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-rw-r--r--scripts/mod/modpost.c188
1 files changed, 144 insertions, 44 deletions
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 3318692e4e76..97d2259ae999 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -14,6 +14,7 @@
#define _GNU_SOURCE
#include <stdio.h>
#include <ctype.h>
+#include <string.h>
#include "modpost.h"
#include "../../include/generated/autoconf.h"
#include "../../include/linux/license.h"
@@ -253,7 +254,7 @@ static enum export export_no(const char *s)
return export_unknown;
}
-static enum export export_from_sec(struct elf_info *elf, Elf_Section sec)
+static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
{
if (sec == elf->export_sec)
return export_plain;
@@ -373,6 +374,8 @@ static int parse_elf(struct elf_info *info, const char *filename)
Elf_Ehdr *hdr;
Elf_Shdr *sechdrs;
Elf_Sym *sym;
+ const char *secstrings;
+ unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
hdr = grab_file(filename, &info->size);
if (!hdr) {
@@ -417,8 +420,27 @@ static int parse_elf(struct elf_info *info, const char *filename)
return 0;
}
+ if (hdr->e_shnum == 0) {
+ /*
+ * There are more than 64k sections,
+ * read count from .sh_size.
+ * note: it doesn't need shndx2secindex()
+ */
+ info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
+ }
+ else {
+ info->num_sections = hdr->e_shnum;
+ }
+ if (hdr->e_shstrndx == SHN_XINDEX) {
+ info->secindex_strings =
+ shndx2secindex(TO_NATIVE(sechdrs[0].sh_link));
+ }
+ else {
+ info->secindex_strings = hdr->e_shstrndx;
+ }
+
/* Fix endianness in section headers */
- for (i = 0; i < hdr->e_shnum; i++) {
+ for (i = 0; i < info->num_sections; i++) {
sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags);
@@ -431,9 +453,8 @@ static int parse_elf(struct elf_info *info, const char *filename)
sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize);
}
/* Find symbol table. */
- for (i = 1; i < hdr->e_shnum; i++) {
- const char *secstrings
- = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+ secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
+ for (i = 1; i < info->num_sections; i++) {
const char *secname;
int nobits = sechdrs[i].sh_type == SHT_NOBITS;
@@ -461,14 +482,26 @@ static int parse_elf(struct elf_info *info, const char *filename)
else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
info->export_gpl_future_sec = i;
- if (sechdrs[i].sh_type != SHT_SYMTAB)
- continue;
+ if (sechdrs[i].sh_type == SHT_SYMTAB) {
+ unsigned int sh_link_idx;
+ symtab_idx = i;
+ info->symtab_start = (void *)hdr +
+ sechdrs[i].sh_offset;
+ info->symtab_stop = (void *)hdr +
+ sechdrs[i].sh_offset + sechdrs[i].sh_size;
+ sh_link_idx = shndx2secindex(sechdrs[i].sh_link);
+ info->strtab = (void *)hdr +
+ sechdrs[sh_link_idx].sh_offset;
+ }
- info->symtab_start = (void *)hdr + sechdrs[i].sh_offset;
- info->symtab_stop = (void *)hdr + sechdrs[i].sh_offset
- + sechdrs[i].sh_size;
- info->strtab = (void *)hdr +
- sechdrs[sechdrs[i].sh_link].sh_offset;
+ /* 32bit section no. table? ("more than 64k sections") */
+ if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
+ symtab_shndx_idx = i;
+ info->symtab_shndx_start = (void *)hdr +
+ sechdrs[i].sh_offset;
+ info->symtab_shndx_stop = (void *)hdr +
+ sechdrs[i].sh_offset + sechdrs[i].sh_size;
+ }
}
if (!info->symtab_start)
fatal("%s has no symtab?\n", filename);
@@ -480,6 +513,21 @@ static int parse_elf(struct elf_info *info, const char *filename)
sym->st_value = TO_NATIVE(sym->st_value);
sym->st_size = TO_NATIVE(sym->st_size);
}
+
+ if (symtab_shndx_idx != ~0U) {
+ Elf32_Word *p;
+ if (symtab_idx !=
+ shndx2secindex(sechdrs[symtab_shndx_idx].sh_link))
+ fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
+ filename,
+ shndx2secindex(sechdrs[symtab_shndx_idx].sh_link),
+ symtab_idx);
+ /* Fix endianness */
+ for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
+ p++)
+ *p = TO_NATIVE(*p);
+ }
+
return 1;
}
@@ -503,6 +551,11 @@ static int ignore_undef_symbol(struct elf_info *info, const char *symname)
strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 ||
strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0)
return 1;
+ if (info->hdr->e_machine == EM_PPC64)
+ /* Special register function linked on all modules during final link of .ko */
+ if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 ||
+ strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0)
+ return 1;
/* Do not ignore this symbol */
return 0;
}
@@ -514,7 +567,7 @@ static void handle_modversions(struct module *mod, struct elf_info *info,
Elf_Sym *sym, const char *symname)
{
unsigned int crc;
- enum export export = export_from_sec(info, sym->st_shndx);
+ enum export export = export_from_sec(info, get_secindex(info, sym));
switch (sym->st_shndx) {
case SHN_COMMON:
@@ -656,19 +709,19 @@ static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
return "(unknown)";
}
-static const char *sec_name(struct elf_info *elf, int shndx)
+static const char *sec_name(struct elf_info *elf, int secindex)
{
Elf_Shdr *sechdrs = elf->sechdrs;
return (void *)elf->hdr +
- elf->sechdrs[elf->hdr->e_shstrndx].sh_offset +
- sechdrs[shndx].sh_name;
+ elf->sechdrs[elf->secindex_strings].sh_offset +
+ sechdrs[secindex].sh_name;
}
static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr)
{
return (void *)elf->hdr +
- elf->sechdrs[elf->hdr->e_shstrndx].sh_offset +
- sechdr->sh_name;
+ elf->sechdrs[elf->secindex_strings].sh_offset +
+ sechdr->sh_name;
}
/* if sym is empty or point to a string
@@ -737,6 +790,8 @@ static const char *section_white_list[] =
{
".comment*",
".debug*",
+ ".zdebug*", /* Compressed debug sections. */
+ ".GCC-command-line", /* mn10300 */
".mdebug*", /* alpha, score, mips etc. */
".pdr", /* alpha, score, mips etc. */
".stab*",
@@ -981,6 +1036,13 @@ static const struct sectioncheck *section_mismatch(
* fromsec = .data*
* atsym =__param*
*
+ * Pattern 1a:
+ * module_param_call() ops can refer to __init set function if permissions=0
+ * The pattern is identified by:
+ * tosec = .init.text
+ * fromsec = .data*
+ * atsym = __param_ops_*
+ *
* Pattern 2:
* Many drivers utilise a *driver container with references to
* add, remove, probe functions etc.
@@ -1015,6 +1077,12 @@ static int secref_whitelist(const struct sectioncheck *mismatch,
(strncmp(fromsym, "__param", strlen("__param")) == 0))
return 0;
+ /* Check for pattern 1a */
+ if (strcmp(tosec, ".init.text") == 0 &&
+ match(fromsec, data_sections) &&
+ (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0))
+ return 0;
+
/* Check for pattern 2 */
if (match(tosec, init_exit_sections) &&
match(fromsec, data_sections) &&
@@ -1047,11 +1115,14 @@ static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
Elf_Sym *near = NULL;
Elf64_Sword distance = 20;
Elf64_Sword d;
+ unsigned int relsym_secindex;
if (relsym->st_name != 0)
return relsym;
+
+ relsym_secindex = get_secindex(elf, relsym);
for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
- if (sym->st_shndx != relsym->st_shndx)
+ if (get_secindex(elf, sym) != relsym_secindex)
continue;
if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
continue;
@@ -1113,9 +1184,9 @@ static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
const char *symsec;
- if (sym->st_shndx >= SHN_LORESERVE)
+ if (is_shndx_special(sym->st_shndx))
continue;
- symsec = sec_name(elf, sym->st_shndx);
+ symsec = sec_name(elf, get_secindex(elf, sym));
if (strcmp(symsec, sec) != 0)
continue;
if (!is_valid_name(elf, sym))
@@ -1138,6 +1209,9 @@ static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
* .cpuinit.data => __cpudata
* .memexitconst => __memconst
* etc.
+ *
+ * The memory of returned value has been allocated on a heap. The user of this
+ * method should free it after usage.
*/
static char *sec2annotation(const char *s)
{
@@ -1160,9 +1234,9 @@ static char *sec2annotation(const char *s)
strcat(p, "data ");
else
strcat(p, " ");
- return r; /* we leak her but we do not care */
+ return r;
} else {
- return "";
+ return strdup("");
}
}
@@ -1190,6 +1264,8 @@ static void report_sec_mismatch(const char *modname,
{
const char *from, *from_p;
const char *to, *to_p;
+ char *prl_from;
+ char *prl_to;
switch (from_is_func) {
case 0: from = "variable"; from_p = ""; break;
@@ -1213,16 +1289,21 @@ static void report_sec_mismatch(const char *modname,
switch (mismatch->mismatch) {
case TEXT_TO_ANY_INIT:
+ prl_from = sec2annotation(fromsec);
+ prl_to = sec2annotation(tosec);
fprintf(stderr,
"The function %s%s() references\n"
"the %s %s%s%s.\n"
"This is often because %s lacks a %s\n"
"annotation or the annotation of %s is wrong.\n",
- sec2annotation(fromsec), fromsym,
- to, sec2annotation(tosec), tosym, to_p,
- fromsym, sec2annotation(tosec), tosym);
+ prl_from, fromsym,
+ to, prl_to, tosym, to_p,
+ fromsym, prl_to, tosym);
+ free(prl_from);
+ free(prl_to);
break;
case DATA_TO_ANY_INIT: {
+ prl_to = sec2annotation(tosec);
const char *const *s = mismatch->symbol_white_list;
fprintf(stderr,
"The variable %s references\n"
@@ -1230,20 +1311,24 @@ static void report_sec_mismatch(const char *modname,
"If the reference is valid then annotate the\n"
"variable with __init* or __refdata (see linux/init.h) "
"or name the variable:\n",
- fromsym, to, sec2annotation(tosec), tosym, to_p);
+ fromsym, to, prl_to, tosym, to_p);
while (*s)
fprintf(stderr, "%s, ", *s++);
fprintf(stderr, "\n");
+ free(prl_to);
break;
}
case TEXT_TO_ANY_EXIT:
+ prl_to = sec2annotation(tosec);
fprintf(stderr,
"The function %s() references a %s in an exit section.\n"
"Often the %s %s%s has valid usage outside the exit section\n"
"and the fix is to remove the %sannotation of %s.\n",
- fromsym, to, to, tosym, to_p, sec2annotation(tosec), tosym);
+ fromsym, to, to, tosym, to_p, prl_to, tosym);
+ free(prl_to);
break;
case DATA_TO_ANY_EXIT: {
+ prl_to = sec2annotation(tosec);
const char *const *s = mismatch->symbol_white_list;
fprintf(stderr,
"The variable %s references\n"
@@ -1251,24 +1336,31 @@ static void report_sec_mismatch(const char *modname,
"If the reference is valid then annotate the\n"
"variable with __exit* (see linux/init.h) or "
"name the variable:\n",
- fromsym, to, sec2annotation(tosec), tosym, to_p);
+ fromsym, to, prl_to, tosym, to_p);
while (*s)
fprintf(stderr, "%s, ", *s++);
fprintf(stderr, "\n");
+ free(prl_to);
break;
}
case XXXINIT_TO_SOME_INIT:
case XXXEXIT_TO_SOME_EXIT:
+ prl_from = sec2annotation(fromsec);
+ prl_to = sec2annotation(tosec);
fprintf(stderr,
"The %s %s%s%s references\n"
"a %s %s%s%s.\n"
"If %s is only used by %s then\n"
"annotate %s with a matching annotation.\n",
- from, sec2annotation(fromsec), fromsym, from_p,
- to, sec2annotation(tosec), tosym, to_p,
+ from, prl_from, fromsym, from_p,
+ to, prl_to, tosym, to_p,
tosym, fromsym, tosym);
+ free(prl_from);
+ free(prl_to);
break;
case ANY_INIT_TO_ANY_EXIT:
+ prl_from = sec2annotation(fromsec);
+ prl_to = sec2annotation(tosec);
fprintf(stderr,
"The %s %s%s%s references\n"
"a %s %s%s%s.\n"
@@ -1277,11 +1369,15 @@ static void report_sec_mismatch(const char *modname,
"uses functionality in the exit path.\n"
"The fix is often to remove the %sannotation of\n"
"%s%s so it may be used outside an exit section.\n",
- from, sec2annotation(fromsec), fromsym, from_p,
- to, sec2annotation(tosec), tosym, to_p,
- sec2annotation(tosec), tosym, to_p);
+ from, prl_from, fromsym, from_p,
+ to, prl_to, tosym, to_p,
+ prl_to, tosym, to_p);
+ free(prl_from);
+ free(prl_to);
break;
case ANY_EXIT_TO_ANY_INIT:
+ prl_from = sec2annotation(fromsec);
+ prl_to = sec2annotation(tosec);
fprintf(stderr,
"The %s %s%s%s references\n"
"a %s %s%s%s.\n"
@@ -1290,16 +1386,20 @@ static void report_sec_mismatch(const char *modname,
"uses functionality in the init path.\n"
"The fix is often to remove the %sannotation of\n"
"%s%s so it may be used outside an init section.\n",
- from, sec2annotation(fromsec), fromsym, from_p,
- to, sec2annotation(tosec), tosym, to_p,
- sec2annotation(tosec), tosym, to_p);
+ from, prl_from, fromsym, from_p,
+ to, prl_to, tosym, to_p,
+ prl_to, tosym, to_p);
+ free(prl_from);
+ free(prl_to);
break;
case EXPORT_TO_INIT_EXIT:
+ prl_to = sec2annotation(tosec);
fprintf(stderr,
"The symbol %s is exported and annotated %s\n"
"Fix this by removing the %sannotation of %s "
"or drop the export.\n",
- tosym, sec2annotation(tosec), sec2annotation(tosec), tosym);
+ tosym, prl_to, prl_to, tosym);
+ free(prl_to);
break;
}
fprintf(stderr, "\n");
@@ -1311,7 +1411,7 @@ static void check_section_mismatch(const char *modname, struct elf_info *elf,
const char *tosec;
const struct sectioncheck *mismatch;
- tosec = sec_name(elf, sym->st_shndx);
+ tosec = sec_name(elf, get_secindex(elf, sym));
mismatch = section_mismatch(fromsec, tosec);
if (mismatch) {
Elf_Sym *to;
@@ -1339,10 +1439,10 @@ static unsigned int *reloc_location(struct elf_info *elf,
Elf_Shdr *sechdr, Elf_Rela *r)
{
Elf_Shdr *sechdrs = elf->sechdrs;
- int section = sechdr->sh_info;
+ int section = shndx2secindex(sechdr->sh_info);
return (void *)elf->hdr + sechdrs[section].sh_offset +
- (r->r_offset - sechdrs[section].sh_addr);
+ r->r_offset;
}
static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
@@ -1447,7 +1547,7 @@ static void section_rela(const char *modname, struct elf_info *elf,
r.r_addend = TO_NATIVE(rela->r_addend);
sym = elf->symtab_start + r_sym;
/* Skip special sections */
- if (sym->st_shndx >= SHN_LORESERVE)
+ if (is_shndx_special(sym->st_shndx))
continue;
check_section_mismatch(modname, elf, &r, sym, fromsec);
}
@@ -1505,7 +1605,7 @@ static void section_rel(const char *modname, struct elf_info *elf,
}
sym = elf->symtab_start + r_sym;
/* Skip special sections */
- if (sym->st_shndx >= SHN_LORESERVE)
+ if (is_shndx_special(sym->st_shndx))
continue;
check_section_mismatch(modname, elf, &r, sym, fromsec);
}
@@ -1530,7 +1630,7 @@ static void check_sec_ref(struct module *mod, const char *modname,
Elf_Shdr *sechdrs = elf->sechdrs;
/* Walk through all sections */
- for (i = 0; i < elf->hdr->e_shnum; i++) {
+ for (i = 0; i < elf->num_sections; i++) {
check_section(modname, elf, &elf->sechdrs[i]);
/* We want to process only relocation sections and not .init */
if (sechdrs[i].sh_type == SHT_RELA)
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.