4.20-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 59d49076ae3e6912e6d7df2fd68e2337f3d02036 ]
Fix the refcounting of the authentication keys in the file locking code. The vnode->lock_key member points to a key on which it expects to be holding a ref, but it isn't always given an extra ref, however.
Fixes: 0fafdc9f888b ("afs: Fix file locking") Signed-off-by: David Howells dhowells@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/afs/flock.c | 4 ++-- fs/afs/inode.c | 2 ++ 2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/fs/afs/flock.c b/fs/afs/flock.c index 0568fd9868210..e432bd27a2e7b 100644 --- a/fs/afs/flock.c +++ b/fs/afs/flock.c @@ -208,7 +208,7 @@ void afs_lock_work(struct work_struct *work) /* The new front of the queue now owns the state variables. */ next = list_entry(vnode->pending_locks.next, struct file_lock, fl_u.afs.link); - vnode->lock_key = afs_file_key(next->fl_file); + vnode->lock_key = key_get(afs_file_key(next->fl_file)); vnode->lock_type = (next->fl_type == F_RDLCK) ? AFS_LOCK_READ : AFS_LOCK_WRITE; vnode->lock_state = AFS_VNODE_LOCK_WAITING_FOR_CB; goto again; @@ -413,7 +413,7 @@ static void afs_dequeue_lock(struct afs_vnode *vnode, struct file_lock *fl) /* The new front of the queue now owns the state variables. */ next = list_entry(vnode->pending_locks.next, struct file_lock, fl_u.afs.link); - vnode->lock_key = afs_file_key(next->fl_file); + vnode->lock_key = key_get(afs_file_key(next->fl_file)); vnode->lock_type = (next->fl_type == F_RDLCK) ? AFS_LOCK_READ : AFS_LOCK_WRITE; vnode->lock_state = AFS_VNODE_LOCK_WAITING_FOR_CB; afs_lock_may_be_available(vnode); diff --git a/fs/afs/inode.c b/fs/afs/inode.c index 211343831c304..1a4ce07fb406d 100644 --- a/fs/afs/inode.c +++ b/fs/afs/inode.c @@ -545,6 +545,8 @@ void afs_evict_inode(struct inode *inode) #endif
afs_put_permits(rcu_access_pointer(vnode->permit_cache)); + key_put(vnode->lock_key); + vnode->lock_key = NULL; _leave(""); }