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| author | Ben Hutchings <ben@decadent.org.uk> | 2021-03-01 18:32:02 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-07 11:25:55 +0100 |
| commit | 69015306e3d079fe2cc5a503c52583eee7a8f450 (patch) | |
| tree | a5314a2d9e35eeeac4e8429680ec25fc369a8d73 /kernel/futex.c | |
| parent | da1b9ad9f05c0c0676055e39756294f3eefbe934 (diff) | |
| download | linux-stable-69015306e3d079fe2cc5a503c52583eee7a8f450.tar.gz linux-stable-69015306e3d079fe2cc5a503c52583eee7a8f450.tar.bz2 linux-stable-69015306e3d079fe2cc5a503c52583eee7a8f450.zip | |
futex: Don't enable IRQs unconditionally in put_pi_state()
From: Dan Carpenter <dan.carpenter@oracle.com>
commit 1e106aa3509b86738769775969822ffc1ec21bf4 upstream.
The exit_pi_state_list() function calls put_pi_state() with IRQs disabled
and is not expecting that IRQs will be enabled inside the function.
Use the _irqsave() variant so that IRQs are restored to the original state
instead of being enabled unconditionally.
Fixes: 153fbd1226fb ("futex: Fix more put_pi_state() vs. exit_pi_state_list() races")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201106085205.GA1159983@mwanda
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel/futex.c')
| -rw-r--r-- | kernel/futex.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/kernel/futex.c b/kernel/futex.c index 855dae277f83..0015c14ac2c0 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -882,10 +882,12 @@ static void put_pi_state(struct futex_pi_state *pi_state) * and has cleaned up the pi_state already */ if (pi_state->owner) { - raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock); + unsigned long flags; + + raw_spin_lock_irqsave(&pi_state->pi_mutex.wait_lock, flags); pi_state_update_owner(pi_state, NULL); rt_mutex_proxy_unlock(&pi_state->pi_mutex); - raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock); + raw_spin_unlock_irqrestore(&pi_state->pi_mutex.wait_lock, flags); } if (current->pi_state_cache) { |