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authorRich Felker <dalias@aerifal.cx>2019-03-21 13:58:12 -0400
committerRich Felker <dalias@aerifal.cx>2019-03-21 13:58:12 -0400
commit59f88d766263344ce3e124d969ba66720aff4590 (patch)
tree1d7c438347cc69a5e865d404b3b339f74e144044 /src
parent8f12c4e110acb3bbbdc8abfb3a552c3ced718039 (diff)
downloadmusl-59f88d766263344ce3e124d969ba66720aff4590.tar.gz
fix data race choosing next key slot in pthread_key_create
commit 84d061d5a31c9c773e29e1e2b1ffe8cb9557bc58 wrongly moved the access to the global next_key outside of the scope of the lock. the error manifested as spurious failure to find an available key slot under concurrent calls to pthread_key_create, since the stopping condition could be met after only a small number of slots were examined.
Diffstat (limited to 'src')
-rw-r--r--src/thread/pthread_key_create.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/src/thread/pthread_key_create.c b/src/thread/pthread_key_create.c
index 210605c6..d1120941 100644
--- a/src/thread/pthread_key_create.c
+++ b/src/thread/pthread_key_create.c
@@ -22,7 +22,6 @@ weak_alias(dummy_0, __tl_unlock);
int __pthread_key_create(pthread_key_t *k, void (*dtor)(void *))
{
- pthread_key_t j = next_key;
pthread_t self = __pthread_self();
/* This can only happen in the main thread before
@@ -33,6 +32,7 @@ int __pthread_key_create(pthread_key_t *k, void (*dtor)(void *))
if (!dtor) dtor = nodtor;
__pthread_rwlock_wrlock(&key_lock);
+ pthread_key_t j = next_key;
do {
if (!keys[j]) {
keys[next_key = *k = j] = dtor;