diff options
Diffstat (limited to 'kernel/kallsyms.c')
| -rw-r--r-- | kernel/kallsyms.c | 46 |
1 files changed, 33 insertions, 13 deletions
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 0ba87982d017..3011bc33a5ba 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -164,26 +164,46 @@ static unsigned long kallsyms_sym_address(int idx) return kallsyms_relative_base - 1 - kallsyms_offsets[idx]; } -#if defined(CONFIG_CFI_CLANG) && defined(CONFIG_LTO_CLANG_THIN) -/* - * LLVM appends a hash to static function names when ThinLTO and CFI are - * both enabled, i.e. foo() becomes foo$707af9a22804d33c81801f27dcfe489b. - * This causes confusion and potentially breaks user space tools, so we - * strip the suffix from expanded symbol names. - */ -static inline bool cleanup_symbol_name(char *s) +static bool cleanup_symbol_name(char *s) { char *res; + if (!IS_ENABLED(CONFIG_LTO_CLANG)) + return false; + + /* + * LLVM appends various suffixes for local functions and variables that + * must be promoted to global scope as part of LTO. This can break + * hooking of static functions with kprobes. '.' is not a valid + * character in an identifier in C. Suffixes observed: + * - foo.llvm.[0-9a-f]+ + * - foo.[0-9a-f]+ + * - foo.[0-9a-f]+.cfi_jt + */ + res = strchr(s, '.'); + if (res) { + *res = '\0'; + return true; + } + + if (!IS_ENABLED(CONFIG_CFI_CLANG) || + !IS_ENABLED(CONFIG_LTO_CLANG_THIN) || + CONFIG_CLANG_VERSION >= 130000) + return false; + + /* + * Prior to LLVM 13, the following suffixes were observed when thinLTO + * and CFI are both enabled: + * - foo$[0-9]+ + */ res = strrchr(s, '$'); - if (res) + if (res) { *res = '\0'; + return true; + } - return res != NULL; + return false; } -#else -static inline bool cleanup_symbol_name(char *s) { return false; } -#endif /* Lookup the address for this symbol. Returns 0 if not found. */ unsigned long kallsyms_lookup_name(const char *name) |