{
Elf_Shdr *sechdr = &info->sechdrs[secindex];
- if (info->hdr->e_type != ET_REL)
- offset -= sechdr->sh_addr;
-
return (void *)info->hdr + sechdr->sh_offset + offset;
}
-static void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym)
+void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym)
{
return sym_get_data_by_offset(info, get_secindex(info, sym),
sym->st_value);
sechdr->sh_name);
}
-static const char *sec_name(const struct elf_info *info, int secindex)
+static const char *sec_name(const struct elf_info *info, unsigned int secindex)
{
+ /*
+ * If sym->st_shndx is a special section index, there is no
+ * corresponding section header.
+ * Return "" if the index is out of range of info->sechdrs[] array.
+ */
+ if (secindex >= info->num_sections)
+ return "";
+
return sech_name(info, &info->sechdrs[secindex]);
}
sechdrs = (void *)hdr + hdr->e_shoff;
info->sechdrs = sechdrs;
+ /* modpost only works for relocatable objects */
+ if (hdr->e_type != ET_REL)
+ fatal("%s: not relocatable object.", filename);
+
/* Check if file offset is correct */
if (hdr->e_shoff > info->size) {
fatal("section header offset=%lu in file '%s' is bigger than filesize=%zu\n",
return false;
}
+/* useful to pass patterns to match() directly */
+#define PATTERNS(...) \
+ ({ \
+ static const char *const patterns[] = {__VA_ARGS__, NULL}; \
+ patterns; \
+ })
+
/* sections that we do not want to do full section mismatch check on */
static const char *const section_white_list[] =
{
".comment*",
".debug*",
- ".cranges", /* sh64 */
".zdebug*", /* Compressed debug sections. */
".GCC.command.line", /* record-gcc-switches */
".mdebug*", /* alpha, score, mips etc. */
/* all init sections */
static const char *const init_sections[] = { ALL_INIT_SECTIONS, NULL };
-/* All init and exit sections (code + data) */
-static const char *const init_exit_sections[] =
- {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
-
/* all text sections */
static const char *const text_sections[] = { ALL_TEXT_SECTIONS, NULL };
/* data section */
static const char *const data_sections[] = { DATA_SECTIONS, NULL };
-
-/* symbols in .data that may refer to init/exit sections */
-#define DEFAULT_SYMBOL_WHITE_LIST \
- "*driver", \
- "*_template", /* scsi uses *_template a lot */ \
- "*_timer", /* arm uses ops structures named _timer a lot */ \
- "*_sht", /* scsi also used *_sht to some extent */ \
- "*_ops", \
- "*_probe", \
- "*_probe_one", \
- "*_console"
-
static const char *const head_sections[] = { ".head.text*", NULL };
static const char *const linker_symbols[] =
{ "__init_begin", "_sinittext", "_einittext", NULL };
*
* @mismatch: Type of mismatch.
*
- * @symbol_white_list: Do not match a relocation to a symbol in this list
- * even if it is targeting a section in @bad_to_sec.
- *
* @handler: Specific handler to call when a match is found. If NULL,
* default_mismatch_handler() will be called.
*
const char *bad_tosec[20];
const char *good_tosec[20];
enum mismatch mismatch;
- const char *symbol_white_list[20];
void (*handler)(const char *modname, struct elf_info *elf,
const struct sectioncheck* const mismatch,
Elf_Rela *r, Elf_Sym *sym, const char *fromsec);
.fromsec = { TEXT_SECTIONS, NULL },
.bad_tosec = { ALL_INIT_SECTIONS, NULL },
.mismatch = TEXT_TO_ANY_INIT,
- .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
{
.fromsec = { DATA_SECTIONS, NULL },
.bad_tosec = { ALL_XXXINIT_SECTIONS, NULL },
.mismatch = DATA_TO_ANY_INIT,
- .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
{
.fromsec = { DATA_SECTIONS, NULL },
.bad_tosec = { INIT_SECTIONS, NULL },
.mismatch = DATA_TO_ANY_INIT,
- .symbol_white_list = {
- "*_template", "*_timer", "*_sht", "*_ops",
- "*_probe", "*_probe_one", "*_console", NULL
- },
},
{
.fromsec = { TEXT_SECTIONS, NULL },
.bad_tosec = { ALL_EXIT_SECTIONS, NULL },
.mismatch = TEXT_TO_ANY_EXIT,
- .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
{
.fromsec = { DATA_SECTIONS, NULL },
.bad_tosec = { ALL_EXIT_SECTIONS, NULL },
.mismatch = DATA_TO_ANY_EXIT,
- .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
/* Do not reference init code/data from meminit code/data */
{
.fromsec = { ALL_XXXINIT_SECTIONS, NULL },
.bad_tosec = { INIT_SECTIONS, NULL },
.mismatch = XXXINIT_TO_SOME_INIT,
- .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
/* Do not reference exit code/data from memexit code/data */
{
.fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
.bad_tosec = { EXIT_SECTIONS, NULL },
.mismatch = XXXEXIT_TO_SOME_EXIT,
- .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
/* Do not use exit code/data from init code */
{
.fromsec = { ALL_INIT_SECTIONS, NULL },
.bad_tosec = { ALL_EXIT_SECTIONS, NULL },
.mismatch = ANY_INIT_TO_ANY_EXIT,
- .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
/* Do not use init code/data from exit code */
{
.fromsec = { ALL_EXIT_SECTIONS, NULL },
.bad_tosec = { ALL_INIT_SECTIONS, NULL },
.mismatch = ANY_EXIT_TO_ANY_INIT,
- .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
{
.fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
.bad_tosec = { INIT_SECTIONS, NULL },
.mismatch = ANY_INIT_TO_ANY_EXIT,
- .symbol_white_list = { NULL },
},
/* Do not export init/exit functions or data */
{
.fromsec = { "___ksymtab*", NULL },
.bad_tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
.mismatch = EXPORT_TO_INIT_EXIT,
- .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
{
.fromsec = { "__ex_table", NULL },
* fromsec = .data*
* atsym = __param_ops_*
*
- * Pattern 2:
- * Many drivers utilise a *driver container with references to
- * add, remove, probe functions etc.
- * the pattern is identified by:
- * tosec = init or exit section
- * fromsec = data section
- * atsym = *driver, *_template, *_sht, *_ops, *_probe,
- * *probe_one, *_console, *_timer
- *
* Pattern 3:
* Whitelist all references from .head.text to any init section
*
strstarts(fromsym, "__param_ops_"))
return 0;
- /* Check for pattern 2 */
- if (match(tosec, init_exit_sections) &&
- match(fromsec, data_sections) &&
- match(fromsym, mismatch->symbol_white_list))
+ /* symbols in data sections that may refer to any init/exit sections */
+ if (match(fromsec, PATTERNS(DATA_SECTIONS)) &&
+ match(tosec, PATTERNS(ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS)) &&
+ match(fromsym, PATTERNS("*_template", // scsi uses *_template a lot
+ "*_timer", // arm uses ops structures named _timer a lot
+ "*_sht", // scsi also used *_sht to some extent
+ "*_ops",
+ "*_probe",
+ "*_probe_one",
+ "*_console")))
+ return 0;
+
+ /* symbols in data sections that may refer to meminit/exit sections */
+ if (match(fromsec, PATTERNS(DATA_SECTIONS)) &&
+ match(tosec, PATTERNS(ALL_XXXINIT_SECTIONS, ALL_EXIT_SECTIONS)) &&
+ match(fromsym, PATTERNS("*driver")))
return 0;
/* Check for pattern 3 */
return near;
}
-/*
- * Convert a section name to the function/data attribute
- * .init.text => __init
- * .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)
-{
- if (match(s, init_exit_sections)) {
- char *p = NOFAIL(malloc(20));
- char *r = p;
-
- *p++ = '_';
- *p++ = '_';
- if (*s == '.')
- s++;
- while (*s && *s != '.')
- *p++ = *s++;
- *p = '\0';
- if (*s == '.')
- s++;
- if (strstr(s, "rodata") != NULL)
- strcat(p, "const ");
- else if (strstr(s, "data") != NULL)
- strcat(p, "data ");
- else
- strcat(p, " ");
- return r;
- } else {
- return NOFAIL(strdup(""));
- }
-}
-
static int is_function(Elf_Sym *sym)
{
if (sym)
return -1;
}
-static void print_section_list(const char * const list[20])
-{
- const char *const *s = list;
-
- while (*s) {
- fprintf(stderr, "%s", *s);
- s++;
- if (*s)
- fprintf(stderr, ", ");
- }
- fprintf(stderr, "\n");
-}
-
static inline void get_pretty_name(int is_func, const char** name, const char** name_p)
{
switch (is_func) {
static void report_sec_mismatch(const char *modname,
const struct sectioncheck *mismatch,
const char *fromsec,
- unsigned long long fromaddr,
const char *fromsym,
- int from_is_func,
- const char *tosec, const char *tosym,
- int to_is_func)
+ const char *tosec, const char *tosym)
{
- const char *from, *from_p;
- const char *to, *to_p;
- char *prl_from;
- char *prl_to;
-
sec_mismatch_count++;
- get_pretty_name(from_is_func, &from, &from_p);
- get_pretty_name(to_is_func, &to, &to_p);
-
- warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
- "to the %s %s:%s%s\n",
- modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec,
- tosym, to_p);
-
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",
- 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);
- fprintf(stderr,
- "The variable %s references\n"
- "the %s %s%s%s\n"
- "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, prl_to, tosym, to_p);
- print_section_list(mismatch->symbol_white_list);
- free(prl_to);
- break;
- }
+ case DATA_TO_ANY_INIT:
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, prl_to, tosym);
- free(prl_to);
- break;
- case DATA_TO_ANY_EXIT: {
- prl_to = sec2annotation(tosec);
- fprintf(stderr,
- "The variable %s references\n"
- "the %s %s%s%s\n"
- "If the reference is valid then annotate the\n"
- "variable with __exit* (see linux/init.h) or "
- "name the variable:\n",
- fromsym, to, prl_to, tosym, to_p);
- print_section_list(mismatch->symbol_white_list);
- free(prl_to);
- break;
- }
+ case DATA_TO_ANY_EXIT:
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, 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"
- "This is often seen when error handling "
- "in the init function\n"
- "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, 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"
- "This is often seen when error handling "
- "in the exit function\n"
- "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, prl_from, fromsym, from_p,
- to, prl_to, tosym, to_p,
- prl_to, tosym, to_p);
- free(prl_from);
- free(prl_to);
+ warn("%s: section mismatch in reference: %s (section: %s) -> %s (section: %s)\n",
+ modname, fromsym, fromsec, tosym, tosec);
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, prl_to, prl_to, tosym);
- free(prl_to);
+ warn("%s: EXPORT_SYMBOL used for init/exit symbol: %s (section: %s)\n",
+ modname, tosym, tosec);
break;
case EXTABLE_TO_NON_TEXT:
- fatal("There's a special handler for this mismatch type, "
- "we should never get here.");
+ fatal("There's a special handler for this mismatch type, we should never get here.\n");
break;
}
- fprintf(stderr, "\n");
}
static void default_mismatch_handler(const char *modname, struct elf_info *elf,
from = find_elf_symbol2(elf, r->r_offset, fromsec);
fromsym = sym_name(elf, from);
- if (strstarts(fromsym, "reference___initcall"))
- return;
-
tosec = sec_name(elf, get_secindex(elf, sym));
to = find_elf_symbol(elf, r->r_addend, sym);
tosym = sym_name(elf, to);
if (secref_whitelist(mismatch,
fromsec, fromsym, tosec, tosym)) {
report_sec_mismatch(modname, mismatch,
- fromsec, r->r_offset, fromsym,
- is_function(from), tosec, tosym,
- is_function(to));
+ fromsec, fromsym, tosec, tosym);
}
}
break;
case R_386_PC32:
r->r_addend = TO_NATIVE(*location) + 4;
- /* For CONFIG_RELOCATABLE=y */
- if (elf->hdr->e_type == ET_EXEC)
- r->r_addend += r->r_offset;
break;
}
return 0;
Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
Elf_Rela *stop = (void *)start + sechdr->sh_size;
- fromsec = sech_name(elf, sechdr);
- fromsec += strlen(".rela");
+ fromsec = sec_name(elf, sechdr->sh_info);
/* if from section (name) is know good then skip it */
if (match(fromsec, section_white_list))
return;
Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
Elf_Rel *stop = (void *)start + sechdr->sh_size;
- fromsec = sech_name(elf, sechdr);
- fromsec += strlen(".rel");
+ fromsec = sec_name(elf, sechdr->sh_info);
/* if from section (name) is know good then skip it */
if (match(fromsec, section_white_list))
return;
projects / linux-2.6-microblaze.git / blobdiff