path: root/fs
diff options
authorBenjamin Coddington <bcodding@redhat.com>2017-07-28 12:33:54 -0400
committerAnna Schumaker <Anna.Schumaker@Netapp.com>2017-07-28 15:35:30 -0400
commitb7dbcc0e433f0f61acb89ed9861ec996be4f2b38 (patch)
treecedc255e9890c2060393b1f28cf8db5d57e51151 /fs
parent6ba80d4348bd8cce2a0a6bbc21e5e1e760de42a9 (diff)
NFSv4.1: Fix a race where CB_NOTIFY_LOCK fails to wake a waiter
nfs4_retry_setlk() sets the task's state to TASK_INTERRUPTIBLE within the same region protected by the wait_queue's lock after checking for a notification from CB_NOTIFY_LOCK callback. However, after releasing that lock, a wakeup for that task may race in before the call to freezable_schedule_timeout_interruptible() and set TASK_WAKING, then freezable_schedule_timeout_interruptible() will set the state back to TASK_INTERRUPTIBLE before the task will sleep. The result is that the task will sleep for the entire duration of the timeout. Since we've already set TASK_INTERRUPTIBLE in the locked section, just use freezable_schedule_timout() instead. Fixes: a1d617d8f134 ("nfs: allow blocking locks to be awoken by lock callbacks") Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Diffstat (limited to 'fs')
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 583c2b38c908..93c1d7352238 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -6495,7 +6495,7 @@ nfs4_retry_setlk(struct nfs4_state *state, int cmd, struct file_lock *request)
spin_unlock_irqrestore(&q->lock, flags);
- freezable_schedule_timeout_interruptible(NFS4_LOCK_MAXTIMEOUT);
+ freezable_schedule_timeout(NFS4_LOCK_MAXTIMEOUT);
finish_wait(q, &wait);