |
1129 | * is then page aligned. | |
1130 | */ | |
1131 | load_bias = ELF_PAGESTART(load_bias - vaddr); | |
1132 | ||
a87938b2 | 1133 | total_size = total_mapping_size(elf_phdata, |
a62c5b1b | 1134 | elf_ex->e_phnum); |
a87938b2 | 1135 | if (!total_size) { |
2b1d3ae9 | 1136 | retval = -EINVAL; |
a87938b2 MD |
1137 | goto out_free_dentry; |
1138 | } | |
1da177e4 LT |
1139 | } |
1140 | ||
f4e5cc2c | 1141 | error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt, |
a87938b2 | 1142 | elf_prot, elf_flags, total_size); |
1da177e4 | 1143 | if (BAD_ADDR(error)) { |
b140f251 AK |
1144 | retval = IS_ERR((void *)error) ? |
1145 | PTR_ERR((void*)error) : -EINVAL; | |
1da177e4 LT |
1146 | goto out_free_dentry; |
1147 | } | |
1148 | ||
1149 | if (!load_addr_set) { | |
1150 | load_addr_set = 1; | |
1151 | load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset); | |
a62c5b1b | 1152 | if (elf_ex->e_type == ET_DYN) { |
1da177e4 LT |
1153 | load_bias += error - |
1154 | ELF_PAGESTART(load_bias + vaddr); | |
1155 | load_addr += load_bias; | |
1156 | reloc_func_desc = load_bias; | |
1157 | } | |
1158 | } | |
1159 | k = elf_ppnt->p_vaddr; | |
f67ef446 | 1160 | if ((elf_ppnt->p_flags & PF_X) && k < start_code) |
f4e5cc2c JJ |
1161 | start_code = k; |
1162 | if (start_data < k) | |
1163 | start_data = k; | |
1da177e4 LT |
1164 | |
1165 | /* | |
1166 | * Check to see if the section's size will overflow the | |
1167 | * allowed task size. Note that p_filesz must always be | |
1168 | * <= p_memsz so it is only necessary to check p_memsz. | |
1169 | */ | |
ce51059b | 1170 | if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz || |
1da177e4 LT |
1171 | elf_ppnt->p_memsz > TASK_SIZE || |
1172 | TASK_SIZE - elf_ppnt->p_memsz < k) { | |
f4e5cc2c | 1173 | /* set_brk can never work. Avoid overflows. */ |
b140f251 | 1174 | retval = -EINVAL; |
1da177e4 LT |
1175 | goto out_free_dentry; |
1176 | } | |
1177 | ||
1178 | k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz; | |
1179 | ||
1180 | if (k > elf_bss) | |
1181 | elf_bss = k; | |
1182 | if ((elf_ppnt->p_flags & PF_X) && end_code < k) | |
1183 | end_code = k; | |
1184 | if (end_data < k) | |
1185 | end_data = k; | |
1186 | k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz; | |
16e72e9b DV |
1187 | if (k > elf_brk) { |
1188 | bss_prot = elf_prot; | |
1da177e4 | 1189 | elf_brk = k; |
16e72e9b | 1190 | } |
1da177e4 LT |
1191 | } |
1192 | ||
a62c5b1b | 1193 | e_entry = elf_ex->e_entry + load_bias; |
1da177e4 LT |
1194 | elf_bss += load_bias; |
1195 | elf_brk += load_bias; | |
1196 | start_code += load_bias; | |
1197 | end_code += load_bias; | |
1198 | start_data += load_bias; | |
1199 | end_data += load_bias; | |
1200 | ||
1201 | /* Calling set_brk effectively mmaps the pages that we need | |
1202 | * for the bss and break sections. We must do this before | |
1203 | * mapping in the interpreter, to make sure it doesn't wind | |
1204 | * up getting placed where the bss needs to go. | |
1205 | */ | |
16e72e9b | 1206 | retval = set_brk(elf_bss, elf_brk, bss_prot); |
19d860a1 | 1207 | if (retval) |
1da177e4 | 1208 | goto out_free_dentry; |
6de50517 | 1209 | if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) { |
1da177e4 LT |
1210 | retval = -EFAULT; /* Nobody gets to see this, but.. */ |
1211 | goto out_free_dentry; | |
1212 | } | |
1213 | ||
cc338010 | 1214 | if (interpreter) { |
c69bcc93 | 1215 | elf_entry = load_elf_interp(interp_elf_ex, |
d20894a2 | 1216 | interpreter, |
fe0f6766 DM |
1217 | load_bias, interp_elf_phdata, |
1218 | &arch_state); | |
d20894a2 AK |
1219 | if (!IS_ERR((void *)elf_entry)) { |
1220 | /* | |
1221 | * load_elf_interp() returns relocation | |
1222 | * adjustment | |
1223 | */ | |
1224 | interp_load_addr = elf_entry; | |
c69bcc93 | 1225 | elf_entry += interp_elf_ex->e_entry; |
cc503c1b | 1226 | } |
1da177e4 | 1227 | if (BAD_ADDR(elf_entry)) { |
ce51059b CE |
1228 | retval = IS_ERR((void *)elf_entry) ? |
1229 | (int)elf_entry : -EINVAL; | |
1da177e4 LT |
1230 | goto out_free_dentry; |
1231 | } | |
1232 | reloc_func_desc = interp_load_addr; | |
1233 | ||
1234 | allow_write_access(interpreter); | |
1235 | fput(interpreter); | |
0693ffeb AD |
1236 | |
1237 | kfree(interp_elf_ex); | |
aa0d1564 | 1238 | kfree(interp_elf_phdata); |
1da177e4 | 1239 | } else { |
a62c5b1b | 1240 | elf_entry = e_entry; |
5342fba5 | 1241 | if (BAD_ADDR(elf_entry)) { |
ce51059b | 1242 | retval = -EINVAL; |
5342fba5 SS |
1243 | goto out_free_dentry; |
1244 | } | |
1da177e4 LT |
1245 | } |
1246 | ||
1247 | kfree(elf_phdata); | |
1248 | ||
1da177e4 LT |
1249 | set_binfmt(&elf_format); |
1250 | ||
547ee84c | 1251 | #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES |
9a29a671 | 1252 | retval = ARCH_SETUP_ADDITIONAL_PAGES(bprm, elf_ex, !!interpreter); |
19d860a1 | 1253 | if (retval < 0) |
18c8baff | 1254 | goto out; |
547ee84c BH |
1255 | #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */ |
1256 | ||
a62c5b1b AD |
1257 | retval = create_elf_tables(bprm, elf_ex, |
1258 | load_addr, interp_load_addr, e_entry); | |
19d860a1 | 1259 | if (retval < 0) |
b6a2fea3 | 1260 | goto out; |
03c6d723 AD |
1261 | |
1262 | mm = current->mm; | |
1263 | mm->end_code = end_code; | |
1264 | mm->start_code = start_code; | |
1265 | mm->start_data = start_data; | |
1266 | mm->end_data = end_data; | |
1267 | mm->start_stack = bprm->p; | |
1da177e4 | 1268 | |
4471a675 | 1269 | if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) { |
bbdc6076 KC |
1270 | /* |
1271 | * For architectures with ELF randomization, when executing | |
1272 | * a loader directly (i.e. no interpreter listed in ELF | |
1273 | * headers), move the brk area out of the mmap region | |
1274 | * (since it grows up, and may collide early with the stack | |
1275 | * growing down), and into the unused ELF_ET_DYN_BASE region. | |
1276 | */ | |
7be3cb01 | 1277 | if (IS_ENABLED(CONFIG_ARCH_HAS_ELF_RANDOMIZE) && |
03c6d723 AD |
1278 | elf_ex->e_type == ET_DYN && !interpreter) { |
1279 | mm->brk = mm->start_brk = ELF_ET_DYN_BASE; | |
1280 | } | |
bbdc6076 | 1281 | |
03c6d723 | 1282 | mm->brk = mm->start_brk = arch_randomize_brk(mm); |
204db6ed | 1283 | #ifdef compat_brk_randomized |
4471a675 JK |
1284 | current->brk_randomized = 1; |
1285 | #endif | |
1286 | } | |
c1d171a0 | 1287 | |
1da177e4 LT |
1288 | if (current->personality & MMAP_PAGE_ZERO) { |
1289 | /* Why this, you ask??? Well SVr4 maps page 0 as read-only, | |
1290 | and some applications "depend" upon this behavior. | |
1291 | Since we do not have the power to recompile these, we | |
f4e5cc2c | 1292 | emulate the SVr4 behavior. Sigh. */ |
6be5ceb0 | 1293 | error = vm_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC, |
1da177e4 | 1294 | MAP_FIXED | MAP_PRIVATE, 0); |
1da177e4 LT |
1295 | } |
1296 | ||
249b08e4 | 1297 | regs = current_pt_regs(); |
1da177e4 LT |
1298 | #ifdef ELF_PLAT_INIT |
1299 | /* | |
1300 | * The ABI may specify that certain registers be set up in special | |
1301 | * ways (on i386 %edx is the address of a DT_FINI function, for | |
1302 | * example. In addition, it may also specify (eg, PowerPC64 ELF) | |
1303 | * that the e_entry field is the address of the function descriptor | |
1304 | * for the startup routine, rather than the address of the startup | |
1305 | * routine itself. This macro performs whatever initialization to | |
1306 | * the regs structure is required as well as any relocations to the | |
1307 | * function descriptor entries when executing dynamically links apps. | |
1308 | */ | |
1309 | ELF_PLAT_INIT(regs, reloc_func_desc); | |
1310 | #endif | |
1311 | ||
b8383831 | 1312 | finalize_exec(bprm); |
bc3d7bf6 | 1313 | START_THREAD(elf_ex, regs, elf_entry, bprm->p); |
1da177e4 LT |
1314 | retval = 0; |
1315 | out: | |
1da177e4 LT |
1316 | return retval; |
1317 | ||
1318 | /* error cleanup */ | |
1319 | out_free_dentry: | |
0693ffeb | 1320 | kfree(interp_elf_ex); |
a9d9ef13 | 1321 | kfree(interp_elf_phdata); |
1da177e4 LT |
1322 | allow_write_access(interpreter); |
1323 | if (interpreter) | |
1324 | fput(interpreter); | |
1da177e4 LT |
1325 | out_free_ph: |
1326 | kfree(elf_phdata); | |
1327 | goto out; | |
1328 | } | |
1329 | ||
69369a70 | 1330 | #ifdef CONFIG_USELIB |
1da177e4 LT |
1331 | /* This is really simpleminded and specialized - we are loading an |
1332 | a.out library that is given an ELF header. */ | |
1da177e4 LT |
1333 | static int load_elf_library(struct file *file) |
1334 | { | |
1335 | struct elf_phdr *elf_phdata; | |
1336 | struct elf_phdr *eppnt; | |
1337 | unsigned long elf_bss, bss, len; | |
1338 | int retval, error, i, j; | |
1339 | struct elfhdr elf_ex; | |
1340 | ||
1341 | error = -ENOEXEC; | |
658c0335 AD |
1342 | retval = elf_read(file, &elf_ex, sizeof(elf_ex), 0); |
1343 | if (retval < 0) | |
1da177e4 LT |
1344 | goto out; |
1345 | ||
1346 | if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0) | |
1347 | goto out; | |
1348 | ||
1349 | /* First of all, some simple consistency checks */ | |
1350 | if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 || | |
72c2d531 | 1351 | !elf_check_arch(&elf_ex) || !file->f_op->mmap) |
1da177e4 | 1352 | goto out; |
4755200b NP |
1353 | if (elf_check_fdpic(&elf_ex)) |
1354 | goto out; | |
1da177e4 LT |
1355 | |
1356 | /* Now read in all of the header information */ | |
1357 | ||
1358 | j = sizeof(struct elf_phdr) * elf_ex.e_phnum; | |
1359 | /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */ | |
1360 | ||
1361 | error = -ENOMEM; | |
1362 | elf_phdata = kmalloc(j, GFP_KERNEL); | |
1363 | if (!elf_phdata) | |
1364 | goto out; | |
1365 | ||
1366 | eppnt = elf_phdata; | |
1367 | error = -ENOEXEC; | |
658c0335 AD |
1368 | retval = elf_read(file, eppnt, j, elf_ex.e_phoff); |
1369 | if (retval < 0) | |
1da177e4 LT |
1370 | goto out_free_ph; |
1371 | ||
1372 | for (j = 0, i = 0; i<elf_ex.e_phnum; i++) | |
1373 | if ((eppnt + i)->p_type == PT_LOAD) | |
1374 | j++; | |
1375 | if (j != 1) | |
1376 | goto out_free_ph; | |
1377 | ||
1378 | while (eppnt->p_type != PT_LOAD) | |
1379 | eppnt++; | |
1380 | ||
1381 | /* Now use mmap to map the library into memory. */ | |
6be5ceb0 | 1382 | error = vm_mmap(file, |
1da177e4 LT |
1383 | ELF_PAGESTART(eppnt->p_vaddr), |
1384 | (eppnt->p_filesz + | |
1385 | ELF_PAGEOFFSET(eppnt->p_vaddr)), | |
1386 | PROT_READ | PROT_WRITE | PROT_EXEC, | |
42be8b42 | 1387 | MAP_FIXED_NOREPLACE | MAP_PRIVATE, |
1da177e4 LT |
1388 | (eppnt->p_offset - |
1389 | ELF_PAGEOFFSET(eppnt->p_vaddr))); | |
1da177e4 LT |
1390 | if (error != ELF_PAGESTART(eppnt->p_vaddr)) |
1391 | goto out_free_ph; | |
1392 | ||
1393 | elf_bss = eppnt->p_vaddr + eppnt->p_filesz; | |
1394 | if (padzero(elf_bss)) { | |
1395 | error = -EFAULT; | |
1396 | goto out_free_ph; | |
1397 | } | |
1398 | ||
24962af7 OS |
1399 | len = ELF_PAGEALIGN(eppnt->p_filesz + eppnt->p_vaddr); |
1400 | bss = ELF_PAGEALIGN(eppnt->p_memsz + eppnt->p_vaddr); | |
ecc2bc8a MH |
1401 | if (bss > len) { |
1402 | error = vm_brk(len, bss - len); | |
5d22fc25 | 1403 | if (error) |
ecc2bc8a MH |
1404 | goto out_free_ph; |
1405 | } | |
1da177e4 LT |
1406 | error = 0; |
1407 | ||
1408 | out_free_ph: | |
1409 | kfree(elf_phdata); | |
1410 | out: | |
1411 | return error; | |
1412 | } | |
69369a70 | 1413 | #endif /* #ifdef CONFIG_USELIB */ |
1da177e4 | 1414 | |
698ba7b5 | 1415 | #ifdef CONFIG_ELF_CORE |
1da177e4 LT |
1416 | /* |
1417 | * ELF core dumper | |
1418 | * | |
1419 | * Modelled on fs/exec.c:aout_core_dump() | |
1420 | * Jeremy Fitzhardinge <jeremy@sw.oz.au> | |
1421 | */ | |
1da177e4 | 1422 | |
1da177e4 LT |
1423 | /* An ELF note in memory */ |
1424 | struct memelfnote | |
1425 | { | |
1426 | const char *name; | |
1427 | int type; | |
1428 | unsigned int datasz; | |
1429 | void *data; | |
1430 | }; | |
1431 | ||
1432 | static int notesize(struct memelfnote *en) | |
1433 | { | |
1434 | int sz; | |
1435 | ||
1436 | sz = sizeof(struct elf_note); | |
1437 | sz += roundup(strlen(en->name) + 1, 4); | |
1438 | sz += roundup(en->datasz, 4); | |
1439 | ||
1440 | return sz; | |
1441 | } | |
1442 | ||
ecc8c772 | 1443 | static int writenote(struct memelfnote *men, struct coredump_params *cprm) |
d025c9db AK |
1444 | { |
1445 | struct elf_note en; | |
1da177e4 LT |
1446 | en.n_namesz = strlen(men->name) + 1; |
1447 | en.n_descsz = men->datasz; | |
1448 | en.n_type = men->type; | |
1449 | ||
ecc8c772 | 1450 | return dump_emit(cprm, &en, sizeof(en)) && |
22a8cb82 AV |
1451 | dump_emit(cprm, men->name, en.n_namesz) && dump_align(cprm, 4) && |
1452 | dump_emit(cprm, men->data, men->datasz) && dump_align(cprm, 4); | |
1da177e4 | 1453 | } |
1da177e4 | 1454 | |
3aba481f | 1455 | static void fill_elf_header(struct elfhdr *elf, int segs, |
d3330cf0 | 1456 | u16 machine, u32 flags) |
1da177e4 | 1457 | { |
6970c8ef CG |
1458 | memset(elf, 0, sizeof(*elf)); |
1459 | ||
1da177e4 LT |
1460 | memcpy(elf->e_ident, ELFMAG, SELFMAG); |
1461 | elf->e_ident[EI_CLASS] = ELF_CLASS; | |
1462 | elf->e_ident[EI_DATA] = ELF_DATA; | |
1463 | elf->e_ident[EI_VERSION] = EV_CURRENT; | |
1464 | elf->e_ident[EI_OSABI] = ELF_OSABI; | |
1da177e4 LT |
1465 | |
1466 | elf->e_type = ET_CORE; | |
3aba481f | 1467 | elf->e_machine = machine; |
1da177e4 | 1468 | elf->e_version = EV_CURRENT; |
1da177e4 | 1469 | elf->e_phoff = sizeof(struct elfhdr); |
3aba481f | 1470 | elf->e_flags = flags; |
1da177e4 LT |
1471 | elf->e_ehsize = sizeof(struct elfhdr); |
1472 | elf->e_phentsize = sizeof(struct elf_phdr); | |
1473 | elf->e_phnum = segs; | |
1da177e4 LT |
1474 | } |
1475 | ||
8d6b5eee | 1476 | static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset) |
1da177e4 LT |
1477 | { |
1478 | phdr->p_type = PT_NOTE; | |
1479 | phdr->p_offset = offset; | |
1480 | phdr->p_vaddr = 0; | |
1481 | phdr->p_paddr = 0; | |
1482 | phdr->p_filesz = sz; | |
1483 | phdr->p_memsz = 0; | |
1484 | phdr->p_flags = 0; | |
1485 | phdr->p_align = 0; | |
1da177e4 LT |
1486 | } |
1487 | ||
1488 | static void fill_note(struct memelfnote *note, const char *name, int type, | |
1489 | unsigned int sz, void *data) | |
1490 | { | |
1491 | note->name = name; | |
1492 | note->type = type; | |
1493 | note->datasz = sz; | |
1494 | note->data = data; | |
1da177e4 LT |
1495 | } |
1496 | ||
1497 | /* | |
f4e5cc2c JJ |
1498 | * fill up all the fields in prstatus from the given task struct, except |
1499 | * registers which need to be filled up separately. | |
1da177e4 | 1500 | */ |
f2485a2d | 1501 | static void fill_prstatus(struct elf_prstatus_common *prstatus, |
f4e5cc2c | 1502 | struct task_struct *p, long signr) |
1da177e4 LT |
1503 | { |
1504 | prstatus->pr_info.si_signo = prstatus->pr_cursig = signr; | |
1505 | prstatus->pr_sigpend = p->pending.signal.sig[0]; | |
1506 | prstatus->pr_sighold = p->blocked.sig[0]; | |
3b34fc58 ON |
1507 | rcu_read_lock(); |
1508 | prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent)); | |
1509 | rcu_read_unlock(); | |
b488893a | 1510 | prstatus->pr_pid = task_pid_vnr(p); |
b488893a PE |
1511 | prstatus->pr_pgrp = task_pgrp_vnr(p); |
1512 | prstatus->pr_sid = task_session_vnr(p); | |
1da177e4 | 1513 | if (thread_group_leader(p)) { |
cd19c364 | 1514 | struct task_cputime cputime; |
f06febc9 | 1515 | |
1da177e4 | 1516 | /* |
f06febc9 FM |
1517 | * This is the record for the group leader. It shows the |
1518 | * group-wide total, not its individual thread total. | |
1da177e4 | 1519 | */ |
cd19c364 | 1520 | thread_group_cputime(p, &cputime); |
e2bb80d5 AB |
1521 | prstatus->pr_utime = ns_to_kernel_old_timeval(cputime.utime); |
1522 | prstatus->pr_stime = ns_to_kernel_old_timeval(cputime.stime); | |
1da177e4 | 1523 | } else { |
cd19c364 | 1524 | u64 utime, stime; |
6fac4829 | 1525 | |
cd19c364 | 1526 | task_cputime(p, &utime, &stime); |
e2bb80d5 AB |
1527 | prstatus->pr_utime = ns_to_kernel_old_timeval(utime); |
1528 | prstatus->pr_stime = ns_to_kernel_old_timeval(stime); | |
1da177e4 | 1529 | } |
5613fda9 | 1530 | |
e2bb80d5 AB |
1531 | prstatus->pr_cutime = ns_to_kernel_old_timeval(p->signal->cutime); |
1532 | prstatus->pr_cstime = ns_to_kernel_old_timeval(p->signal->cstime); | |
1da177e4 LT |
1533 | } |
1534 | ||
1535 | static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p, | |
1536 | struct mm_struct *mm) | |
1537 | { | |
c69e8d9c | 1538 | const struct cred *cred; |
a84a5059 | 1539 | unsigned int i, len; |
2f064a59 PZ |
1540 | unsigned int state; |
1541 | ||
1da177e4 LT |
1542 | /* first copy the parameters from user space */ |
1543 | memset(psinfo, 0, sizeof(struct elf_prpsinfo)); | |
1544 | ||
1545 | len = mm->arg_end - mm->arg_start; | |
1546 | if (len >= ELF_PRARGSZ) | |
1547 | len = ELF_PRARGSZ-1; | |
1548 | if (copy_from_user(&psinfo->pr_psargs, | |
1549 | (const char __user *)mm->arg_start, len)) | |
1550 | return -EFAULT; | |
1551 | for(i = 0; i < len; i++) | |
1552 | if (psinfo->pr_psargs[i] == 0) | |
1553 | psinfo->pr_psargs[i] = ' '; | |
1554 | psinfo->pr_psargs[len] = 0; | |
1555 | ||
3b34fc58 ON |
1556 | rcu_read_lock(); |
1557 | psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent)); | |
1558 | rcu_read_unlock(); | |
b488893a | 1559 | psinfo->pr_pid = task_pid_vnr(p); |
b488893a PE |
1560 | psinfo->pr_pgrp = task_pgrp_vnr(p); |
1561 | psinfo->pr_sid = task_session_vnr(p); | |
1da177e4 | 1562 | |
2f064a59 PZ |
1563 | state = READ_ONCE(p->__state); |
1564 | i = state ? ffz(~state) + 1 : 0; | |
1da177e4 | 1565 | psinfo->pr_state = i; |
55148548 | 1566 | psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i]; |
1da177e4 LT |
1567 | psinfo->pr_zomb = psinfo->pr_sname == 'Z'; |
1568 | psinfo->pr_nice = task_nice(p); | |
1569 | psinfo->pr_flag = p->flags; | |
c69e8d9c DH |
1570 | rcu_read_lock(); |
1571 | cred = __task_cred(p); | |
ebc887b2 EB |
1572 | SET_UID(psinfo->pr_uid, from_kuid_munged(cred->user_ns, cred->uid)); |
1573 | SET_GID(psinfo->pr_gid, from_kgid_munged(cred->user_ns, cred->gid)); | |
c69e8d9c | 1574 | rcu_read_unlock(); |
1da177e4 | 1575 | strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname)); |
2f064a59 | 1576 | |
1da177e4 LT |
1577 | return 0; |
1578 | } | |
1579 | ||
3aba481f RM |
1580 | static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm) |
1581 | { | |
1582 | elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv; | |
1583 | int i = 0; | |
1584 | do | |
1585 | i += 2; | |
1586 | while (auxv[i - 2] != AT_NULL); | |
1587 | fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv); | |
1588 | } | |
1589 | ||
49ae4d4b | 1590 | static void fill_siginfo_note(struct memelfnote *note, user_siginfo_t *csigdata, |
ae7795bc | 1591 | const kernel_siginfo_t *siginfo) |
49ae4d4b | 1592 | { |
fa4751f4 | 1593 | copy_siginfo_to_external(csigdata, siginfo); |
49ae4d4b DV |
1594 | fill_note(note, "CORE", NT_SIGINFO, sizeof(*csigdata), csigdata); |
1595 | } | |
1596 | ||
2aa362c4 DV |
1597 | #define MAX_FILE_NOTE_SIZE (4*1024*1024) |
1598 | /* | |
1599 | * Format of NT_FILE note: | |
1600 | * | |
1601 | * long count -- how many files are mapped | |
1602 | * long page_size -- units for file_ofs | |
1603 | * array of [COUNT] elements of | |
1604 | * long start | |
1605 | * long end | |
1606 | * long file_ofs | |
1607 | * followed by COUNT filenames in ASCII: "FILE1" NUL "FILE2" NUL... | |
1608 | */ | |
72023656 | 1609 | static int fill_files_note(struct memelfnote *note) |
2aa362c4 | 1610 | { |
03c6d723 | 1611 | struct mm_struct *mm = current->mm; |
2aa362c4 DV |
1612 | struct vm_area_struct *vma; |
1613 | unsigned count, size, names_ofs, remaining, n; | |
1614 | user_long_t *data; | |
1615 | user_long_t *start_end_ofs; | |
1616 | char *name_base, *name_curpos; | |
1617 | ||
1618 | /* *Estimated* file count and total data size needed */ | |
03c6d723 | 1619 | count = mm->map_count; |
60c9d92f AD |
1620 | if (count > UINT_MAX / 64) |
1621 | return -EINVAL; | |
2aa362c4 DV |
1622 | size = count * 64; |
1623 | ||
1624 | names_ofs = (2 + 3 * count) * sizeof(data[0]); | |
1625 | alloc: | |
1626 | if (size >= MAX_FILE_NOTE_SIZE) /* paranoia check */ | |
72023656 | 1627 | return -EINVAL; |
2aa362c4 | 1628 | size = round_up(size, PAGE_SIZE); |
1fbede6e AD |
1629 | /* |
1630 | * "size" can be 0 here legitimately. | |
1631 | * Let it ENOMEM and omit NT_FILE section which will be empty anyway. | |
1632 | */ | |
86a2bb5a AD |
1633 | data = kvmalloc(size, GFP_KERNEL); |
1634 | if (ZERO_OR_NULL_PTR(data)) | |
72023656 | 1635 | return -ENOMEM; |
2aa362c4 DV |
1636 | |
1637 | start_end_ofs = data + 2; | |
1638 | name_base = name_curpos = ((char *)data) + names_ofs; | |
1639 | remaining = size - names_ofs; | |
1640 | count = 0; | |
03c6d723 | 1641 | for (vma = mm->mmap; vma != NULL; vma = vma->vm_next) { |
2aa362c4 DV |
1642 | struct file *file; |
1643 | const char *filename; | |
1644 | ||
1645 | file = vma->vm_file; | |
1646 | if (!file) | |
1647 | continue; | |
9bf39ab2 | 1648 | filename = file_path(file, name_curpos, remaining); |
2aa362c4 DV |
1649 | if (IS_ERR(filename)) { |
1650 | if (PTR_ERR(filename) == -ENAMETOOLONG) { | |
86a2bb5a | 1651 | kvfree(data); |
2aa362c4 DV |
1652 | size = size * 5 / 4; |
1653 | goto alloc; | |
1654 | } | |
1655 | continue; | |
1656 | } | |
1657 | ||
9bf39ab2 | 1658 | /* file_path() fills at the end, move name down */ |
2aa362c4 DV |
1659 | /* n = strlen(filename) + 1: */ |
1660 | n = (name_curpos + remaining) - filename; | |
1661 | remaining = filename - name_curpos; | |
1662 | memmove(name_curpos, filename, n); | |
1663 | name_curpos += n; | |
1664 | ||
1665 | *start_end_ofs++ = vma->vm_start; | |
1666 | *start_end_ofs++ = vma->vm_end; | |
1667 | *start_end_ofs++ = vma->vm_pgoff; | |
1668 | count++; | |
1669 | } | |
1670 | ||
1671 | /* Now we know exact count of files, can store it */ | |
1672 | data[0] = count; | |
1673 | data[1] = PAGE_SIZE; | |
1674 | /* | |
03c6d723 | 1675 | * Count usually is less than mm->map_count, |
2aa362c4 DV |
1676 | * we need to move filenames down. |
1677 | */ | |
03c6d723 | 1678 | n = mm->map_count - count; |
2aa362c4 DV |
1679 | if (n != 0) { |
1680 | unsigned shift_bytes = n * 3 * sizeof(data[0]); | |
1681 | memmove(name_base - shift_bytes, name_base, | |
1682 | name_curpos - name_base); | |
1683 | name_curpos -= shift_bytes; | |
1684 | } | |
1685 | ||
1686 | size = name_curpos - (char *)data; | |
1687 | fill_note(note, "CORE", NT_FILE, size, data); | |
72023656 | 1688 | return 0; |
2aa362c4 DV |
1689 | } |
1690 | ||
4206d3aa RM |
1691 | #ifdef CORE_DUMP_USE_REGSET |
1692 | #include <linux/regset.h> | |
1693 | ||
1694 | struct elf_thread_core_info { | |
1695 | struct elf_thread_core_info *next; | |
1696 | struct task_struct *task; | |
1697 | struct elf_prstatus prstatus; | |
5e01fdff | 1698 | struct memelfnote notes[]; |
4206d3aa RM |
1699 | }; |
1700 | ||
1701 | struct elf_note_info { | |
1702 | struct elf_thread_core_info *thread; | |
1703 | struct memelfnote psinfo; | |
49ae4d4b | 1704 | struct memelfnote signote; |
4206d3aa | 1705 | struct memelfnote auxv; |
2aa362c4 | 1706 | struct memelfnote files; |
49ae4d4b | 1707 | user_siginfo_t csigdata; |
4206d3aa RM |
1708 | size_t size; |
1709 | int thread_notes; | |
1710 | }; | |
1711 | ||
d31472b6 RM |
1712 | /* |
1713 | * When a regset has a writeback hook, we call it on each thread before | |
1714 | * dumping user memory. On register window machines, this makes sure the | |
1715 | * user memory backing the register data is up to date before we read it. | |
1716 | */ | |
1717 | static void do_thread_regset_writeback(struct task_struct *task, | |
1718 | const struct user_regset *regset) | |
1719 | { | |
1720 | if (regset->writeback) | |
1721 | regset->writeback(task, regset, 1); | |
1722 | } | |
1723 | ||
0953f65d | 1724 | #ifndef PRSTATUS_SIZE |
8a00dd00 | 1725 | #define PRSTATUS_SIZE sizeof(struct elf_prstatus) |
0953f65d L |
1726 | #endif |
1727 | ||
1728 | #ifndef SET_PR_FPVALID | |
8a00dd00 | 1729 | #define SET_PR_FPVALID(S) ((S)->pr_fpvalid = 1) |
0953f65d L |
1730 | #endif |
1731 | ||
4206d3aa RM |
1732 | static int fill_thread_core_info(struct elf_thread_core_info *t, |
1733 | const struct user_regset_view *view, | |
1734 | long signr, size_t *total) | |
1735 | { | |
1736 | unsigned int i; | |
1737 | ||
1738 | /* | |
1739 | * NT_PRSTATUS is the one special case, because the regset data | |
1740 | * goes into the pr_reg field inside the note contents, rather | |
1741 | * than being the whole note contents. We fill the reset in here. | |
1742 | * We assume that regset 0 is NT_PRSTATUS. | |
1743 | */ | |
f2485a2d | 1744 | fill_prstatus(&t->prstatus.common, t->task, signr); |
8a00dd00 | 1745 | regset_get(t->task, &view->regsets[0], |
b4e9c954 | 1746 | sizeof(t->prstatus.pr_reg), &t->prstatus.pr_reg); |
4206d3aa RM |
1747 | |
1748 | fill_note(&t->notes[0], "CORE", NT_PRSTATUS, | |
8a00dd00 | 1749 | PRSTATUS_SIZE, &t->prstatus); |
4206d3aa RM |
1750 | *total += notesize(&t->notes[0]); |
1751 | ||
d31472b6 RM |
1752 | do_thread_regset_writeback(t->task, &view->regsets[0]); |
1753 | ||
4206d3aa RM |
1754 | /* |
1755 | * Each other regset might generate a note too. For each regset | |
1756 | * that has no core_note_type or is inactive, we leave t->notes[i] | |
1757 | * all zero and we'll know to skip writing it later. | |
1758 | */ | |
1759 | for (i = 1; i < view->n; ++i) { | |
1760 | const struct user_regset *regset = &view->regsets[i]; | |
b4e9c954 AV |
1761 | int note_type = regset->core_note_type; |
1762 | bool is_fpreg = note_type == NT_PRFPREG; | |
1763 | void *data; | |
1764 | int ret; | |
1765 | ||
d31472b6 | 1766 | do_thread_regset_writeback(t->task, regset); |
b4e9c954 AV |
1767 | if (!note_type) // not for coredumps |
1768 | continue; | |
1769 | if (regset->active && regset->active(t->task, regset) <= 0) | |
1770 | continue; | |
1771 | ||
1772 | ret = regset_get_alloc(t->task, regset, ~0U, &data); | |
1773 | if (ret < 0) | |
1774 | continue; | |
1775 | ||
1776 | if (is_fpreg) | |
8a00dd00 | 1777 | SET_PR_FPVALID(&t->prstatus); |
b4e9c954 AV |
1778 | |
1779 | fill_note(&t->notes[i], is_fpreg ? "CORE" : "LINUX", | |
1780 | note_type, ret, data); | |
1781 | ||
1782 | *total += notesize(&t->notes[i]); | |
4206d3aa RM |
1783 | } |
1784 | ||
1785 | return 1; | |
1786 | } | |
1787 | ||
1788 | static int fill_note_info(struct elfhdr *elf, int phdrs, | |
1789 | struct elf_note_info *info, | |
ae7795bc | 1790 | const kernel_siginfo_t *siginfo, struct pt_regs *regs) |
4206d3aa RM |
1791 | { |
1792 | struct task_struct *dump_task = current; | |
1793 | const struct user_regset_view *view = task_user_regset_view(dump_task); | |
1794 | struct elf_thread_core_info *t; | |
1795 | struct elf_prpsinfo *psinfo; | |
83914441 | 1796 | struct core_thread *ct; |
4206d3aa RM |
1797 | unsigned int i; |
1798 | ||
1799 | info->size = 0; | |
1800 | info->thread = NULL; | |
1801 | ||
1802 | psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL); | |
6899e92d AC |
1803 | if (psinfo == NULL) { |
1804 | info->psinfo.data = NULL; /* So we don't free this wrongly */ | |
4206d3aa | 1805 | return 0; |
6899e92d | 1806 | } |
4206d3aa | 1807 | |
e2dbe125 AW |
1808 | fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo); |
1809 | ||
4206d3aa RM |
1810 | /* |
1811 | * Figure out how many notes we're going to need for each thread. | |
1812 | */ | |
1813 | info->thread_notes = 0; | |
1814 | for (i = 0; i < view->n; ++i) | |
1815 | if (view->regsets[i].core_note_type != 0) | |
1816 | ++info->thread_notes; | |
1817 | ||
1818 | /* | |
1819 | * Sanity check. We rely on regset 0 being in NT_PRSTATUS, | |
1820 | * since it is our one special case. | |
1821 | */ | |
1822 | if (unlikely(info->thread_notes == 0) || | |
1823 | unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) { | |
1824 | WARN_ON(1); | |
1825 | return 0; | |
1826 | } | |
1827 | ||
1828 | /* | |
1829 | * Initialize the ELF file header. | |
1830 | */ | |
1831 | fill_elf_header(elf, phdrs, | |
d3330cf0 | 1832 | view->e_machine, view->e_flags); |
4206d3aa RM |
1833 | |
1834 | /* | |
1835 | * Allocate a structure for each thread. | |
1836 | */ | |
83914441 ON |
1837 | for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) { |
1838 | t = kzalloc(offsetof(struct elf_thread_core_info, | |
1839 | notes[info->thread_notes]), | |
1840 | GFP_KERNEL); | |
1841 | if (unlikely(!t)) | |
1842 | return 0; | |
1843 | ||
1844 | t->task = ct->task; | |
1845 | if (ct->task == dump_task || !info->thread) { | |
1846 | t->next = info->thread; | |
1847 | info->thread = t; | |
1848 | } else { | |
1849 | /* | |
1850 | * Make sure to keep the original task at | |
1851 | * the head of the list. | |
1852 | */ | |
1853 | t->next = info->thread->next; | |
1854 | info->thread->next = t; | |
4206d3aa | 1855 | } |
83914441 | 1856 | } |
4206d3aa RM |
1857 | |
1858 | /* | |
1859 | * Now fill in each thread's information. | |
1860 | */ | |
1861 | for (t = info->thread; t != NULL; t = t->next) | |
5ab1c309 | 1862 | if (!fill_thread_core_info(t, view, siginfo->si_signo, &info->size)) |
4206d3aa RM |
1863 | return 0; |
1864 | ||
1865 | /* | |
1866 | * Fill in the two process-wide notes. | |
1867 | */ | |
1868 | fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm); | |
1869 | info->size += notesize(&info->psinfo); | |
1870 | ||
49ae4d4b DV |
1871 | fill_siginfo_note(&info->signote, &info->csigdata, siginfo); |
1872 | info->size += notesize(&info->signote); | |
1873 | ||
4206d3aa RM |
1874 | fill_auxv_note(&info->auxv, current->mm); |
1875 | info->size += notesize(&info->auxv); | |
1876 | ||
72023656 DA |
1877 | if (fill_files_note(&info->files) == 0) |
1878 | info->size += notesize(&info->files); | |
2aa362c4 | 1879 | |
4206d3aa RM |
1880 | return 1; |
1881 | } | |
1882 | ||
1883 | static size_t get_note_info_size(struct elf_note_info *info) | |
1884 | { | |
1885 | return info->size; | |
1886 | } | |
1887 | ||
1888 | /* | |
1889 | * Write all the notes for each thread. When writing the first thread, the | |
1890 | * process-wide notes are interleaved after the first thread-specific note. | |
1891 | */ | |
1892 | static int write_note_info(struct elf_note_info *info, | |
ecc8c772 | 1893 | struct coredump_params *cprm) |
4206d3aa | 1894 | { |
b219e25f | 1895 | bool first = true; |
4206d3aa RM |
1896 | struct elf_thread_core_info *t = info->thread; |
1897 | ||
1898 | do { | |
1899 | int i; | |
1900 | ||
ecc8c772 | 1901 | if (!writenote(&t->notes[0], cprm)) |
4206d3aa RM |
1902 | return 0; |
1903 | ||
ecc8c772 | 1904 | if (first && !writenote(&info->psinfo, cprm)) |
4206d3aa | 1905 | return 0; |
ecc8c772 | 1906 | if (first && !writenote(&info->signote, cprm)) |
49ae4d4b | 1907 | return 0; |
ecc8c772 | 1908 | if (first && !writenote(&info->auxv, cprm)) |
4206d3aa | 1909 | return 0; |
72023656 | 1910 | if (first && info->files.data && |
ecc8c772 | 1911 | !writenote(&info->files, cprm)) |
2aa362c4 | 1912 | return 0; |
4206d3aa RM |
1913 | |
1914 | for (i = 1; i < info->thread_notes; ++i) | |
1915 | if (t->notes[i].data && | |
ecc8c772 | 1916 | !writenote(&t->notes[i], cprm)) |
4206d3aa RM |
1917 | return 0; |
1918 | ||
b219e25f | 1919 | first = false; |
4206d3aa RM |
1920 | t = t->next; |
1921 | } while (t); | |
1922 | ||
1923 | return 1; | |
1924 | } | |
1925 | ||
1926 | static void free_note_info(struct elf_note_info *info) | |
1927 | { | |
1928 | struct elf_thread_core_info *threads = info->thread; | |
1929 | while (threads) { | |
1930 | unsigned int i; | |
1931 | struct elf_thread_core_info *t = threads; | |
1932 | threads = t->next; | |
1933 | WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus); | |
1934 | for (i = 1; i < info->thread_notes; ++i) | |
1935 | kfree(t->notes[i].data); | |
1936 | kfree(t); | |
1937 | } | |
1938 | kfree(info->psinfo.data); | |
86a2bb5a | 1939 | kvfree(info->files.data); |
4206d3aa RM |
1940 | } |
1941 | ||
1942 | #else | |
1943 | ||
1da177e4 LT |
1944 | /* Here is the structure in which status of each thread is captured. */ |
1945 | struct elf_thread_status | |
1946 | { | |
1947 | struct list_head list; | |
1948 | struct elf_prstatus prstatus; /* NT_PRSTATUS */ | |
1949 | elf_fpregset_t fpu; /* NT_PRFPREG */ | |
1950 | struct task_struct *thread; | |
1da177e4 LT |
1951 | struct memelfnote notes[3]; |
1952 | int num_notes; | |
1953 | }; | |
1954 | ||
1955 | /* | |
1956 | * In order to add the specific thread information for the elf file format, | |
f4e5cc2c JJ |
1957 | * we need to keep a linked list of every threads pr_status and then create |
1958 | * a single section for them in the final core file. | |
1da177e4 LT |
1959 | */ |
1960 | static int elf_dump_thread_status(long signr, struct elf_thread_status *t) | |
1961 | { | |
1962 | int sz = 0; | |
1963 | struct task_struct *p = t->thread; | |
1964 | t->num_notes = 0; | |
1965 | ||
f2485a2d | 1966 | fill_prstatus(&t->prstatus.common, p, signr); |
1da177e4 LT |
1967 | elf_core_copy_task_regs(p, &t->prstatus.pr_reg); |
1968 | ||
f4e5cc2c JJ |
1969 | fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus), |
1970 | &(t->prstatus)); | |
1da177e4 LT |
1971 | t->num_notes++; |
1972 | sz += notesize(&t->notes[0]); | |
1973 | ||
f4e5cc2c JJ |
1974 | if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL, |
1975 | &t->fpu))) { | |
1976 | fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu), | |
1977 | &(t->fpu)); | |
1da177e4 LT |
1978 | t->num_notes++; |
1979 | sz += notesize(&t->notes[1]); | |
1980 | } | |
1da177e4 LT |
1981 | return sz; |
1982 | } | |
1983 | ||
3aba481f RM |
1984 | struct elf_note_info { |
1985 | struct memelfnote *notes; | |
72023656 | 1986 | struct memelfnote *notes_files; |
3aba481f RM |
1987 | struct elf_prstatus *prstatus; /* NT_PRSTATUS */ |
1988 | struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */ | |
1989 | struct list_head thread_list; | |
1990 | elf_fpregset_t *fpu; | |
49ae4d4b | 1991 | user_siginfo_t csigdata; |
3aba481f RM |
1992 | int thread_status_size; |
1993 | int numnote; | |
1994 | }; | |
1995 | ||
0cf062d0 | 1996 | static int elf_note_info_init(struct elf_note_info *info) |
3aba481f | 1997 | { |
0cf062d0 | 1998 | memset(info, 0, sizeof(*info)); |
3aba481f RM |
1999 | INIT_LIST_HEAD(&info->thread_list); |
2000 | ||
49ae4d4b | 2001 | /* Allocate space for ELF notes */ |
6da2ec56 | 2002 | info->notes = kmalloc_array(8, sizeof(struct memelfnote), GFP_KERNEL); |
3aba481f RM |
2003 | if (!info->notes) |
2004 | return 0; | |
2005 | info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL); | |
2006 | if (!info->psinfo) | |
f34f9d18 | 2007 | return 0; |
3aba481f RM |
2008 | info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL); |
2009 | if (!info->prstatus) | |
f34f9d18 | 2010 | return 0; |
3aba481f RM |
2011 | info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL); |
2012 | if (!info->fpu) | |
f34f9d18 | 2013 | return 0; |
0cf062d0 | 2014 | return 1; |
0cf062d0 AW |
2015 | } |
2016 | ||
2017 | static int fill_note_info(struct elfhdr *elf, int phdrs, | |
2018 | struct elf_note_info *info, | |
ae7795bc | 2019 | const kernel_siginfo_t *siginfo, struct pt_regs *regs) |
0cf062d0 | 2020 | { |
afabada9 AV |
2021 | struct core_thread *ct; |
2022 | struct elf_thread_status *ets; | |
0cf062d0 AW |
2023 | |
2024 | if (!elf_note_info_init(info)) | |
2025 | return 0; | |
3aba481f | 2026 | |
afabada9 AV |
2027 | for (ct = current->mm->core_state->dumper.next; |
2028 | ct; ct = ct->next) { | |
2029 | ets = kzalloc(sizeof(*ets), GFP_KERNEL); | |
2030 | if (!ets) | |
2031 | return 0; | |
83914441 | 2032 | |
afabada9 AV |
2033 | ets->thread = ct->task; |
2034 | list_add(&ets->list, &info->thread_list); | |
2035 | } | |
83914441 | 2036 | |
93f044e2 | 2037 | list_for_each_entry(ets, &info->thread_list, list) { |
afabada9 | 2038 | int sz; |
3aba481f | 2039 | |
afabada9 AV |
2040 | sz = elf_dump_thread_status(siginfo->si_signo, ets); |
2041 | info->thread_status_size += sz; | |
3aba481f RM |
2042 | } |
2043 | /* now collect the dump for the current */ | |
2044 | memset(info->prstatus, 0, sizeof(*info->prstatus)); | |
f2485a2d | 2045 | fill_prstatus(&info->prstatus->common, current, siginfo->si_signo); |
3aba481f RM |
2046 | elf_core_copy_regs(&info->prstatus->pr_reg, regs); |
2047 | ||
2048 | /* Set up header */ | |
d3330cf0 | 2049 | fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS); |
3aba481f RM |
2050 | |
2051 | /* | |
2052 | * Set up the notes in similar form to SVR4 core dumps made | |
2053 | * with info from their /proc. | |
2054 | */ | |
2055 | ||
2056 | fill_note(info->notes + 0, "CORE", NT_PRSTATUS, | |
2057 | sizeof(*info->prstatus), info->prstatus); | |
2058 | fill_psinfo(info->psinfo, current->group_leader, current->mm); | |
2059 | fill_note(info->notes + 1, "CORE", NT_PRPSINFO, | |
2060 | sizeof(*info->psinfo), info->psinfo); | |
2061 | ||
2aa362c4 DV |
2062 | fill_siginfo_note(info->notes + 2, &info->csigdata, siginfo); |
2063 | fill_auxv_note(info->notes + 3, current->mm); | |
72023656 | 2064 | info->numnote = 4; |
3aba481f | 2065 | |
72023656 DA |
2066 | if (fill_files_note(info->notes + info->numnote) == 0) { |
2067 | info->notes_files = info->notes + info->numnote; | |
2068 | info->numnote++; | |
2069 | } | |
3aba481f RM |
2070 | |
2071 | /* Try to dump the FPU. */ | |
2072 | info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs, | |
2073 | info->fpu); | |
2074 | if (info->prstatus->pr_fpvalid) | |
2075 | fill_note(info->notes + info->numnote++, | |
2076 | "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu); | |
3aba481f | 2077 | return 1; |
3aba481f RM |
2078 | } |
2079 | ||
2080 | static size_t get_note_info_size(struct elf_note_info *info) | |
2081 | { | |
2082 | int sz = 0; | |
2083 | int i; | |
2084 | ||
2085 | for (i = 0; i < info->numnote; i++) | |
2086 | sz += notesize(info->notes + i); | |
2087 | ||
2088 | sz += info->thread_status_size; | |
2089 | ||
2090 | return sz; | |
2091 | } | |
2092 | ||
2093 | static int write_note_info(struct elf_note_info *info, | |
ecc8c772 | 2094 | struct coredump_params *cprm) |
3aba481f | 2095 | { |
93f044e2 | 2096 | struct elf_thread_status *ets; |
3aba481f | 2097 | int i; |
3aba481f RM |
2098 | |
2099 | for (i = 0; i < info->numnote; i++) | |
ecc8c772 | 2100 | if (!writenote(info->notes + i, cprm)) |
3aba481f RM |
2101 | return 0; |
2102 | ||
2103 | /* write out the thread status notes section */ | |
93f044e2 AD |
2104 | list_for_each_entry(ets, &info->thread_list, list) { |
2105 | for (i = 0; i < ets->num_notes; i++) | |
2106 | if (!writenote(&ets->notes[i], cprm)) | |
3aba481f RM |
2107 | return 0; |
2108 | } | |
2109 | ||
2110 | return 1; | |
2111 | } | |
2112 | ||
2113 | static void free_note_info(struct elf_note_info *info) | |
2114 | { | |
2115 | while (!list_empty(&info->thread_list)) { | |
2116 | struct list_head *tmp = info->thread_list.next; | |
2117 | list_del(tmp); | |
2118 | kfree(list_entry(tmp, struct elf_thread_status, list)); | |
2119 | } | |
2120 | ||
72023656 DA |
2121 | /* Free data possibly allocated by fill_files_note(): */ |
2122 | if (info->notes_files) | |
86a2bb5a | 2123 | kvfree(info->notes_files->data); |
2aa362c4 | 2124 | |
3aba481f RM |
2125 | kfree(info->prstatus); |
2126 | kfree(info->psinfo); | |
2127 | kfree(info->notes); | |
2128 | kfree(info->fpu); | |
3aba481f RM |
2129 | } |
2130 | ||
4206d3aa RM |
2131 | #endif |
2132 | ||
8d9032bb DH |
2133 | static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum, |
2134 | elf_addr_t e_shoff, int segs) | |
2135 | { | |
2136 | elf->e_shoff = e_shoff; | |
2137 | elf->e_shentsize = sizeof(*shdr4extnum); | |
2138 | elf->e_shnum = 1; | |
2139 | elf->e_shstrndx = SHN_UNDEF; | |
2140 | ||
2141 | memset(shdr4extnum, 0, sizeof(*shdr4extnum)); | |
2142 | ||
2143 | shdr4extnum->sh_type = SHT_NULL; | |
2144 | shdr4extnum->sh_size = elf->e_shnum; | |
2145 | shdr4extnum->sh_link = elf->e_shstrndx; | |
2146 | shdr4extnum->sh_info = segs; | |
2147 | } | |
2148 | ||
1da177e4 LT |
2149 | /* |
2150 | * Actual dumper | |
2151 | * | |
2152 | * This is a two-pass process; first we find the offsets of the bits, | |
2153 | * and then they are actually written out. If we run out of core limit | |
2154 | * we just truncate. | |
2155 | */ | |
f6151dfe | 2156 | static int elf_core_dump(struct coredump_params *cprm) |
1da177e4 | 2157 | { |
1da177e4 | 2158 | int has_dumped = 0; |
a07279c9 JH |
2159 | int vma_count, segs, i; |
2160 | size_t vma_data_size; | |
225a3f53 | 2161 | struct elfhdr elf; |
cdc3d562 | 2162 | loff_t offset = 0, dataoff; |
72023656 | 2163 | struct elf_note_info info = { }; |
93eb211e | 2164 | struct elf_phdr *phdr4note = NULL; |
8d9032bb DH |
2165 | struct elf_shdr *shdr4extnum = NULL; |
2166 | Elf_Half e_phnum; | |
2167 | elf_addr_t e_shoff; | |
a07279c9 JH |
2168 | struct core_vma_metadata *vma_meta; |
2169 | ||
2170 | if (dump_vma_snapshot(cprm, &vma_count, &vma_meta, &vma_data_size)) | |
2171 | return 0; | |
1da177e4 | 2172 | |
341c87bf KH |
2173 | /* |
2174 | * The number of segs are recored into ELF header as 16bit value. | |
2175 | * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here. | |
2176 | */ | |
a07279c9 | 2177 | segs = vma_count + elf_core_extra_phdrs(); |
f47aef55 | 2178 | |
8d9032bb DH |
2179 | /* for notes section */ |
2180 | segs++; | |
2181 | ||
2182 | /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid | |
2183 | * this, kernel supports extended numbering. Have a look at | |
2184 | * include/linux/elf.h for further information. */ | |
2185 | e_phnum = segs > PN_XNUM ? PN_XNUM : segs; | |
2186 | ||
1da177e4 | 2187 | /* |
3aba481f RM |
2188 | * Collect all the non-memory information about the process for the |
2189 | * notes. This also sets up the file header. | |
1da177e4 | 2190 | */ |
225a3f53 | 2191 | if (!fill_note_info(&elf, e_phnum, &info, cprm->siginfo, cprm->regs)) |
d2530b43 | 2192 | goto end_coredump; |
1da177e4 | 2193 | |
3aba481f | 2194 | has_dumped = 1; |
079148b9 | 2195 | |
225a3f53 | 2196 | offset += sizeof(elf); /* Elf header */ |
8d9032bb | 2197 | offset += segs * sizeof(struct elf_phdr); /* Program headers */ |
1da177e4 LT |
2198 | |
2199 | /* Write notes phdr entry */ | |
2200 | { | |
3aba481f | 2201 | size_t sz = get_note_info_size(&info); |
1da177e4 | 2202 | |
c39ab6de | 2203 | /* For cell spufs */ |
e5501492 | 2204 | sz += elf_coredump_extra_notes_size(); |
bf1ab978 | 2205 | |
93eb211e DH |
2206 | phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL); |
2207 | if (!phdr4note) | |
088e7af7 | 2208 | goto end_coredump; |
93eb211e DH |
2209 | |
2210 | fill_elf_note_phdr(phdr4note, sz, offset); | |
2211 | offset += sz; | |
1da177e4 LT |
2212 | } |
2213 | ||
1da177e4 LT |
2214 | dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE); |
2215 | ||
52f5592e | 2216 | offset += vma_data_size; |
8d9032bb DH |
2217 | offset += elf_core_extra_data_size(); |
2218 | e_shoff = offset; | |
2219 | ||
2220 | if (e_phnum == PN_XNUM) { | |
2221 | shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL); | |
2222 | if (!shdr4extnum) | |
2223 | goto end_coredump; | |
225a3f53 | 2224 | fill_extnum_info(&elf, shdr4extnum, e_shoff, segs); |
8d9032bb DH |
2225 | } |
2226 | ||
2227 | offset = dataoff; | |
2228 | ||
225a3f53 | 2229 | if (!dump_emit(cprm, &elf, sizeof(elf))) |
93eb211e DH |
2230 | goto end_coredump; |
2231 | ||
ecc8c772 | 2232 | if (!dump_emit(cprm, phdr4note, sizeof(*phdr4note))) |
93eb211e DH |
2233 | goto end_coredump; |
2234 | ||
1da177e4 | 2235 | /* Write program headers for segments dump */ |
a07279c9 JH |
2236 | for (i = 0; i < vma_count; i++) { |
2237 | struct core_vma_metadata *meta = vma_meta + i; | |
1da177e4 | 2238 | struct elf_phdr phdr; |
1da177e4 LT |
2239 | |
2240 | phdr.p_type = PT_LOAD; | |
2241 | phdr.p_offset = offset; | |
a07279c9 | 2242 | phdr.p_vaddr = meta->start; |
1da177e4 | 2243 | phdr.p_paddr = 0; |
a07279c9 JH |
2244 | phdr.p_filesz = meta->dump_size; |
2245 | phdr.p_memsz = meta->end - meta->start; | |
1da177e4 | 2246 | offset += phdr.p_filesz; |
a07279c9 JH |
2247 | phdr.p_flags = 0; |
2248 | if (meta->flags & VM_READ) | |
2249 | phdr.p_flags |= PF_R; | |
2250 | if (meta->flags & VM_WRITE) | |
f4e5cc2c | 2251 | phdr.p_flags |= PF_W; |
a07279c9 | 2252 | if (meta->flags & VM_EXEC) |
f4e5cc2c | 2253 | phdr.p_flags |= PF_X; |
1da177e4 LT |
2254 | phdr.p_align = ELF_EXEC_PAGESIZE; |
2255 | ||
ecc8c772 | 2256 | if (!dump_emit(cprm, &phdr, sizeof(phdr))) |
088e7af7 | 2257 | goto end_coredump; |
1da177e4 LT |
2258 | } |
2259 | ||
506f21c5 | 2260 | if (!elf_core_write_extra_phdrs(cprm, offset)) |
1fcccbac | 2261 | goto end_coredump; |
1da177e4 LT |
2262 | |
2263 | /* write out the notes section */ | |
ecc8c772 | 2264 | if (!write_note_info(&info, cprm)) |
3aba481f | 2265 | goto end_coredump; |
1da177e4 | 2266 | |
c39ab6de | 2267 | /* For cell spufs */ |
cdc3d562 | 2268 | if (elf_coredump_extra_notes_write(cprm)) |
e5501492 | 2269 | goto end_coredump; |
bf1ab978 | 2270 | |
d025c9db | 2271 | /* Align to page */ |
d0f1088b | 2272 | dump_skip_to(cprm, dataoff); |
1da177e4 | 2273 | |
a07279c9 JH |
2274 | for (i = 0; i < vma_count; i++) { |
2275 | struct core_vma_metadata *meta = vma_meta + i; | |
2276 | ||
2277 | if (!dump_user_range(cprm, meta->start, meta->dump_size)) | |
afc63a97 | 2278 | goto end_coredump; |
1da177e4 LT |
2279 | } |
2280 | ||
aa3e7eaf | 2281 | if (!elf_core_write_extra_data(cprm)) |
1fcccbac | 2282 | goto end_coredump; |
1da177e4 | 2283 | |
8d9032bb | 2284 | if (e_phnum == PN_XNUM) { |
13046ece | 2285 | if (!dump_emit(cprm, shdr4extnum, sizeof(*shdr4extnum))) |
8d9032bb DH |
2286 | goto end_coredump; |
2287 | } | |
2288 | ||
1da177e4 | 2289 | end_coredump: |
3aba481f | 2290 | free_note_info(&info); |
8d9032bb | 2291 | kfree(shdr4extnum); |
a07279c9 | 2292 | kvfree(vma_meta); |
93eb211e | 2293 | kfree(phdr4note); |
1da177e4 | 2294 | return has_dumped; |
1da177e4 LT |
2295 | } |
2296 | ||
698ba7b5 | 2297 | #endif /* CONFIG_ELF_CORE */ |
1da177e4 LT |
2298 | |
2299 | static int __init init_elf_binfmt(void) | |
2300 | { | |
8fc3dc5a AV |
2301 | register_binfmt(&elf_format); |
2302 | return 0; | |
1da177e4 LT |
2303 | } |
2304 | ||
2305 | static void __exit exit_elf_binfmt(void) | |
2306 | { | |
2307 | /* Remove the COFF and ELF loaders. */ | |
2308 | unregister_binfmt(&elf_format); | |
2309 | } | |
2310 | ||
2311 | core_initcall(init_elf_binfmt); | |
2312 | module_exit(exit_elf_binfmt); | |
2313 | MODULE_LICENSE("GPL"); |