@@ -1021,6 +1021,18 @@ static Elf_Sym *find_tosym(struct elf_info *elf, Elf_Addr addr, Elf_Sym *sym)
true, 20);
}
+static Elf_Sym *find_tosym_with_name(struct elf_info *elf, Elf_Addr addr,
+ Elf_Sym *sym, const char *name)
+{
+ /* If the supplied symbol has the expected name, return it. */
+ if (!strcmp(sym_name(elf, sym), name))
+ return sym;
+
+ /* Look up a symbol with the given name. */
+ return symsearch_find_with_name(elf, addr, get_secindex(elf, sym),
+ true, 20, name);
+}
+
static bool is_executable_section(struct elf_info *elf, unsigned int secndx)
{
if (secndx >= elf->num_sections)
@@ -1079,7 +1091,7 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf,
static void check_export_symbol(struct module *mod, struct elf_info *elf,
Elf_Addr faddr, const char *secname,
- Elf_Sym *sym)
+ Elf_Sym *sym, Elf_Addr taddr)
{
static const char *prefix = "__export_symbol_";
const char *label_name, *name, *data;
@@ -1096,6 +1108,14 @@ static void check_export_symbol(struct module *mod, struct elf_info *elf,
return;
}
+ name = label_name + strlen(prefix);
+ sym = find_tosym_with_name(elf, taddr, sym, name);
+ if (!sym) {
+ error("%s: could not find the the export symbol '%s'\n",
+ mod->name, name);
+ return;
+ }
+
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,
@@ -1103,13 +1123,6 @@ static void check_export_symbol(struct module *mod, struct elf_info *elf,
return;
}
- 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;
- }
-
data = sym_get_data(elf, label); /* license */
if (!strcmp(data, "GPL")) {
is_gpl = true;
@@ -1156,7 +1169,7 @@ static void check_section_mismatch(struct module *mod, struct elf_info *elf,
const struct sectioncheck *mismatch;
if (module_enabled && elf->export_symbol_secndx == fsecndx) {
- check_export_symbol(mod, elf, faddr, tosec, sym);
+ check_export_symbol(mod, elf, faddr, tosec, sym, taddr);
return;
}
Greg Ungerer reported modpost produced false-positive "local symbol '...' was exported" errors when m68k-uclinux-gcc is used. I had assumed ELF_R_SYM(Elf_Rela::r_info) pointed to the exported symbol itself if it is in the global scope. This assumption worked for many toolchains, but as it turned out, it was not true for m68k-uclinux-gcc, at least. If the 'sym' argument passed to check_export_symbol() is not the exported symbol, look up the correct one in the symbol table. It incurs a search cost, but since we know its section index and address, we can exploit the binary search. Reported-by: Greg Ungerer <gerg@kernel.org> Closes: https://lore.kernel.org/all/1fac9d12-2ec2-4ccb-bb81-34f3fc34789e@westnet.com.au/ Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> --- scripts/mod/modpost.c | 31 ++++++++++++++++++++++--------- 1 file changed, 22 insertions(+), 9 deletions(-)