From be455802bf55a051bb467b22ad26653a0e78bc61 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 15 Feb 2012 12:08:34 +0100 Subject: [PATCH] futex: Cover all PI opcodes with cmpxchg enabled check commit 59263b513c11398cd66a52d4c5b2b118ce1e0359 upstream. Some of the newer futex PI opcodes do not check the cmpxchg enabled variable and call unconditionally into the handling functions. Cover all PI opcodes in a separate check. Signed-off-by: Thomas Gleixner Cc: Peter Zijlstra Cc: Darren Hart Signed-off-by: Greg Kroah-Hartman --- kernel/futex.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/kernel/futex.c b/kernel/futex.c index 6487e4cb9935..a2a01ef0ee3c 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2640,6 +2640,16 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, return -ENOSYS; } + switch (cmd) { + case FUTEX_LOCK_PI: + case FUTEX_UNLOCK_PI: + case FUTEX_TRYLOCK_PI: + case FUTEX_WAIT_REQUEUE_PI: + case FUTEX_CMP_REQUEUE_PI: + if (!futex_cmpxchg_enabled) + return -ENOSYS; + } + switch (cmd) { case FUTEX_WAIT: val3 = FUTEX_BITSET_MATCH_ANY; @@ -2661,16 +2671,13 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, ret = futex_wake_op(uaddr, flags, uaddr2, val, val2, val3); break; case FUTEX_LOCK_PI: - if (futex_cmpxchg_enabled) - ret = futex_lock_pi(uaddr, flags, val, timeout, 0); + ret = futex_lock_pi(uaddr, flags, val, timeout, 0); break; case FUTEX_UNLOCK_PI: - if (futex_cmpxchg_enabled) - ret = futex_unlock_pi(uaddr, flags); + ret = futex_unlock_pi(uaddr, flags); break; case FUTEX_TRYLOCK_PI: - if (futex_cmpxchg_enabled) - ret = futex_lock_pi(uaddr, flags, 0, timeout, 1); + ret = futex_lock_pi(uaddr, flags, 0, timeout, 1); break; case FUTEX_WAIT_REQUEUE_PI: val3 = FUTEX_BITSET_MATCH_ANY; -- 2.39.5