static int sec_mismatch_count;
static bool sec_mismatch_warn_only = true;
+/* Trim EXPORT_SYMBOLs that are unused by in-tree modules */
+static bool trim_unused_exports;
+
/* ignore missing files */
static bool ignore_missing_files;
/* If set to 1, only warn (instead of error) about missing ns imports */
static bool error_occurred;
+static bool extra_warn;
+
/*
* Cut off the warnings when there are too many. This typically occurs when
* vmlinux is missing. ('make modules' without building vmlinux.)
unsigned int crc;
bool crc_valid;
bool weak;
+ bool is_func;
bool is_gpl_only; /* exported by EXPORT_SYMBOL_GPL */
+ bool used; /* there exists a user of this symbol */
char name[];
};
{
struct namespace_list *list;
+ /*
+ * The default namespace is null string "", which is always implicitly
+ * contained.
+ */
+ if (!namespace[0])
+ return true;
+
list_for_each_entry(list, head, list) {
if (!strcmp(list->namespace, namespace))
return true;
#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
-static void sym_update_namespace(const char *symname, const char *namespace)
-{
- struct symbol *s = find_symbol(symname);
-
- /*
- * That symbol should have been created earlier and thus this is
- * actually an assertion.
- */
- if (!s) {
- error("Could not update namespace(%s) for symbol %s\n",
- namespace, symname);
- return;
- }
-
- free(s->namespace);
- s->namespace = namespace[0] ? NOFAIL(strdup(namespace)) : NULL;
-}
-
static struct symbol *sym_add_exported(const char *name, struct module *mod,
- bool gpl_only)
+ bool gpl_only, const char *namespace)
{
struct symbol *s = find_symbol(name);
s = alloc_symbol(name);
s->module = mod;
s->is_gpl_only = gpl_only;
+ s->namespace = NOFAIL(strdup(namespace));
list_add_tail(&s->list, &mod->exported_symbols);
hash_add_symbol(s);
fatal("%s has NOBITS .modinfo\n", filename);
info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
info->modinfo_len = sechdrs[i].sh_size;
+ } else if (!strcmp(secname, ".export_symbol")) {
+ info->export_symbol_secndx = i;
}
if (sechdrs[i].sh_type == SHT_SYMTAB) {
ELF_ST_BIND(sym->st_info) == STB_WEAK);
break;
default:
- /* All exported symbols */
- if (strstarts(symname, "__ksymtab_")) {
- const char *name, *secname;
-
- name = symname + strlen("__ksymtab_");
- secname = sec_name(info, get_secindex(info, sym));
-
- if (strstarts(secname, "___ksymtab_gpl+"))
- sym_add_exported(name, mod, true);
- else if (strstarts(secname, "___ksymtab+"))
- sym_add_exported(name, mod, false);
- }
if (strcmp(symname, "init_module") == 0)
mod->has_init = true;
if (strcmp(symname, "cleanup_module") == 0)
#define ALL_TEXT_SECTIONS ALL_INIT_TEXT_SECTIONS, ALL_EXIT_TEXT_SECTIONS, \
TEXT_SECTIONS, OTHER_TEXT_SECTIONS
-/* init data sections */
-static const char *const init_data_sections[] =
- { ALL_INIT_DATA_SECTIONS, NULL };
-
-/* all init sections */
-static const char *const init_sections[] = { ALL_INIT_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 };
-
-static const char *const head_sections[] = { ".head.text*", NULL };
-static const char *const linker_symbols[] =
- { "__init_begin", "_sinittext", "_einittext", NULL };
-static const char *const optim_symbols[] = { "*.constprop.*", NULL };
-
enum mismatch {
TEXT_TO_ANY_INIT,
DATA_TO_ANY_INIT,
- TEXT_TO_ANY_EXIT,
- DATA_TO_ANY_EXIT,
+ TEXTDATA_TO_ANY_EXIT,
XXXINIT_TO_SOME_INIT,
XXXEXIT_TO_SOME_EXIT,
ANY_INIT_TO_ANY_EXIT,
ANY_EXIT_TO_ANY_INIT,
- EXPORT_TO_INIT_EXIT,
EXTABLE_TO_NON_TEXT,
};
* targeting sections in this array (white-list). Can be empty.
*
* @mismatch: Type of mismatch.
- *
- * @handler: Specific handler to call when a match is found. If NULL,
- * default_mismatch_handler() will be called.
- *
*/
struct sectioncheck {
const char *fromsec[20];
const char *bad_tosec[20];
const char *good_tosec[20];
enum mismatch mismatch;
- void (*handler)(const char *modname, struct elf_info *elf,
- const struct sectioncheck* const mismatch,
- Elf_Rela *r, Elf_Sym *sym, const char *fromsec);
-
};
-static void extable_mismatch_handler(const char *modname, struct elf_info *elf,
- const struct sectioncheck* const mismatch,
- Elf_Rela *r, Elf_Sym *sym,
- const char *fromsec);
-
static const struct sectioncheck sectioncheck[] = {
/* Do not reference init/exit code/data from
* normal code and data
},
{
.fromsec = { DATA_SECTIONS, NULL },
- .bad_tosec = { ALL_XXXINIT_SECTIONS, NULL },
- .mismatch = DATA_TO_ANY_INIT,
-},
-{
- .fromsec = { DATA_SECTIONS, NULL },
- .bad_tosec = { INIT_SECTIONS, NULL },
+ .bad_tosec = { ALL_XXXINIT_SECTIONS, INIT_SECTIONS, NULL },
.mismatch = DATA_TO_ANY_INIT,
},
{
- .fromsec = { TEXT_SECTIONS, NULL },
- .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
- .mismatch = TEXT_TO_ANY_EXIT,
-},
-{
- .fromsec = { DATA_SECTIONS, NULL },
+ .fromsec = { TEXT_SECTIONS, DATA_SECTIONS, NULL },
.bad_tosec = { ALL_EXIT_SECTIONS, NULL },
- .mismatch = DATA_TO_ANY_EXIT,
+ .mismatch = TEXTDATA_TO_ANY_EXIT,
},
/* Do not reference init code/data from meminit code/data */
{
.bad_tosec = { INIT_SECTIONS, NULL },
.mismatch = ANY_INIT_TO_ANY_EXIT,
},
-/* Do not export init/exit functions or data */
-{
- .fromsec = { "___ksymtab*", NULL },
- .bad_tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
- .mismatch = EXPORT_TO_INIT_EXIT,
-},
{
.fromsec = { "__ex_table", NULL },
/* If you're adding any new black-listed sections in here, consider
.bad_tosec = { ".altinstr_replacement", NULL },
.good_tosec = {ALL_TEXT_SECTIONS , NULL},
.mismatch = EXTABLE_TO_NON_TEXT,
- .handler = extable_mismatch_handler,
}
};
* fromsec = text section
* refsymname = *.constprop.*
*
- * Pattern 6:
- * Hide section mismatch warnings for ELF local symbols. The goal
- * is to eliminate false positive modpost warnings caused by
- * compiler-generated ELF local symbol names such as ".LANCHOR1".
- * Autogenerated symbol names bypass modpost's "Pattern 2"
- * whitelisting, which relies on pattern-matching against symbol
- * names to work. (One situation where gcc can autogenerate ELF
- * local symbols is when "-fsection-anchors" is used.)
**/
-static int secref_whitelist(const struct sectioncheck *mismatch,
- const char *fromsec, const char *fromsym,
+static int secref_whitelist(const char *fromsec, const char *fromsym,
const char *tosec, const char *tosym)
{
/* Check for pattern 1 */
- if (match(tosec, init_data_sections) &&
- match(fromsec, data_sections) &&
+ if (match(tosec, PATTERNS(ALL_INIT_DATA_SECTIONS)) &&
+ match(fromsec, PATTERNS(DATA_SECTIONS)) &&
strstarts(fromsym, "__param"))
return 0;
/* Check for pattern 1a */
if (strcmp(tosec, ".init.text") == 0 &&
- match(fromsec, data_sections) &&
+ match(fromsec, PATTERNS(DATA_SECTIONS)) &&
strstarts(fromsym, "__param_ops_"))
return 0;
return 0;
/* Check for pattern 3 */
- if (match(fromsec, head_sections) &&
- match(tosec, init_sections))
+ if (strstarts(fromsec, ".head.text") &&
+ match(tosec, PATTERNS(ALL_INIT_SECTIONS)))
return 0;
/* Check for pattern 4 */
- if (match(tosym, linker_symbols))
+ if (match(tosym, PATTERNS("__init_begin", "_sinittext", "_einittext")))
return 0;
/* Check for pattern 5 */
- if (match(fromsec, text_sections) &&
- match(tosec, init_sections) &&
- match(fromsym, optim_symbols))
- return 0;
-
- /* Check for pattern 6 */
- if (strstarts(fromsym, ".L"))
+ if (match(fromsec, PATTERNS(ALL_TEXT_SECTIONS)) &&
+ match(tosec, PATTERNS(ALL_INIT_SECTIONS)) &&
+ match(fromsym, PATTERNS("*.constprop.*")))
return 0;
return 1;
return !is_mapping_symbol(name);
}
-/**
- * Find symbol based on relocation record info.
- * In some cases the symbol supplied is a valid symbol so
- * return refsym. If st_name != 0 we assume this is a valid symbol.
- * In other cases the symbol needs to be looked up in the symbol table
- * based on section and address.
- * **/
-static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
- Elf_Sym *relsym)
+/* Look up the nearest symbol based on the section and the address */
+static Elf_Sym *find_nearest_sym(struct elf_info *elf, Elf_Addr addr,
+ unsigned int secndx, bool allow_negative,
+ Elf_Addr min_distance)
{
Elf_Sym *sym;
Elf_Sym *near = NULL;
- Elf64_Sword distance = 20;
- Elf64_Sword d;
- unsigned int relsym_secindex;
-
- if (relsym->st_name != 0)
- return relsym;
+ Elf_Addr sym_addr, distance;
+ bool is_arm = (elf->hdr->e_machine == EM_ARM);
- relsym_secindex = get_secindex(elf, relsym);
for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
- if (get_secindex(elf, sym) != relsym_secindex)
- continue;
- if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
+ if (get_secindex(elf, sym) != secndx)
continue;
if (!is_valid_name(elf, sym))
continue;
- if (sym->st_value == addr)
- return sym;
- /* Find a symbol nearby - addr are maybe negative */
- d = sym->st_value - addr;
- if (d < 0)
- d = addr - sym->st_value;
- if (d < distance) {
- distance = d;
- near = sym;
- }
- }
- /* We need a close match */
- if (distance < 20)
- return near;
- else
- return NULL;
-}
-/*
- * Find symbols before or equal addr and after addr - in the section sec.
- * If we find two symbols with equal offset prefer one with a valid name.
- * The ELF format may have a better way to detect what type of symbol
- * it is, but this works for now.
- **/
-static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
- const char *sec)
-{
- Elf_Sym *sym;
- Elf_Sym *near = NULL;
- Elf_Addr distance = ~0;
+ sym_addr = sym->st_value;
- for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
- const char *symsec;
+ /*
+ * For ARM Thumb instruction, the bit 0 of st_value is set
+ * if the symbol is STT_FUNC type. Mask it to get the address.
+ */
+ if (is_arm && ELF_ST_TYPE(sym->st_info) == STT_FUNC)
+ sym_addr &= ~1;
- if (is_shndx_special(sym->st_shndx))
- continue;
- symsec = sec_name(elf, get_secindex(elf, sym));
- if (strcmp(symsec, sec) != 0)
- continue;
- if (!is_valid_name(elf, sym))
+ if (addr >= sym_addr)
+ distance = addr - sym_addr;
+ else if (allow_negative)
+ distance = sym_addr - addr;
+ else
continue;
- if (sym->st_value <= addr && addr - sym->st_value <= distance) {
- distance = addr - sym->st_value;
+
+ if (distance <= min_distance) {
+ min_distance = distance;
near = sym;
}
+
+ if (min_distance == 0)
+ break;
}
return near;
}
-static int is_function(Elf_Sym *sym)
+static Elf_Sym *find_fromsym(struct elf_info *elf, Elf_Addr addr,
+ unsigned int secndx)
{
- if (sym)
- return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
- else
- return -1;
+ return find_nearest_sym(elf, addr, secndx, false, ~0);
}
-static inline void get_pretty_name(int is_func, const char** name, const char** name_p)
+static Elf_Sym *find_tosym(struct elf_info *elf, Elf_Addr addr, Elf_Sym *sym)
{
- switch (is_func) {
- case 0: *name = "variable"; *name_p = ""; break;
- case 1: *name = "function"; *name_p = "()"; break;
- default: *name = "(unknown reference)"; *name_p = ""; break;
- }
+ /* If the supplied symbol has a valid name, return it */
+ if (is_valid_name(elf, sym))
+ return sym;
+
+ /*
+ * Strive to find a better symbol name, but the resulting name may not
+ * match the symbol referenced in the original code.
+ */
+ return find_nearest_sym(elf, addr, get_secindex(elf, sym), true, 20);
}
-/*
- * Print a warning about a section mismatch.
- * Try to find symbols near it so user can find it.
- * Check whitelist before warning - it may be a false positive.
- */
-static void report_sec_mismatch(const char *modname,
- const struct sectioncheck *mismatch,
- const char *fromsec,
- const char *fromsym,
- const char *tosec, const char *tosym)
+static bool is_executable_section(struct elf_info *elf, unsigned int secndx)
{
- sec_mismatch_count++;
+ if (secndx >= elf->num_sections)
+ return false;
- switch (mismatch->mismatch) {
- case TEXT_TO_ANY_INIT:
- case DATA_TO_ANY_INIT:
- case TEXT_TO_ANY_EXIT:
- case DATA_TO_ANY_EXIT:
- case XXXINIT_TO_SOME_INIT:
- case XXXEXIT_TO_SOME_EXIT:
- case ANY_INIT_TO_ANY_EXIT:
- case ANY_EXIT_TO_ANY_INIT:
- warn("%s: section mismatch in reference: %s (section: %s) -> %s (section: %s)\n",
- modname, fromsym, fromsec, tosym, tosec);
- break;
- case EXPORT_TO_INIT_EXIT:
- 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.\n");
- break;
- }
+ return (elf->sechdrs[secndx].sh_flags & SHF_EXECINSTR) != 0;
}
static void default_mismatch_handler(const char *modname, struct elf_info *elf,
const struct sectioncheck* const mismatch,
- Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
+ Elf_Sym *tsym,
+ unsigned int fsecndx, const char *fromsec, Elf_Addr faddr,
+ const char *tosec, Elf_Addr taddr)
{
- const char *tosec;
- Elf_Sym *to;
Elf_Sym *from;
const char *tosym;
const char *fromsym;
- from = find_elf_symbol2(elf, r->r_offset, fromsec);
+ from = find_fromsym(elf, faddr, fsecndx);
fromsym = sym_name(elf, from);
- tosec = sec_name(elf, get_secindex(elf, sym));
- to = find_elf_symbol(elf, r->r_addend, sym);
- tosym = sym_name(elf, to);
+ tsym = find_tosym(elf, taddr, tsym);
+ tosym = sym_name(elf, tsym);
/* check whitelist - we may ignore it */
- if (secref_whitelist(mismatch,
- fromsec, fromsym, tosec, tosym)) {
- report_sec_mismatch(modname, mismatch,
- fromsec, fromsym, tosec, tosym);
+ if (!secref_whitelist(fromsec, fromsym, tosec, tosym))
+ return;
+
+ sec_mismatch_count++;
+
+ warn("%s: section mismatch in reference: %s+0x%x (section: %s) -> %s (section: %s)\n",
+ modname, fromsym, (unsigned int)(faddr - from->st_value), fromsec, tosym, tosec);
+
+ if (mismatch->mismatch == EXTABLE_TO_NON_TEXT) {
+ if (match(tosec, mismatch->bad_tosec))
+ fatal("The relocation at %s+0x%lx references\n"
+ "section \"%s\" which is black-listed.\n"
+ "Something is seriously wrong and should be fixed.\n"
+ "You might get more information about where this is\n"
+ "coming from by using scripts/check_extable.sh %s\n",
+ fromsec, (long)faddr, tosec, modname);
+ else if (is_executable_section(elf, get_secindex(elf, tsym)))
+ warn("The relocation at %s+0x%lx references\n"
+ "section \"%s\" which is not in the list of\n"
+ "authorized sections. If you're adding a new section\n"
+ "and/or if this reference is valid, add \"%s\" to the\n"
+ "list of authorized sections to jump to on fault.\n"
+ "This can be achieved by adding \"%s\" to\n"
+ "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n",
+ fromsec, (long)faddr, tosec, tosec, tosec);
+ else
+ error("%s+0x%lx references non-executable section '%s'\n",
+ fromsec, (long)faddr, tosec);
}
}
-static int is_executable_section(struct elf_info* elf, unsigned int section_index)
+static void check_export_symbol(struct module *mod, struct elf_info *elf,
+ Elf_Addr faddr, const char *secname,
+ Elf_Sym *sym)
{
- if (section_index > elf->num_sections)
- fatal("section_index is outside elf->num_sections!\n");
+ static const char *prefix = "__export_symbol_";
+ const char *label_name, *name, *data;
+ Elf_Sym *label;
+ struct symbol *s;
+ bool is_gpl;
- return ((elf->sechdrs[section_index].sh_flags & SHF_EXECINSTR) == SHF_EXECINSTR);
-}
+ label = find_fromsym(elf, faddr, elf->export_symbol_secndx);
+ label_name = sym_name(elf, label);
-/*
- * We rely on a gross hack in section_rel[a]() calling find_extable_entry_size()
- * to know the sizeof(struct exception_table_entry) for the target architecture.
- */
-static unsigned int extable_entry_size = 0;
-static void find_extable_entry_size(const char* const sec, const Elf_Rela* r)
-{
- /*
- * If we're currently checking the second relocation within __ex_table,
- * that relocation offset tells us the offsetof(struct
- * exception_table_entry, fixup) which is equal to sizeof(struct
- * exception_table_entry) divided by two. We use that to our advantage
- * since there's no portable way to get that size as every architecture
- * seems to go with different sized types. Not pretty but better than
- * hard-coding the size for every architecture..
- */
- if (!extable_entry_size)
- extable_entry_size = r->r_offset * 2;
-}
+ if (!strstarts(label_name, prefix)) {
+ error("%s: .export_symbol section contains strange symbol '%s'\n",
+ mod->name, label_name);
+ return;
+ }
-static inline bool is_extable_fault_address(Elf_Rela *r)
-{
- /*
- * extable_entry_size is only discovered after we've handled the
- * _second_ relocation in __ex_table, so only abort when we're not
- * handling the first reloc and extable_entry_size is zero.
- */
- if (r->r_offset && extable_entry_size == 0)
- fatal("extable_entry size hasn't been discovered!\n");
-
- return ((r->r_offset == 0) ||
- (r->r_offset % extable_entry_size == 0));
-}
-
-#define is_second_extable_reloc(Start, Cur, Sec) \
- (((Cur) == (Start) + 1) && (strcmp("__ex_table", (Sec)) == 0))
-
-static void report_extable_warnings(const char* modname, struct elf_info* elf,
- const struct sectioncheck* const mismatch,
- Elf_Rela* r, Elf_Sym* sym,
- const char* fromsec, const char* tosec)
-{
- Elf_Sym* fromsym = find_elf_symbol2(elf, r->r_offset, fromsec);
- const char* fromsym_name = sym_name(elf, fromsym);
- Elf_Sym* tosym = find_elf_symbol(elf, r->r_addend, sym);
- const char* tosym_name = sym_name(elf, tosym);
- const char* from_pretty_name;
- const char* from_pretty_name_p;
- const char* to_pretty_name;
- const char* to_pretty_name_p;
-
- get_pretty_name(is_function(fromsym),
- &from_pretty_name, &from_pretty_name_p);
- get_pretty_name(is_function(tosym),
- &to_pretty_name, &to_pretty_name_p);
-
- warn("%s(%s+0x%lx): Section mismatch in reference from the %s %s%s to the %s %s:%s%s\n",
- modname, fromsec, (long)r->r_offset, from_pretty_name,
- fromsym_name, from_pretty_name_p,
- to_pretty_name, tosec, tosym_name, to_pretty_name_p);
-
- if (!match(tosec, mismatch->bad_tosec) &&
- is_executable_section(elf, get_secindex(elf, sym)))
- fprintf(stderr,
- "The relocation at %s+0x%lx references\n"
- "section \"%s\" which is not in the list of\n"
- "authorized sections. If you're adding a new section\n"
- "and/or if this reference is valid, add \"%s\" to the\n"
- "list of authorized sections to jump to on fault.\n"
- "This can be achieved by adding \"%s\" to \n"
- "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n",
- fromsec, (long)r->r_offset, tosec, tosec, tosec);
-}
-
-static void extable_mismatch_handler(const char* modname, struct elf_info *elf,
- const struct sectioncheck* const mismatch,
- Elf_Rela* r, Elf_Sym* sym,
- const char *fromsec)
-{
- const char* tosec = sec_name(elf, get_secindex(elf, sym));
+ if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
+ ELF_ST_BIND(sym->st_info) != STB_WEAK) {
+ error("%s: local symbol '%s' was exported\n", mod->name,
+ label_name + strlen(prefix));
+ return;
+ }
- sec_mismatch_count++;
+ name = sym_name(elf, sym);
+ if (strcmp(label_name + strlen(prefix), name)) {
+ error("%s: .export_symbol section references '%s', but it does not seem to be an export symbol\n",
+ mod->name, name);
+ return;
+ }
- report_extable_warnings(modname, elf, mismatch, r, sym, fromsec, tosec);
-
- if (match(tosec, mismatch->bad_tosec))
- fatal("The relocation at %s+0x%lx references\n"
- "section \"%s\" which is black-listed.\n"
- "Something is seriously wrong and should be fixed.\n"
- "You might get more information about where this is\n"
- "coming from by using scripts/check_extable.sh %s\n",
- fromsec, (long)r->r_offset, tosec, modname);
- else if (!is_executable_section(elf, get_secindex(elf, sym))) {
- if (is_extable_fault_address(r))
- fatal("The relocation at %s+0x%lx references\n"
- "section \"%s\" which is not executable, IOW\n"
- "it is not possible for the kernel to fault\n"
- "at that address. Something is seriously wrong\n"
- "and should be fixed.\n",
- fromsec, (long)r->r_offset, tosec);
- else
- fatal("The relocation at %s+0x%lx references\n"
- "section \"%s\" which is not executable, IOW\n"
- "the kernel will fault if it ever tries to\n"
- "jump to it. Something is seriously wrong\n"
- "and should be fixed.\n",
- fromsec, (long)r->r_offset, tosec);
+ data = sym_get_data(elf, label); /* license */
+ if (!strcmp(data, "GPL")) {
+ is_gpl = true;
+ } else if (!strcmp(data, "")) {
+ is_gpl = false;
+ } else {
+ error("%s: unknown license '%s' was specified for '%s'\n",
+ mod->name, data, name);
+ return;
}
+
+ data += strlen(data) + 1; /* namespace */
+ s = sym_add_exported(name, mod, is_gpl, data);
+
+ /*
+ * We need to be aware whether we are exporting a function or
+ * a data on some architectures.
+ */
+ s->is_func = (ELF_ST_TYPE(sym->st_info) == STT_FUNC);
+
+ if (match(secname, PATTERNS(INIT_SECTIONS)))
+ warn("%s: %s: EXPORT_SYMBOL used for init symbol. Remove __init or EXPORT_SYMBOL.\n",
+ mod->name, name);
+ else if (match(secname, PATTERNS(EXIT_SECTIONS)))
+ warn("%s: %s: EXPORT_SYMBOL used for exit symbol. Remove __exit or EXPORT_SYMBOL.\n",
+ mod->name, name);
}
-static void check_section_mismatch(const char *modname, struct elf_info *elf,
- Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
+static void check_section_mismatch(struct module *mod, struct elf_info *elf,
+ Elf_Sym *sym,
+ unsigned int fsecndx, const char *fromsec,
+ Elf_Addr faddr, Elf_Addr taddr)
{
const char *tosec = sec_name(elf, get_secindex(elf, sym));
- const struct sectioncheck *mismatch = section_mismatch(fromsec, tosec);
+ const struct sectioncheck *mismatch;
- if (mismatch) {
- if (mismatch->handler)
- mismatch->handler(modname, elf, mismatch,
- r, sym, fromsec);
- else
- default_mismatch_handler(modname, elf, mismatch,
- r, sym, fromsec);
+ if (elf->export_symbol_secndx == fsecndx) {
+ check_export_symbol(mod, elf, faddr, tosec, sym);
+ return;
}
-}
-static unsigned int *reloc_location(struct elf_info *elf,
- Elf_Shdr *sechdr, Elf_Rela *r)
-{
- return sym_get_data_by_offset(elf, sechdr->sh_info, r->r_offset);
+ mismatch = section_mismatch(fromsec, tosec);
+ if (!mismatch)
+ return;
+
+ default_mismatch_handler(mod->name, elf, mismatch, sym,
+ fsecndx, fromsec, faddr,
+ tosec, taddr);
}
-static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
+static int addend_386_rel(uint32_t *location, Elf_Rela *r)
{
unsigned int r_typ = ELF_R_TYPE(r->r_info);
- unsigned int *location = reloc_location(elf, sechdr, r);
switch (r_typ) {
case R_386_32:
case R_386_PC32:
r->r_addend = TO_NATIVE(*location) + 4;
break;
+ default:
+ r->r_addend = (Elf_Addr)(-1);
}
return 0;
}
#ifndef R_ARM_THM_JUMP24
#define R_ARM_THM_JUMP24 30
#endif
+
+#ifndef R_ARM_MOVW_ABS_NC
+#define R_ARM_MOVW_ABS_NC 43
+#endif
+
+#ifndef R_ARM_MOVT_ABS
+#define R_ARM_MOVT_ABS 44
+#endif
+
+#ifndef R_ARM_THM_MOVW_ABS_NC
+#define R_ARM_THM_MOVW_ABS_NC 47
+#endif
+
+#ifndef R_ARM_THM_MOVT_ABS
+#define R_ARM_THM_MOVT_ABS 48
+#endif
+
#ifndef R_ARM_THM_JUMP19
#define R_ARM_THM_JUMP19 51
#endif
-static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
+static int32_t sign_extend32(int32_t value, int index)
+{
+ uint8_t shift = 31 - index;
+
+ return (int32_t)(value << shift) >> shift;
+}
+
+static int addend_arm_rel(void *loc, Elf_Sym *sym, Elf_Rela *r)
{
unsigned int r_typ = ELF_R_TYPE(r->r_info);
+ uint32_t inst, upper, lower, sign, j1, j2;
+ int32_t offset;
switch (r_typ) {
case R_ARM_ABS32:
- /* From ARM ABI: (S + A) | T */
- r->r_addend = (int)(long)
- (elf->symtab_start + ELF_R_SYM(r->r_info));
+ case R_ARM_REL32:
+ inst = TO_NATIVE(*(uint32_t *)loc);
+ r->r_addend = inst + sym->st_value;
+ break;
+ case R_ARM_MOVW_ABS_NC:
+ case R_ARM_MOVT_ABS:
+ inst = TO_NATIVE(*(uint32_t *)loc);
+ offset = sign_extend32(((inst & 0xf0000) >> 4) | (inst & 0xfff),
+ 15);
+ r->r_addend = offset + sym->st_value;
break;
case R_ARM_PC24:
case R_ARM_CALL:
case R_ARM_JUMP24:
+ inst = TO_NATIVE(*(uint32_t *)loc);
+ offset = sign_extend32((inst & 0x00ffffff) << 2, 25);
+ r->r_addend = offset + sym->st_value + 8;
+ break;
+ case R_ARM_THM_MOVW_ABS_NC:
+ case R_ARM_THM_MOVT_ABS:
+ upper = TO_NATIVE(*(uint16_t *)loc);
+ lower = TO_NATIVE(*((uint16_t *)loc + 1));
+ offset = sign_extend32(((upper & 0x000f) << 12) |
+ ((upper & 0x0400) << 1) |
+ ((lower & 0x7000) >> 4) |
+ (lower & 0x00ff),
+ 15);
+ r->r_addend = offset + sym->st_value;
+ break;
+ case R_ARM_THM_JUMP19:
+ /*
+ * Encoding T3:
+ * S = upper[10]
+ * imm6 = upper[5:0]
+ * J1 = lower[13]
+ * J2 = lower[11]
+ * imm11 = lower[10:0]
+ * imm32 = SignExtend(S:J2:J1:imm6:imm11:'0')
+ */
+ upper = TO_NATIVE(*(uint16_t *)loc);
+ lower = TO_NATIVE(*((uint16_t *)loc + 1));
+
+ sign = (upper >> 10) & 1;
+ j1 = (lower >> 13) & 1;
+ j2 = (lower >> 11) & 1;
+ offset = sign_extend32((sign << 20) | (j2 << 19) | (j1 << 18) |
+ ((upper & 0x03f) << 12) |
+ ((lower & 0x07ff) << 1),
+ 20);
+ r->r_addend = offset + sym->st_value + 4;
+ break;
case R_ARM_THM_CALL:
case R_ARM_THM_JUMP24:
- case R_ARM_THM_JUMP19:
- /* From ARM ABI: ((S + A) | T) - P */
- r->r_addend = (int)(long)(elf->hdr +
- sechdr->sh_offset +
- (r->r_offset - sechdr->sh_addr));
+ /*
+ * Encoding T4:
+ * S = upper[10]
+ * imm10 = upper[9:0]
+ * J1 = lower[13]
+ * J2 = lower[11]
+ * imm11 = lower[10:0]
+ * I1 = NOT(J1 XOR S)
+ * I2 = NOT(J2 XOR S)
+ * imm32 = SignExtend(S:I1:I2:imm10:imm11:'0')
+ */
+ upper = TO_NATIVE(*(uint16_t *)loc);
+ lower = TO_NATIVE(*((uint16_t *)loc + 1));
+
+ sign = (upper >> 10) & 1;
+ j1 = (lower >> 13) & 1;
+ j2 = (lower >> 11) & 1;
+ offset = sign_extend32((sign << 24) |
+ ((~(j1 ^ sign) & 1) << 23) |
+ ((~(j2 ^ sign) & 1) << 22) |
+ ((upper & 0x03ff) << 12) |
+ ((lower & 0x07ff) << 1),
+ 24);
+ r->r_addend = offset + sym->st_value + 4;
break;
default:
- return 1;
+ r->r_addend = (Elf_Addr)(-1);
}
return 0;
}
-static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
+static int addend_mips_rel(uint32_t *location, Elf_Rela *r)
{
unsigned int r_typ = ELF_R_TYPE(r->r_info);
- unsigned int *location = reloc_location(elf, sechdr, r);
- unsigned int inst;
+ uint32_t inst;
- if (r_typ == R_MIPS_HI16)
- return 1; /* skip this */
inst = TO_NATIVE(*location);
switch (r_typ) {
case R_MIPS_LO16:
case R_MIPS_32:
r->r_addend = inst;
break;
+ default:
+ r->r_addend = (Elf_Addr)(-1);
}
return 0;
}
#define R_LARCH_SUB32 55
#endif
-static void section_rela(const char *modname, struct elf_info *elf,
+static void section_rela(struct module *mod, struct elf_info *elf,
Elf_Shdr *sechdr)
{
- Elf_Sym *sym;
Elf_Rela *rela;
Elf_Rela r;
unsigned int r_sym;
- const char *fromsec;
-
+ unsigned int fsecndx = sechdr->sh_info;
+ const char *fromsec = sec_name(elf, fsecndx);
Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
Elf_Rela *stop = (void *)start + sechdr->sh_size;
- fromsec = sec_name(elf, sechdr->sh_info);
/* if from section (name) is know good then skip it */
if (match(fromsec, section_white_list))
return;
continue;
break;
}
- sym = elf->symtab_start + r_sym;
- /* Skip special sections */
- if (is_shndx_special(sym->st_shndx))
- continue;
- if (is_second_extable_reloc(start, rela, fromsec))
- find_extable_entry_size(fromsec, &r);
- check_section_mismatch(modname, elf, &r, sym, fromsec);
+
+ check_section_mismatch(mod, elf, elf->symtab_start + r_sym,
+ fsecndx, fromsec, r.r_offset, r.r_addend);
}
}
-static void section_rel(const char *modname, struct elf_info *elf,
+static void section_rel(struct module *mod, struct elf_info *elf,
Elf_Shdr *sechdr)
{
- Elf_Sym *sym;
Elf_Rel *rel;
Elf_Rela r;
unsigned int r_sym;
- const char *fromsec;
-
+ unsigned int fsecndx = sechdr->sh_info;
+ const char *fromsec = sec_name(elf, fsecndx);
Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
Elf_Rel *stop = (void *)start + sechdr->sh_size;
- fromsec = sec_name(elf, sechdr->sh_info);
/* if from section (name) is know good then skip it */
if (match(fromsec, section_white_list))
return;
for (rel = start; rel < stop; rel++) {
+ Elf_Sym *tsym;
+ void *loc;
+
r.r_offset = TO_NATIVE(rel->r_offset);
#if KERNEL_ELFCLASS == ELFCLASS64
if (elf->hdr->e_machine == EM_MIPS) {
r_sym = ELF_R_SYM(r.r_info);
#endif
r.r_addend = 0;
+
+ loc = sym_get_data_by_offset(elf, fsecndx, r.r_offset);
+ tsym = elf->symtab_start + r_sym;
+
switch (elf->hdr->e_machine) {
case EM_386:
- if (addend_386_rel(elf, sechdr, &r))
- continue;
+ addend_386_rel(loc, &r);
break;
case EM_ARM:
- if (addend_arm_rel(elf, sechdr, &r))
- continue;
+ addend_arm_rel(loc, tsym, &r);
break;
case EM_MIPS:
- if (addend_mips_rel(elf, sechdr, &r))
- continue;
+ addend_mips_rel(loc, &r);
break;
+ default:
+ fatal("Please add code to calculate addend for this architecture\n");
}
- sym = elf->symtab_start + r_sym;
- /* Skip special sections */
- if (is_shndx_special(sym->st_shndx))
- continue;
- if (is_second_extable_reloc(start, rel, fromsec))
- find_extable_entry_size(fromsec, &r);
- check_section_mismatch(modname, elf, &r, sym, fromsec);
+
+ check_section_mismatch(mod, elf, tsym,
+ fsecndx, fromsec, r.r_offset, r.r_addend);
}
}
* to find all references to a section that reference a section that will
* be discarded and warns about it.
**/
-static void check_sec_ref(const char *modname, struct elf_info *elf)
+static void check_sec_ref(struct module *mod, struct elf_info *elf)
{
int i;
Elf_Shdr *sechdrs = elf->sechdrs;
/* Walk through all sections */
for (i = 0; i < elf->num_sections; i++) {
- check_section(modname, elf, &elf->sechdrs[i]);
+ check_section(mod->name, elf, &elf->sechdrs[i]);
/* We want to process only relocation sections and not .init */
if (sechdrs[i].sh_type == SHT_RELA)
- section_rela(modname, elf, &elf->sechdrs[i]);
+ section_rela(mod, elf, &elf->sechdrs[i]);
else if (sechdrs[i].sh_type == SHT_REL)
- section_rel(modname, elf, &elf->sechdrs[i]);
+ section_rel(mod, elf, &elf->sechdrs[i]);
}
}
}
}
+ if (extra_warn && !get_modinfo(&info, "description"))
+ warn("missing MODULE_DESCRIPTION() in %s\n", modname);
for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
symname = remove_dot(info.strtab + sym->st_name);
handle_moddevtable(mod, &info, sym, symname);
}
- for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
- symname = remove_dot(info.strtab + sym->st_name);
-
- /* Apply symbol namespaces from __kstrtabns_<symbol> entries. */
- if (strstarts(symname, "__kstrtabns_"))
- sym_update_namespace(symname + strlen("__kstrtabns_"),
- sym_get_data(&info, sym));
- }
-
- check_sec_ref(modname, &info);
+ check_sec_ref(mod, &info);
if (!mod->is_vmlinux) {
version = get_modinfo(&info, "version");
continue;
}
+ exp->used = true;
s->module = exp->module;
s->crc_valid = exp->crc_valid;
s->crc = exp->crc;
else
basename = mod->name;
- if (exp->namespace &&
- !contains_namespace(&mod->imported_namespaces, exp->namespace)) {
+ if (!contains_namespace(&mod->imported_namespaces, exp->namespace)) {
modpost_log(allow_missing_ns_imports ? LOG_WARN : LOG_ERROR,
"module %s uses symbol %s from namespace %s, but does not import it.\n",
basename, exp->name, exp->namespace);
}
}
+static void handle_white_list_exports(const char *white_list)
+{
+ char *buf, *p, *name;
+
+ buf = read_text_file(white_list);
+ p = buf;
+
+ while ((name = strsep(&p, "\n"))) {
+ struct symbol *sym = find_symbol(name);
+
+ if (sym)
+ sym->used = true;
+ }
+
+ free(buf);
+}
+
static void check_modname_len(struct module *mod)
{
const char *mod_name;
{
struct symbol *sym;
+ /* generate struct for exported symbols */
+ buf_printf(buf, "\n");
+ list_for_each_entry(sym, &mod->exported_symbols, list) {
+ if (trim_unused_exports && !sym->used)
+ continue;
+
+ buf_printf(buf, "KSYMTAB_%s(%s, \"%s\", \"%s\");\n",
+ sym->is_func ? "FUNC" : "DATA", sym->name,
+ sym->is_gpl_only ? "_gpl" : "", sym->namespace);
+ }
+
if (!modversions)
return;
/* record CRCs for exported symbols */
buf_printf(buf, "\n");
list_for_each_entry(sym, &mod->exported_symbols, list) {
+ if (trim_unused_exports && !sym->used)
+ continue;
+
if (!sym->crc_valid)
warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n"
"Is \"%s\" prototyped in <asm/asm-prototypes.h>?\n",
char fname[PATH_MAX];
int ret;
- check_modname_len(mod);
- check_exports(mod);
-
add_header(&buf, mod);
add_exported_symbols(&buf, mod);
add_versions(&buf, mod);
mod = new_module(modname, strlen(modname));
mod->from_dump = true;
}
- s = sym_add_exported(symname, mod, gpl_only);
+ s = sym_add_exported(symname, mod, gpl_only, namespace);
sym_set_crc(s, crc);
- sym_update_namespace(symname, namespace);
}
free(buf);
return;
if (mod->from_dump)
continue;
list_for_each_entry(sym, &mod->exported_symbols, list) {
+ if (trim_unused_exports && !sym->used)
+ continue;
+
buf_printf(&buf, "0x%08x\t%s\t%s\tEXPORT_SYMBOL%s\t%s\n",
sym->crc, sym->name, mod->name,
sym->is_gpl_only ? "_GPL" : "",
- sym->namespace ?: "");
+ sym->namespace);
}
}
write_buf(&buf, fname);
{
struct module *mod;
char *missing_namespace_deps = NULL;
+ char *unused_exports_white_list = NULL;
char *dump_write = NULL, *files_source = NULL;
int opt;
LIST_HEAD(dump_lists);
struct dump_list *dl, *dl2;
- while ((opt = getopt(argc, argv, "ei:mnT:o:awENd:")) != -1) {
+ while ((opt = getopt(argc, argv, "ei:mnT:to:au:WwENd:")) != -1) {
switch (opt) {
case 'e':
external_module = true;
case 'T':
files_source = optarg;
break;
+ case 't':
+ trim_unused_exports = true;
+ break;
+ case 'u':
+ unused_exports_white_list = optarg;
+ break;
+ case 'W':
+ extra_warn = true;
+ break;
case 'w':
warn_unresolved = true;
break;
read_symbols_from_files(files_source);
list_for_each_entry(mod, &modules, list) {
+ if (mod->from_dump || mod->is_vmlinux)
+ continue;
+
+ check_modname_len(mod);
+ check_exports(mod);
+ }
+
+ if (unused_exports_white_list)
+ handle_white_list_exports(unused_exports_white_list);
+
+ list_for_each_entry(mod, &modules, list) {
if (mod->from_dump)
continue;
projects / platform / kernel / linux-rpi.git / blobdiff