projects/linux·blob 4563243e · refs

389 lines · 7.7 KiB

1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * sorttable.c: Sort the kernel's table
4 *
5 * Added ORC unwind tables sort support and other updates:
6 * Copyright (C) 1999-2019 Alibaba Group Holding Limited. by:
7 * Shile Zhang <[email protected]>
8 *
9 * Copyright 2011 - 2012 Cavium, Inc.
10 *
11 * Based on code taken from recortmcount.c which is:
12 *
13 * Copyright 2009 John F. Reiser <[email protected]>. All rights reserved.
14 *
15 * Restructured to fit Linux format, as well as other updates:
16 * Copyright 2010 Steven Rostedt <[email protected]>, Red Hat Inc.
17 */
18
19/*
20 * Strategy: alter the vmlinux file in-place.
21 */
22
23#include <sys/types.h>
24#include <sys/mman.h>
25#include <sys/stat.h>
26#include <getopt.h>
27#include <elf.h>
28#include <fcntl.h>
29#include <stdio.h>
30#include <stdlib.h>
31#include <string.h>
32#include <unistd.h>
33#include <errno.h>
34#include <pthread.h>
35
36#include <tools/be_byteshift.h>
37#include <tools/le_byteshift.h>
38
39#ifndef EM_ARCOMPACT
40#define EM_ARCOMPACT 93
41#endif
42
43#ifndef EM_XTENSA
44#define EM_XTENSA 94
45#endif
46
47#ifndef EM_AARCH64
48#define EM_AARCH64 183
49#endif
50
51#ifndef EM_MICROBLAZE
52#define EM_MICROBLAZE 189
53#endif
54
55#ifndef EM_ARCV2
56#define EM_ARCV2 195
57#endif
58
59#ifndef EM_RISCV
60#define EM_RISCV 243
61#endif
62
63#ifndef EM_LOONGARCH
64#define EM_LOONGARCH 258
65#endif
66
67static uint32_t (*r)(const uint32_t *);
68static uint16_t (*r2)(const uint16_t *);
69static uint64_t (*r8)(const uint64_t *);
70static void (*w)(uint32_t, uint32_t *);
71static void (*w2)(uint16_t, uint16_t *);
72static void (*w8)(uint64_t, uint64_t *);
73typedef void (*table_sort_t)(char *, int);
74
75/*
76 * Get the whole file as a programming convenience in order to avoid
77 * malloc+lseek+read+free of many pieces. If successful, then mmap
78 * avoids copying unused pieces; else just read the whole file.
79 * Open for both read and write.
80 */
81static void *mmap_file(char const *fname, size_t *size)
82{
83 int fd;
84 struct stat sb;
85 void *addr = NULL;
86
87 fd = open(fname, O_RDWR);
88 if (fd < 0) {
89 perror(fname);
90 return NULL;
91 }
92 if (fstat(fd, &sb) < 0) {
93 perror(fname);
94 goto out;
95 }
96 if (!S_ISREG(sb.st_mode)) {
97 fprintf(stderr, "not a regular file: %s\n", fname);
98 goto out;
99 }
100
101 addr = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
102 if (addr == MAP_FAILED) {
103 fprintf(stderr, "Could not mmap file: %s\n", fname);
104 goto out;
105 }
106
107 *size = sb.st_size;
108
109out:
110 close(fd);
111 return addr;
112}
113
114static uint32_t rbe(const uint32_t *x)
115{
116 return get_unaligned_be32(x);
117}
118
119static uint16_t r2be(const uint16_t *x)
120{
121 return get_unaligned_be16(x);
122}
123
124static uint64_t r8be(const uint64_t *x)
125{
126 return get_unaligned_be64(x);
127}
128
129static uint32_t rle(const uint32_t *x)
130{
131 return get_unaligned_le32(x);
132}
133
134static uint16_t r2le(const uint16_t *x)
135{
136 return get_unaligned_le16(x);
137}
138
139static uint64_t r8le(const uint64_t *x)
140{
141 return get_unaligned_le64(x);
142}
143
144static void wbe(uint32_t val, uint32_t *x)
145{
146 put_unaligned_be32(val, x);
147}
148
149static void w2be(uint16_t val, uint16_t *x)
150{
151 put_unaligned_be16(val, x);
152}
153
154static void w8be(uint64_t val, uint64_t *x)
155{
156 put_unaligned_be64(val, x);
157}
158
159static void wle(uint32_t val, uint32_t *x)
160{
161 put_unaligned_le32(val, x);
162}
163
164static void w2le(uint16_t val, uint16_t *x)
165{
166 put_unaligned_le16(val, x);
167}
168
169static void w8le(uint64_t val, uint64_t *x)
170{
171 put_unaligned_le64(val, x);
172}
173
174/*
175 * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of
176 * the way to -256..-1, to avoid conflicting with real section
177 * indices.
178 */
179#define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1))
180
181static inline int is_shndx_special(unsigned int i)
182{
183 return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE;
184}
185
186/* Accessor for sym->st_shndx, hides ugliness of "64k sections" */
187static inline unsigned int get_secindex(unsigned int shndx,
188 unsigned int sym_offs,
189 const Elf32_Word *symtab_shndx_start)
190{
191 if (is_shndx_special(shndx))
192 return SPECIAL(shndx);
193 if (shndx != SHN_XINDEX)
194 return shndx;
195 return r(&symtab_shndx_start[sym_offs]);
196}
197
198/* 32 bit and 64 bit are very similar */
199#include "sorttable.h"
200#define SORTTABLE_64
201#include "sorttable.h"
202
203static int compare_relative_table(const void *a, const void *b)
204{
205 int32_t av = (int32_t)r(a);
206 int32_t bv = (int32_t)r(b);
207
208 if (av < bv)
209 return -1;
210 if (av > bv)
211 return 1;
212 return 0;
213}
214
215static void sort_relative_table(char *extab_image, int image_size)
216{
217 int i = 0;
218
219 /*
220 * Do the same thing the runtime sort does, first normalize to
221 * being relative to the start of the section.
222 */
223 while (i < image_size) {
224 uint32_t *loc = (uint32_t *)(extab_image + i);
225 w(r(loc) + i, loc);
226 i += 4;
227 }
228
229 qsort(extab_image, image_size / 8, 8, compare_relative_table);
230
231 /* Now denormalize. */
232 i = 0;
233 while (i < image_size) {
234 uint32_t *loc = (uint32_t *)(extab_image + i);
235 w(r(loc) - i, loc);
236 i += 4;
237 }
238}
239
240static void sort_relative_table_with_data(char *extab_image, int image_size)
241{
242 int i = 0;
243
244 while (i < image_size) {
245 uint32_t *loc = (uint32_t *)(extab_image + i);
246
247 w(r(loc) + i, loc);
248 w(r(loc + 1) + i + 4, loc + 1);
249 /* Don't touch the fixup type or data */
250
251 i += sizeof(uint32_t) * 3;
252 }
253
254 qsort(extab_image, image_size / 12, 12, compare_relative_table);
255
256 i = 0;
257 while (i < image_size) {
258 uint32_t *loc = (uint32_t *)(extab_image + i);
259
260 w(r(loc) - i, loc);
261 w(r(loc + 1) - (i + 4), loc + 1);
262 /* Don't touch the fixup type or data */
263
264 i += sizeof(uint32_t) * 3;
265 }
266}
267
268static int do_file(char const *const fname, void *addr)
269{
270 int rc = -1;
271 Elf32_Ehdr *ehdr = addr;
272 table_sort_t custom_sort = NULL;
273
274 switch (ehdr->e_ident[EI_DATA]) {
275 case ELFDATA2LSB:
276 r = rle;
277 r2 = r2le;
278 r8 = r8le;
279 w = wle;
280 w2 = w2le;
281 w8 = w8le;
282 break;
283 case ELFDATA2MSB:
284 r = rbe;
285 r2 = r2be;
286 r8 = r8be;
287 w = wbe;
288 w2 = w2be;
289 w8 = w8be;
290 break;
291 default:
292 fprintf(stderr, "unrecognized ELF data encoding %d: %s\n",
293 ehdr->e_ident[EI_DATA], fname);
294 return -1;
295 }
296
297 if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 ||
298 (r2(&ehdr->e_type) != ET_EXEC && r2(&ehdr->e_type) != ET_DYN) ||
299 ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
300 fprintf(stderr, "unrecognized ET_EXEC/ET_DYN file %s\n", fname);
301 return -1;
302 }
303
304 switch (r2(&ehdr->e_machine)) {
305 case EM_386:
306 case EM_AARCH64:
307 case EM_LOONGARCH:
308 case EM_RISCV:
309 case EM_S390:
310 case EM_X86_64:
311 custom_sort = sort_relative_table_with_data;
312 break;
313 case EM_PARISC:
314 case EM_PPC:
315 case EM_PPC64:
316 custom_sort = sort_relative_table;
317 break;
318 case EM_ARCOMPACT:
319 case EM_ARCV2:
320 case EM_ARM:
321 case EM_MICROBLAZE:
322 case EM_MIPS:
323 case EM_XTENSA:
324 break;
325 default:
326 fprintf(stderr, "unrecognized e_machine %d %s\n",
327 r2(&ehdr->e_machine), fname);
328 return -1;
329 }
330
331 switch (ehdr->e_ident[EI_CLASS]) {
332 case ELFCLASS32:
333 if (r2(&ehdr->e_ehsize) != sizeof(Elf32_Ehdr) ||
334 r2(&ehdr->e_shentsize) != sizeof(Elf32_Shdr)) {
335 fprintf(stderr,
336 "unrecognized ET_EXEC/ET_DYN file: %s\n", fname);
337 break;
338 }
339 rc = do_sort_32(ehdr, fname, custom_sort);
340 break;
341 case ELFCLASS64:
342 {
343 Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr;
344 if (r2(&ghdr->e_ehsize) != sizeof(Elf64_Ehdr) ||
345 r2(&ghdr->e_shentsize) != sizeof(Elf64_Shdr)) {
346 fprintf(stderr,
347 "unrecognized ET_EXEC/ET_DYN file: %s\n",
348 fname);
349 break;
350 }
351 rc = do_sort_64(ghdr, fname, custom_sort);
352 }
353 break;
354 default:
355 fprintf(stderr, "unrecognized ELF class %d %s\n",
356 ehdr->e_ident[EI_CLASS], fname);
357 break;
358 }
359
360 return rc;
361}
362
363int main(int argc, char *argv[])
364{
365 int i, n_error = 0; /* gcc-4.3.0 false positive complaint */
366 size_t size = 0;
367 void *addr = NULL;
368
369 if (argc < 2) {
370 fprintf(stderr, "usage: sorttable vmlinux...\n");
371 return 0;
372 }
373
374 /* Process each file in turn, allowing deep failure. */
375 for (i = 1; i < argc; i++) {
376 addr = mmap_file(argv[i], &size);
377 if (!addr) {
378 ++n_error;
379 continue;
380 }
381
382 if (do_file(argv[i], addr))
383 ++n_error;
384
385 munmap(addr, size);
386 }
387
388 return !!n_error;
389}