Re: [syzbot] [netfs?] KASAN: slab-use-after-free Read in netfs_unbuffered_write

David Howells <[email protected]> Wed, 24 Jun 2026 12:04:40 +0100
Newsgroups dev.linux.lists.netfs,org.kernel.vger.linux-fsdevel,org.kernel.vger.linux-kernel
Organization Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903
Message-ID <[email protected]>
#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 8fde5d1d47f6

diff --git a/fs/netfs/direct_write.c b/fs/netfs/direct_write.c
index 25f8ceb15fad..1ff1789016b8 100644
--- a/fs/netfs/direct_write.c
+++ b/fs/netfs/direct_write.c
@@ -190,12 +190,6 @@ static int netfs_unbuffered_write(struct netfs_io_request *wreq)
 			stream->prepare_write(subreq);
 			__set_bit(NETFS_SREQ_IN_PROGRESS, &subreq->flags);
 			netfs_stat(&netfs_n_wh_retry_write_subreq);
-		} else {
-			struct iov_iter source;
-
-			netfs_reset_iter(subreq);
-			source = subreq->io_iter;
-			netfs_reissue_write(stream, subreq, &source);
 		}
 	}