4.4-stable review patch. If anyone has any objections, please let me know.
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From: Miklos Szeredi mszeredi@redhat.com
commit 45ff350bbd9d0f0977ff270a0d427c71520c0c37 upstream.
fuse_dev_release() assumes that it's the only one referencing the fpq->processing list, but that's not true, since fuse_abort_conn() can be doing the same without any serialization between the two.
Fixes: c3696046beb3 ("fuse: separate pqueue for clones") Cc: stable@vger.kernel.org # v4.2 Signed-off-by: Miklos Szeredi mszeredi@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/fuse/dev.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
--- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -2199,9 +2199,15 @@ int fuse_dev_release(struct inode *inode if (fud) { struct fuse_conn *fc = fud->fc; struct fuse_pqueue *fpq = &fud->pq; + LIST_HEAD(to_end);
+ spin_lock(&fpq->lock); WARN_ON(!list_empty(&fpq->io)); - end_requests(fc, &fpq->processing); + list_splice_init(&fpq->processing, &to_end); + spin_unlock(&fpq->lock); + + end_requests(fc, &to_end); + /* Are we the last open device? */ if (atomic_dec_and_test(&fc->dev_count)) { WARN_ON(fc->iq.fasync != NULL);