xref: /openbmc/linux/scripts/sorttable.c (revision 26bc8244)
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 <shile.zhang@linux.alibaba.com>
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 <jreiser@BitWagon.com>.  All rights reserved.
14  *
15  * Restructured to fit Linux format, as well as other updates:
16  * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, 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 
67 static uint32_t (*r)(const uint32_t *);
68 static uint16_t (*r2)(const uint16_t *);
69 static uint64_t (*r8)(const uint64_t *);
70 static void (*w)(uint32_t, uint32_t *);
71 static void (*w2)(uint16_t, uint16_t *);
72 static void (*w8)(uint64_t, uint64_t *);
73 typedef 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  */
mmap_file(char const * fname,size_t * size)81 static 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 
109 out:
110 	close(fd);
111 	return addr;
112 }
113 
rbe(const uint32_t * x)114 static uint32_t rbe(const uint32_t *x)
115 {
116 	return get_unaligned_be32(x);
117 }
118 
r2be(const uint16_t * x)119 static uint16_t r2be(const uint16_t *x)
120 {
121 	return get_unaligned_be16(x);
122 }
123 
r8be(const uint64_t * x)124 static uint64_t r8be(const uint64_t *x)
125 {
126 	return get_unaligned_be64(x);
127 }
128 
rle(const uint32_t * x)129 static uint32_t rle(const uint32_t *x)
130 {
131 	return get_unaligned_le32(x);
132 }
133 
r2le(const uint16_t * x)134 static uint16_t r2le(const uint16_t *x)
135 {
136 	return get_unaligned_le16(x);
137 }
138 
r8le(const uint64_t * x)139 static uint64_t r8le(const uint64_t *x)
140 {
141 	return get_unaligned_le64(x);
142 }
143 
wbe(uint32_t val,uint32_t * x)144 static void wbe(uint32_t val, uint32_t *x)
145 {
146 	put_unaligned_be32(val, x);
147 }
148 
w2be(uint16_t val,uint16_t * x)149 static void w2be(uint16_t val, uint16_t *x)
150 {
151 	put_unaligned_be16(val, x);
152 }
153 
w8be(uint64_t val,uint64_t * x)154 static void w8be(uint64_t val, uint64_t *x)
155 {
156 	put_unaligned_be64(val, x);
157 }
158 
wle(uint32_t val,uint32_t * x)159 static void wle(uint32_t val, uint32_t *x)
160 {
161 	put_unaligned_le32(val, x);
162 }
163 
w2le(uint16_t val,uint16_t * x)164 static void w2le(uint16_t val, uint16_t *x)
165 {
166 	put_unaligned_le16(val, x);
167 }
168 
w8le(uint64_t val,uint64_t * x)169 static 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 
is_shndx_special(unsigned int i)181 static 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" */
get_secindex(unsigned int shndx,unsigned int sym_offs,const Elf32_Word * symtab_shndx_start)187 static 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 
compare_relative_table(const void * a,const void * b)203 static 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 
sort_relative_table(char * extab_image,int image_size)215 static 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 
sort_relative_table_with_data(char * extab_image,int image_size)240 static 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 
do_file(char const * const fname,void * addr)268 static 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 
main(int argc,char * argv[])363 int 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 }
390