diff options
Diffstat (limited to 'elf/dl-tls.c')
| -rw-r--r-- | elf/dl-tls.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/elf/dl-tls.c b/elf/dl-tls.c index 7b3dd9ab60..670dbc42fc 100644 --- a/elf/dl-tls.c +++ b/elf/dl-tls.c @@ -819,7 +819,14 @@ _dl_update_slotinfo (unsigned long int req_modid, size_t new_gen) dtv entry free it. Note: this is not AS-safe. */ /* XXX Ideally we will at some point create a memory pool. */ - free (dtv[modid].pointer.to_free); + /* Avoid calling free on a null pointer. Some mallocs + incorrectly use dynamic TLS, and depending on how the + free function was compiled, it could call + __tls_get_addr before the null pointer check in the + free implementation. Checking here papers over at + least some dynamic TLS usage by interposed mallocs. */ + if (dtv[modid].pointer.to_free != NULL) + free (dtv[modid].pointer.to_free); dtv[modid].pointer.val = TLS_DTV_UNALLOCATED; dtv[modid].pointer.to_free = NULL; |