diff options
| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2020-02-18 04:41:54 +0100 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2020-02-21 10:20:34 +0100 |
| commit | 7acfe5315312fc56c2a94c9216448087b38ae909 (patch) | |
| tree | e3187f3209664e907dabf0fa7a0151d1a82e487f /tools/objtool/elf.c | |
| parent | objtool: Fix clang switch table edge case (diff) | |
| download | linux-7acfe5315312fc56c2a94c9216448087b38ae909.tar.xz linux-7acfe5315312fc56c2a94c9216448087b38ae909.zip | |
objtool: Improve call destination function detection
A recent clang change, combined with a binutils bug, can trigger a
situation where a ".Lprintk$local" STT_NOTYPE symbol gets created at the
same offset as the "printk" STT_FUNC symbol. This confuses objtool:
kernel/printk/printk.o: warning: objtool: ignore_loglevel_setup()+0x10: can't find call dest symbol at .text+0xc67
Improve the call destination detection by looking specifically for an
STT_FUNC symbol.
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/872
Link: https://sourceware.org/bugzilla/show_bug.cgi?id=25551
Link: https://lkml.kernel.org/r/0a7ee320bc0ea4469bd3dc450a7b4725669e0ea9.1581997059.git.jpoimboe@redhat.com
Diffstat (limited to 'tools/objtool/elf.c')
| -rw-r--r-- | tools/objtool/elf.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c index edba4745f25a..cc4601c879ce 100644 --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -62,8 +62,18 @@ struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset) struct symbol *sym; list_for_each_entry(sym, &sec->symbol_list, list) - if (sym->type != STT_SECTION && - sym->offset == offset) + if (sym->type != STT_SECTION && sym->offset == offset) + return sym; + + return NULL; +} + +struct symbol *find_func_by_offset(struct section *sec, unsigned long offset) +{ + struct symbol *sym; + + list_for_each_entry(sym, &sec->symbol_list, list) + if (sym->type == STT_FUNC && sym->offset == offset) return sym; return NULL; |