unwind: ignore memory mappings that have no PROT_EXEC bit set
* unwind.c (build_mmap_cache): For each memory mapping being scanned,
save its PROT_EXEC bit and skip the mapping if it is not set.
diff --git a/unwind.c b/unwind.c
index 2e80926..5b06008 100644
--- a/unwind.c
+++ b/unwind.c
@@ -159,11 +159,16 @@
while (fgets(buffer, sizeof(buffer), fp) != NULL) {
struct mmap_cache_t *entry;
unsigned long start_addr, end_addr, mmap_offset;
+ char exec_bit;
char binary_path[PATH_MAX];
if (sscanf(buffer, "%lx-%lx %*c%*c%c%*c %lx %*x:%*x %*d %[^\n]",
- &start_addr, &end_addr,
- &mmap_offset, binary_path) != 4)
+ &start_addr, &end_addr, &exec_bit,
+ &mmap_offset, binary_path) != 5)
+ continue;
+
+ /* ignore mappings that have no PROT_EXEC bit set */
+ if (exec_bit != 'x')
continue;
if (end_addr < start_addr) {
@@ -177,7 +182,6 @@
*/
if (tcp->mmap_cache_size > 0) {
entry = &cache_head[tcp->mmap_cache_size - 1];
-
if (entry->start_addr == start_addr &&
entry->end_addr == end_addr) {
/* duplicate entry, e.g. [vsyscall] */