Messages in this thread Patch in this message | | | Date | Wed, 14 Oct 2009 20:11:03 GMT | From | tip-bot for Darren Hart <> | Subject | [tip:core/urgent] futex: Check for NULL keys in match_futex |
| |
Commit-ID: 2bc872036e1c5948b5b02942810bbdd8dbdb9812 Gitweb: http://git.kernel.org/tip/2bc872036e1c5948b5b02942810bbdd8dbdb9812 Author: Darren Hart <dvhltc@us.ibm.com> AuthorDate: Wed, 14 Oct 2009 10:12:39 -0700 Committer: Thomas Gleixner <tglx@linutronix.de> CommitDate: Wed, 14 Oct 2009 22:00:14 +0200
futex: Check for NULL keys in match_futex
If userspace tries to perform a requeue_pi on a non-requeue_pi waiter, it will find the futex_q->requeue_pi_key to be NULL and OOPS.
Check for NULL in match_futex() instead of doing explicit NULL pointer checks on all call sites. While match_futex(NULL, NULL) returning false is a little odd, it's still correct as we expect valid key references.
Signed-off-by: Darren Hart <dvhltc@us.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@elte.hu> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Dinakar Guniguntala <dino@in.ibm.com> CC: John Stultz <johnstul@us.ibm.com> Cc: stable@kernel.org LKML-Reference: <4AD60687.10306@us.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> --- kernel/futex.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-)
diff --git a/kernel/futex.c b/kernel/futex.c index 5c88839..06938e5 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -150,7 +150,8 @@ static struct futex_hash_bucket *hash_futex(union futex_key *key) */ static inline int match_futex(union futex_key *key1, union futex_key *key2) { - return (key1->both.word == key2->both.word + return (key1 && key2 + && key1->both.word == key2->both.word && key1->both.ptr == key2->both.ptr && key1->both.offset == key2->both.offset); }
| |