path: root/src/env
diff options
authorRich Felker <>2015-04-23 18:51:02 -0400
committerRich Felker <>2015-04-23 18:51:02 -0400
commitabead1be6d4a303037ee65a4009c59e5b5fe0a82 (patch)
tree1bce96044564e5b7f7ecbaa6730c034235d4e79a /src/env
parent23129ab8d5f86927aad4f67c1820362acce09c45 (diff)
fix misalignment of dtv in static-linked programs with odd-sized TLS
both static and dynamic linked versions of the __copy_tls function have a hidden assumption that the alignment of the beginning or end of the memory passed is suitable for storing an array of pointers for the dtv. pthread_create satisfies this requirement except when libc.tls_size is misaligned, which cannot happen with dynamic linking due to way update_tls_size computes the total size, but could happen with static linking and odd-sized TLS.
Diffstat (limited to 'src/env')
1 files changed, 2 insertions, 1 deletions
diff --git a/src/env/__init_tls.c b/src/env/__init_tls.c
index b4df2ba5..73551e6c 100644
--- a/src/env/__init_tls.c
+++ b/src/env/__init_tls.c
@@ -95,7 +95,8 @@ void __init_tls(size_t *aux)
T.size += (-T.size - (uintptr_t)T.image) & (T.align-1);
if (T.align < MIN_TLS_ALIGN) T.align = MIN_TLS_ALIGN;
- libc.tls_size = 2*sizeof(void *)+T.size+T.align+sizeof(struct pthread);
+ libc.tls_size = 2*sizeof(void *)+T.size+T.align+sizeof(struct pthread)
if (libc.tls_size > sizeof builtin_tls) {
#ifndef SYS_mmap2