7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Howells [ Upstream commit 3c30087e27598d9d359763e8be9bd3017fe08348 ] Fix a subrequest ref leak in netfs_unbuffered_write() in the event that subreq->io_iter ends up zero length during preparation. Fixes: a0b4c7a49137e ("netfs: Fix unbuffered/DIO writes to dispatch subrequests in strict sequence") Link: https://sashiko.dev/#/patchset/20260824120224.504575-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260827134304.2075713-6-dhowells@redhat.com Acked-by: Paulo Alcantara cc: Paulo Alcantara cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner (Amutable) Signed-off-by: Sasha Levin --- fs/netfs/direct_write.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/fs/netfs/direct_write.c b/fs/netfs/direct_write.c index e07e7850a5a21..86beeb337ed7f 100644 --- a/fs/netfs/direct_write.c +++ b/fs/netfs/direct_write.c @@ -121,8 +121,14 @@ static int netfs_unbuffered_write(struct netfs_io_request *wreq) } iov_iter_truncate(&subreq->io_iter, wreq->len - wreq->transferred); - if (!iov_iter_count(&subreq->io_iter)) + if (!iov_iter_count(&subreq->io_iter)) { + pr_warn("netfs: Unexpected zero-length iterator R=%08x\n", + wreq->debug_id); + __set_bit(NETFS_SREQ_FAILED, &subreq->flags); + netfs_write_subrequest_terminated(subreq, -EIO); + wreq->error = -EIO; break; + } subreq->len = netfs_limit_iter(&subreq->io_iter, 0, stream->sreq_max_len, -- 2.53.0