Re: [syzbot] [syzbot] [fs?] general protection fault in iter_file_splice_write

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Subject: [syzbot] [fs?] general protection fault in iter_file_splice_write
Author: lizhi.xu@xxxxxxxxxxxxx

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 33e02dc69afb

diff --git a/fs/netfs/direct_write.c b/fs/netfs/direct_write.c
index 608ba6416919..d74761fb1876 100644
--- a/fs/netfs/direct_write.c
+++ b/fs/netfs/direct_write.c
@@ -69,7 +69,7 @@ static ssize_t netfs_unbuffered_write_iter_locked(struct kiocb *iocb, struct iov
 		 */
 		if (async || user_backed_iter(iter)) {
 			n = netfs_extract_user_iter(iter, len, &wreq->iter, 0);
-			if (n < 0) {
+			if (n <= 0) {
 				ret = n;
 				goto out;
 			}