summaryrefslogtreecommitdiff
path: root/absl/debugging/symbolize_elf.inc
diff options
context:
space:
mode:
Diffstat (limited to 'absl/debugging/symbolize_elf.inc')
-rw-r--r--absl/debugging/symbolize_elf.inc13
1 files changed, 10 insertions, 3 deletions
diff --git a/absl/debugging/symbolize_elf.inc b/absl/debugging/symbolize_elf.inc
index e7305213..14f0c972 100644
--- a/absl/debugging/symbolize_elf.inc
+++ b/absl/debugging/symbolize_elf.inc
@@ -624,6 +624,13 @@ static bool InSection(const void *address, const ElfW(Shdr) * section) {
return start <= address && address < (start + size);
}
+static const char *ComputeOffset(const char *base, ptrdiff_t offset) {
+ // Note: cast to uintptr_t to avoid undefined behavior when base evaluates to
+ // zero and offset is non-zero.
+ return reinterpret_cast<const char *>(
+ reinterpret_cast<uintptr_t>(base) + offset);
+}
+
// Read a symbol table and look for the symbol containing the
// pc. Iterate over symbols in a symbol table and look for the symbol
// containing "pc". If the symbol is found, and its name fits in
@@ -676,7 +683,8 @@ static ABSL_ATTRIBUTE_NOINLINE FindSymbolResult FindSymbol(
// We keep the original address for opd redirection below.
const char *const original_start_address =
reinterpret_cast<const char *>(symbol.st_value);
- const char *start_address = original_start_address + relocation;
+ const char *start_address =
+ ComputeOffset(original_start_address, relocation);
if (deref_function_descriptor_pointer &&
InSection(original_start_address, opd)) {
@@ -688,8 +696,7 @@ static ABSL_ATTRIBUTE_NOINLINE FindSymbolResult FindSymbol(
// If pc is inside the .opd section, it points to a function descriptor.
const size_t size = pc_in_opd ? kFunctionDescriptorSize : symbol.st_size;
- const void *const end_address =
- reinterpret_cast<const char *>(start_address) + size;
+ const void *const end_address = ComputeOffset(start_address, size);
if (symbol.st_value != 0 && // Skip null value symbols.
symbol.st_shndx != 0 && // Skip undefined symbols.
#ifdef STT_TLS