path: root/src
diff options
authorSzabolcs Nagy <>2015-11-26 19:59:46 +0100
committerRich Felker <>2015-11-28 13:34:17 -0500
commit12978acb3066db738c8c15121e81adbb63739876 (patch)
treead1b75f4b307190f31416438b8c6de8494c8f62e /src
parent8eead3ef18ea71a64ef3cbff8c09bac3b82f1242 (diff)
ldso: fix the dtv update logic in __tls_get_new
if two or more threads accessed tls in a dso that was loaded after the threads were created, then __tls_get_new could do out-of-bound memory access (leading to segfault). accidentally byte count was used instead of element count when the new dtv pointer was computed. (dso->new_dtv is (void**).) it is rare that the same dso provides dtv for several threads, the crash was not observed in practice, but possible to trigger.
Diffstat (limited to 'src')
1 files changed, 1 insertions, 1 deletions
diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index 4648e9ac..93e7d67e 100644
--- a/src/ldso/dynlink.c
+++ b/src/ldso/dynlink.c
@@ -1280,7 +1280,7 @@ void *__tls_get_new(size_t *v)
/* Get new DTV space from new DSO if needed */
if (v[0] > (size_t)self->dtv[0]) {
void **newdtv = p->new_dtv +
- (v[0]+1)*sizeof(void *)*a_fetch_add(&p->new_dtv_idx,1);
+ (v[0]+1)*a_fetch_add(&p->new_dtv_idx,1);
memcpy(newdtv, self->dtv,
((size_t)self->dtv[0]+1) * sizeof(void *));
newdtv[0] = (void *)v[0];