From a1eb8cb5dab06dd23c256d03d82ef6b0efc4b6c6 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Wed, 30 Mar 2011 10:32:45 -0400 Subject: avoid crash on stupid but allowable usage of pthread_mutex_unlock unlocking an unlocked mutex is not UB for robust or error-checking mutexes, so we must avoid calling __pthread_self (which might crash due to lack of thread-register initialization) until after checking that the mutex is locked. --- src/thread/pthread_mutex_unlock.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/thread/pthread_mutex_unlock.c b/src/thread/pthread_mutex_unlock.c index 5855db0b..6c4d7f22 100644 --- a/src/thread/pthread_mutex_unlock.c +++ b/src/thread/pthread_mutex_unlock.c @@ -5,9 +5,11 @@ int pthread_mutex_unlock(pthread_mutex_t *m) pthread_t self; if (m->_m_type != PTHREAD_MUTEX_NORMAL) { + if (!m->_m_lock) + return EPERM; self = __pthread_self(); if ((m->_m_lock&0x1fffffff) != self->tid) - return EPERM; + return EPERM; if ((m->_m_type&3) == PTHREAD_MUTEX_RECURSIVE && --m->_m_count) return 0; if (m->_m_type >= 4) { -- cgit v1.2.1