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Commit | Line | Data |
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a79f248b DD |
1 | /* |
2 | * sortextable.c: Sort the kernel's exception table | |
3 | * | |
d59a1683 | 4 | * Copyright 2011 - 2012 Cavium, Inc. |
a79f248b DD |
5 | * |
6 | * Based on code taken from recortmcount.c which is: | |
7 | * | |
8 | * Copyright 2009 John F. Reiser <[email protected]>. All rights reserved. | |
9 | * Licensed under the GNU General Public License, version 2 (GPLv2). | |
10 | * | |
11 | * Restructured to fit Linux format, as well as other updates: | |
12 | * Copyright 2010 Steven Rostedt <[email protected]>, Red Hat Inc. | |
13 | */ | |
14 | ||
15 | /* | |
16 | * Strategy: alter the vmlinux file in-place. | |
17 | */ | |
18 | ||
19 | #include <sys/types.h> | |
20 | #include <sys/mman.h> | |
21 | #include <sys/stat.h> | |
22 | #include <getopt.h> | |
23 | #include <elf.h> | |
24 | #include <fcntl.h> | |
25 | #include <setjmp.h> | |
26 | #include <stdio.h> | |
27 | #include <stdlib.h> | |
28 | #include <string.h> | |
29 | #include <unistd.h> | |
30 | ||
d59a1683 DD |
31 | #include <tools/be_byteshift.h> |
32 | #include <tools/le_byteshift.h> | |
33 | ||
f06d19e4 VG |
34 | #ifndef EM_ARCOMPACT |
35 | #define EM_ARCOMPACT 93 | |
36 | #endif | |
37 | ||
25df8198 MF |
38 | #ifndef EM_XTENSA |
39 | #define EM_XTENSA 94 | |
40 | #endif | |
41 | ||
adace895 WD |
42 | #ifndef EM_AARCH64 |
43 | #define EM_AARCH64 183 | |
44 | #endif | |
45 | ||
372c7209 MS |
46 | #ifndef EM_MICROBLAZE |
47 | #define EM_MICROBLAZE 189 | |
48 | #endif | |
49 | ||
b3210d14 VG |
50 | #ifndef EM_ARCV2 |
51 | #define EM_ARCV2 195 | |
52 | #endif | |
53 | ||
a79f248b DD |
54 | static int fd_map; /* File descriptor for file being modified. */ |
55 | static int mmap_failed; /* Boolean flag. */ | |
56 | static void *ehdr_curr; /* current ElfXX_Ehdr * for resource cleanup */ | |
57 | static struct stat sb; /* Remember .st_size, etc. */ | |
58 | static jmp_buf jmpenv; /* setjmp/longjmp per-file error escape */ | |
59 | ||
60 | /* setjmp() return values */ | |
61 | enum { | |
62 | SJ_SETJMP = 0, /* hardwired first return */ | |
63 | SJ_FAIL, | |
64 | SJ_SUCCEED | |
65 | }; | |
66 | ||
67 | /* Per-file resource cleanup when multiple files. */ | |
68 | static void | |
69 | cleanup(void) | |
70 | { | |
71 | if (!mmap_failed) | |
72 | munmap(ehdr_curr, sb.st_size); | |
73 | close(fd_map); | |
74 | } | |
75 | ||
76 | static void __attribute__((noreturn)) | |
77 | fail_file(void) | |
78 | { | |
79 | cleanup(); | |
80 | longjmp(jmpenv, SJ_FAIL); | |
81 | } | |
82 | ||
a79f248b DD |
83 | /* |
84 | * Get the whole file as a programming convenience in order to avoid | |
85 | * malloc+lseek+read+free of many pieces. If successful, then mmap | |
86 | * avoids copying unused pieces; else just read the whole file. | |
87 | * Open for both read and write. | |
88 | */ | |
89 | static void *mmap_file(char const *fname) | |
90 | { | |
91 | void *addr; | |
92 | ||
93 | fd_map = open(fname, O_RDWR); | |
94 | if (fd_map < 0 || fstat(fd_map, &sb) < 0) { | |
95 | perror(fname); | |
96 | fail_file(); | |
97 | } | |
98 | if (!S_ISREG(sb.st_mode)) { | |
99 | fprintf(stderr, "not a regular file: %s\n", fname); | |
100 | fail_file(); | |
101 | } | |
102 | addr = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_SHARED, | |
103 | fd_map, 0); | |
104 | if (addr == MAP_FAILED) { | |
105 | mmap_failed = 1; | |
106 | fprintf(stderr, "Could not mmap file: %s\n", fname); | |
107 | fail_file(); | |
108 | } | |
109 | return addr; | |
110 | } | |
111 | ||
d59a1683 | 112 | static uint64_t r8be(const uint64_t *x) |
a79f248b | 113 | { |
d59a1683 | 114 | return get_unaligned_be64(x); |
a79f248b | 115 | } |
d59a1683 | 116 | static uint32_t rbe(const uint32_t *x) |
a79f248b | 117 | { |
d59a1683 | 118 | return get_unaligned_be32(x); |
a79f248b | 119 | } |
d59a1683 | 120 | static uint16_t r2be(const uint16_t *x) |
a79f248b | 121 | { |
d59a1683 | 122 | return get_unaligned_be16(x); |
a79f248b | 123 | } |
d59a1683 | 124 | static uint64_t r8le(const uint64_t *x) |
a79f248b | 125 | { |
d59a1683 | 126 | return get_unaligned_le64(x); |
a79f248b | 127 | } |
d59a1683 DD |
128 | static uint32_t rle(const uint32_t *x) |
129 | { | |
130 | return get_unaligned_le32(x); | |
131 | } | |
132 | static uint16_t r2le(const uint16_t *x) | |
a79f248b | 133 | { |
d59a1683 | 134 | return get_unaligned_le16(x); |
a79f248b DD |
135 | } |
136 | ||
d59a1683 DD |
137 | static void w8be(uint64_t val, uint64_t *x) |
138 | { | |
139 | put_unaligned_be64(val, x); | |
140 | } | |
141 | static void wbe(uint32_t val, uint32_t *x) | |
142 | { | |
143 | put_unaligned_be32(val, x); | |
144 | } | |
145 | static void w2be(uint16_t val, uint16_t *x) | |
146 | { | |
147 | put_unaligned_be16(val, x); | |
148 | } | |
149 | static void w8le(uint64_t val, uint64_t *x) | |
150 | { | |
151 | put_unaligned_le64(val, x); | |
152 | } | |
153 | static void wle(uint32_t val, uint32_t *x) | |
154 | { | |
155 | put_unaligned_le32(val, x); | |
156 | } | |
157 | static void w2le(uint16_t val, uint16_t *x) | |
a79f248b | 158 | { |
d59a1683 | 159 | put_unaligned_le16(val, x); |
a79f248b DD |
160 | } |
161 | ||
d59a1683 DD |
162 | static uint64_t (*r8)(const uint64_t *); |
163 | static uint32_t (*r)(const uint32_t *); | |
164 | static uint16_t (*r2)(const uint16_t *); | |
165 | static void (*w8)(uint64_t, uint64_t *); | |
166 | static void (*w)(uint32_t, uint32_t *); | |
167 | static void (*w2)(uint16_t, uint16_t *); | |
a79f248b | 168 | |
d59a1683 | 169 | typedef void (*table_sort_t)(char *, int); |
a79f248b | 170 | |
59c36455 JI |
171 | /* |
172 | * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of | |
173 | * the way to -256..-1, to avoid conflicting with real section | |
174 | * indices. | |
175 | */ | |
176 | #define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1)) | |
177 | ||
178 | static inline int is_shndx_special(unsigned int i) | |
179 | { | |
180 | return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE; | |
181 | } | |
182 | ||
183 | /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */ | |
184 | static inline unsigned int get_secindex(unsigned int shndx, | |
185 | unsigned int sym_offs, | |
186 | const Elf32_Word *symtab_shndx_start) | |
187 | { | |
188 | if (is_shndx_special(shndx)) | |
189 | return SPECIAL(shndx); | |
190 | if (shndx != SHN_XINDEX) | |
191 | return shndx; | |
192 | return r(&symtab_shndx_start[sym_offs]); | |
193 | } | |
194 | ||
a79f248b DD |
195 | /* 32 bit and 64 bit are very similar */ |
196 | #include "sortextable.h" | |
197 | #define SORTEXTABLE_64 | |
198 | #include "sortextable.h" | |
199 | ||
eb608fb3 | 200 | static int compare_relative_table(const void *a, const void *b) |
d59a1683 DD |
201 | { |
202 | int32_t av = (int32_t)r(a); | |
203 | int32_t bv = (int32_t)r(b); | |
204 | ||
205 | if (av < bv) | |
206 | return -1; | |
207 | if (av > bv) | |
208 | return 1; | |
209 | return 0; | |
210 | } | |
211 | ||
548acf19 TL |
212 | static void x86_sort_relative_table(char *extab_image, int image_size) |
213 | { | |
214 | int i; | |
215 | ||
216 | i = 0; | |
217 | while (i < image_size) { | |
218 | uint32_t *loc = (uint32_t *)(extab_image + i); | |
219 | ||
220 | w(r(loc) + i, loc); | |
221 | w(r(loc + 1) + i + 4, loc + 1); | |
222 | w(r(loc + 2) + i + 8, loc + 2); | |
223 | ||
224 | i += sizeof(uint32_t) * 3; | |
225 | } | |
226 | ||
227 | qsort(extab_image, image_size / 12, 12, compare_relative_table); | |
228 | ||
229 | i = 0; | |
230 | while (i < image_size) { | |
231 | uint32_t *loc = (uint32_t *)(extab_image + i); | |
232 | ||
233 | w(r(loc) - i, loc); | |
234 | w(r(loc + 1) - (i + 4), loc + 1); | |
235 | w(r(loc + 2) - (i + 8), loc + 2); | |
236 | ||
237 | i += sizeof(uint32_t) * 3; | |
238 | } | |
239 | } | |
240 | ||
eb608fb3 | 241 | static void sort_relative_table(char *extab_image, int image_size) |
d59a1683 DD |
242 | { |
243 | int i; | |
244 | ||
245 | /* | |
246 | * Do the same thing the runtime sort does, first normalize to | |
247 | * being relative to the start of the section. | |
248 | */ | |
249 | i = 0; | |
250 | while (i < image_size) { | |
251 | uint32_t *loc = (uint32_t *)(extab_image + i); | |
252 | w(r(loc) + i, loc); | |
253 | i += 4; | |
254 | } | |
255 | ||
eb608fb3 | 256 | qsort(extab_image, image_size / 8, 8, compare_relative_table); |
d59a1683 DD |
257 | |
258 | /* Now denormalize. */ | |
259 | i = 0; | |
260 | while (i < image_size) { | |
261 | uint32_t *loc = (uint32_t *)(extab_image + i); | |
262 | w(r(loc) - i, loc); | |
263 | i += 4; | |
264 | } | |
265 | } | |
a79f248b DD |
266 | |
267 | static void | |
268 | do_file(char const *const fname) | |
269 | { | |
d59a1683 DD |
270 | table_sort_t custom_sort; |
271 | Elf32_Ehdr *ehdr = mmap_file(fname); | |
a79f248b DD |
272 | |
273 | ehdr_curr = ehdr; | |
a79f248b | 274 | switch (ehdr->e_ident[EI_DATA]) { |
a79f248b DD |
275 | default: |
276 | fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", | |
277 | ehdr->e_ident[EI_DATA], fname); | |
278 | fail_file(); | |
279 | break; | |
280 | case ELFDATA2LSB: | |
d59a1683 DD |
281 | r = rle; |
282 | r2 = r2le; | |
283 | r8 = r8le; | |
284 | w = wle; | |
285 | w2 = w2le; | |
286 | w8 = w8le; | |
a79f248b DD |
287 | break; |
288 | case ELFDATA2MSB: | |
d59a1683 DD |
289 | r = rbe; |
290 | r2 = r2be; | |
291 | r8 = r8be; | |
292 | w = wbe; | |
293 | w2 = w2be; | |
294 | w8 = w8be; | |
a79f248b DD |
295 | break; |
296 | } /* end switch */ | |
297 | if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 | |
7b957b6e | 298 | || (r2(&ehdr->e_type) != ET_EXEC && r2(&ehdr->e_type) != ET_DYN) |
a79f248b | 299 | || ehdr->e_ident[EI_VERSION] != EV_CURRENT) { |
7b957b6e | 300 | fprintf(stderr, "unrecognized ET_EXEC/ET_DYN file %s\n", fname); |
a79f248b DD |
301 | fail_file(); |
302 | } | |
303 | ||
d59a1683 DD |
304 | custom_sort = NULL; |
305 | switch (r2(&ehdr->e_machine)) { | |
a79f248b DD |
306 | default: |
307 | fprintf(stderr, "unrecognized e_machine %d %s\n", | |
d59a1683 | 308 | r2(&ehdr->e_machine), fname); |
a79f248b DD |
309 | fail_file(); |
310 | break; | |
311 | case EM_386: | |
a79f248b | 312 | case EM_X86_64: |
548acf19 TL |
313 | custom_sort = x86_sort_relative_table; |
314 | break; | |
315 | ||
3193a98d | 316 | case EM_S390: |
6c94f27a | 317 | case EM_AARCH64: |
0de79858 | 318 | case EM_PARISC: |
5b9ff027 NP |
319 | case EM_PPC: |
320 | case EM_PPC64: | |
eb608fb3 HC |
321 | custom_sort = sort_relative_table; |
322 | break; | |
f06d19e4 | 323 | case EM_ARCOMPACT: |
b3210d14 | 324 | case EM_ARCV2: |
ee951c63 | 325 | case EM_ARM: |
372c7209 | 326 | case EM_MICROBLAZE: |
d59a1683 | 327 | case EM_MIPS: |
25df8198 | 328 | case EM_XTENSA: |
a79f248b DD |
329 | break; |
330 | } /* end switch */ | |
331 | ||
332 | switch (ehdr->e_ident[EI_CLASS]) { | |
333 | default: | |
334 | fprintf(stderr, "unrecognized ELF class %d %s\n", | |
335 | ehdr->e_ident[EI_CLASS], fname); | |
336 | fail_file(); | |
337 | break; | |
338 | case ELFCLASS32: | |
d59a1683 DD |
339 | if (r2(&ehdr->e_ehsize) != sizeof(Elf32_Ehdr) |
340 | || r2(&ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { | |
a79f248b | 341 | fprintf(stderr, |
7b957b6e | 342 | "unrecognized ET_EXEC/ET_DYN file: %s\n", fname); |
a79f248b DD |
343 | fail_file(); |
344 | } | |
d59a1683 | 345 | do32(ehdr, fname, custom_sort); |
a79f248b DD |
346 | break; |
347 | case ELFCLASS64: { | |
348 | Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr; | |
d59a1683 DD |
349 | if (r2(&ghdr->e_ehsize) != sizeof(Elf64_Ehdr) |
350 | || r2(&ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { | |
a79f248b | 351 | fprintf(stderr, |
7b957b6e | 352 | "unrecognized ET_EXEC/ET_DYN file: %s\n", fname); |
a79f248b DD |
353 | fail_file(); |
354 | } | |
d59a1683 | 355 | do64(ghdr, fname, custom_sort); |
a79f248b DD |
356 | break; |
357 | } | |
358 | } /* end switch */ | |
359 | ||
360 | cleanup(); | |
361 | } | |
362 | ||
363 | int | |
364 | main(int argc, char *argv[]) | |
365 | { | |
366 | int n_error = 0; /* gcc-4.3.0 false positive complaint */ | |
367 | int i; | |
368 | ||
369 | if (argc < 2) { | |
370 | fprintf(stderr, "usage: sortextable vmlinux...\n"); | |
371 | return 0; | |
372 | } | |
373 | ||
374 | /* Process each file in turn, allowing deep failure. */ | |
375 | for (i = 1; i < argc; i++) { | |
376 | char *file = argv[i]; | |
377 | int const sjval = setjmp(jmpenv); | |
378 | ||
379 | switch (sjval) { | |
380 | default: | |
381 | fprintf(stderr, "internal error: %s\n", file); | |
382 | exit(1); | |
383 | break; | |
384 | case SJ_SETJMP: /* normal sequence */ | |
385 | /* Avoid problems if early cleanup() */ | |
386 | fd_map = -1; | |
387 | ehdr_curr = NULL; | |
388 | mmap_failed = 1; | |
389 | do_file(file); | |
390 | break; | |
391 | case SJ_FAIL: /* error in do_file or below */ | |
392 | ++n_error; | |
393 | break; | |
394 | case SJ_SUCCEED: /* premature success */ | |
395 | /* do nothing */ | |
396 | break; | |
397 | } /* end switch */ | |
398 | } | |
399 | return !!n_error; | |
400 | } |