diff options
Diffstat (limited to 'kernel/kallsyms.c')
| -rw-r--r-- | kernel/kallsyms.c | 99 |
1 files changed, 20 insertions, 79 deletions
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 18edd57b5fe8..4198f30aac3c 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -148,51 +148,8 @@ static unsigned int get_symbol_offset(unsigned long pos) unsigned long kallsyms_sym_address(int idx) { - if (!IS_ENABLED(CONFIG_KALLSYMS_BASE_RELATIVE)) - return kallsyms_addresses[idx]; - - /* values are unsigned offsets if --absolute-percpu is not in effect */ - if (!IS_ENABLED(CONFIG_KALLSYMS_ABSOLUTE_PERCPU)) - return kallsyms_relative_base + (u32)kallsyms_offsets[idx]; - - /* ...otherwise, positive offsets are absolute values */ - if (kallsyms_offsets[idx] >= 0) - return kallsyms_offsets[idx]; - - /* ...and negative offsets are relative to kallsyms_relative_base - 1 */ - return kallsyms_relative_base - 1 - kallsyms_offsets[idx]; -} - -static void cleanup_symbol_name(char *s) -{ - char *res; - - if (!IS_ENABLED(CONFIG_LTO_CLANG)) - return; - - /* - * 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 only in LLVM LTO observed: - * - foo.llvm.[0-9a-f]+ - */ - res = strstr(s, ".llvm."); - if (res) - *res = '\0'; - - return; -} - -static int compare_symbol_name(const char *name, char *namebuf) -{ - /* The kallsyms_seqs_of_names is sorted based on names after - * cleanup_symbol_name() (see scripts/kallsyms.c) if clang lto is enabled. - * To ensure correct bisection in kallsyms_lookup_names(), do - * cleanup_symbol_name(namebuf) before comparing name and namebuf. - */ - cleanup_symbol_name(namebuf); - return strcmp(name, namebuf); + /* values are unsigned offsets */ + return kallsyms_relative_base + (u32)kallsyms_offsets[idx]; } static unsigned int get_symbol_seq(int index) @@ -222,7 +179,7 @@ static int kallsyms_lookup_names(const char *name, seq = get_symbol_seq(mid); off = get_symbol_offset(seq); kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf)); - ret = compare_symbol_name(name, namebuf); + ret = strcmp(name, namebuf); if (ret > 0) low = mid + 1; else if (ret < 0) @@ -239,7 +196,7 @@ static int kallsyms_lookup_names(const char *name, seq = get_symbol_seq(low - 1); off = get_symbol_offset(seq); kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf)); - if (compare_symbol_name(name, namebuf)) + if (strcmp(name, namebuf)) break; low--; } @@ -251,7 +208,7 @@ static int kallsyms_lookup_names(const char *name, seq = get_symbol_seq(high + 1); off = get_symbol_offset(seq); kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf)); - if (compare_symbol_name(name, namebuf)) + if (strcmp(name, namebuf)) break; high++; } @@ -325,13 +282,7 @@ static unsigned long get_symbol_pos(unsigned long addr, unsigned long symbol_start = 0, symbol_end = 0; unsigned long i, low, high, mid; - /* This kernel should never had been booted. */ - if (!IS_ENABLED(CONFIG_KALLSYMS_BASE_RELATIVE)) - BUG_ON(!kallsyms_addresses); - else - BUG_ON(!kallsyms_offsets); - - /* Do a binary search on the sorted kallsyms_addresses array. */ + /* Do a binary search on the sorted kallsyms_offsets array. */ low = 0; high = kallsyms_num_syms; @@ -394,12 +345,12 @@ int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize, !!__bpf_address_lookup(addr, symbolsize, offset, namebuf); } -static const char *kallsyms_lookup_buildid(unsigned long addr, +static int kallsyms_lookup_buildid(unsigned long addr, unsigned long *symbolsize, unsigned long *offset, char **modname, const unsigned char **modbuildid, char *namebuf) { - const char *ret; + int ret; namebuf[KSYM_NAME_LEN - 1] = 0; namebuf[0] = 0; @@ -416,8 +367,7 @@ static const char *kallsyms_lookup_buildid(unsigned long addr, if (modbuildid) *modbuildid = NULL; - ret = namebuf; - goto found; + return strlen(namebuf); } /* See if it's in a module or a BPF JITed image. */ @@ -431,8 +381,6 @@ static const char *kallsyms_lookup_buildid(unsigned long addr, ret = ftrace_mod_address_lookup(addr, symbolsize, offset, modname, namebuf); -found: - cleanup_symbol_name(namebuf); return ret; } @@ -448,14 +396,17 @@ const char *kallsyms_lookup(unsigned long addr, unsigned long *offset, char **modname, char *namebuf) { - return kallsyms_lookup_buildid(addr, symbolsize, offset, modname, - NULL, namebuf); + int ret = kallsyms_lookup_buildid(addr, symbolsize, offset, modname, + NULL, namebuf); + + if (!ret) + return NULL; + + return namebuf; } int lookup_symbol_name(unsigned long addr, char *symname) { - int res; - symname[0] = '\0'; symname[KSYM_NAME_LEN - 1] = '\0'; @@ -466,16 +417,10 @@ int lookup_symbol_name(unsigned long addr, char *symname) /* Grab name */ kallsyms_expand_symbol(get_symbol_offset(pos), symname, KSYM_NAME_LEN); - goto found; + return 0; } /* See if it's in a module. */ - res = lookup_module_symbol_name(addr, symname); - if (res) - return res; - -found: - cleanup_symbol_name(symname); - return 0; + return lookup_module_symbol_name(addr, symname); } /* Look up a kernel symbol and return it in a text buffer. */ @@ -484,19 +429,15 @@ static int __sprint_symbol(char *buffer, unsigned long address, { char *modname; const unsigned char *buildid; - const char *name; unsigned long offset, size; int len; address += symbol_offset; - name = kallsyms_lookup_buildid(address, &size, &offset, &modname, &buildid, + len = kallsyms_lookup_buildid(address, &size, &offset, &modname, &buildid, buffer); - if (!name) + if (!len) return sprintf(buffer, "0x%lx", address - symbol_offset); - if (name != buffer) - strcpy(buffer, name); - len = strlen(buffer); offset -= symbol_offset; if (add_offset) |