From 323b190ba2debbcc03c01d2edaf1ec6b43e6ae43 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@kernel.dk>
Date: Sat, 16 Apr 2022 21:14:00 -0600
Subject: [PATCH] io_uring: free iovec if file assignment fails
Git-commit: 323b190ba2debbcc03c01d2edaf1ec6b43e6ae43
Patch-mainline: v5.18-rc4
References: bsc#1205205

We just return failure in this case, but we need to release the iovec
first. If we're doing IO with more than FAST_IOV segments, then the
iovec is allocated and must be freed.

Reported-by: syzbot+96b43810dfe9c3bb95ed@syzkaller.appspotmail.com
Fixes: 584b0180f0f4 ("io_uring: move read/write file prep state into actual opcode handler")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
---
 fs/io_uring.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 4479013854d2..24409dd07239 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3832,8 +3832,10 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags)
 		iovec = NULL;
 	}
 	ret = io_rw_init_file(req, FMODE_READ);
-	if (unlikely(ret))
+	if (unlikely(ret)) {
+		kfree(iovec);
 		return ret;
+	}
 	req->result = iov_iter_count(&s->iter);
 
 	if (force_nonblock) {
@@ -3958,8 +3960,10 @@ static int io_write(struct io_kiocb *req, unsigned int issue_flags)
 		iovec = NULL;
 	}
 	ret = io_rw_init_file(req, FMODE_WRITE);
-	if (unlikely(ret))
+	if (unlikely(ret)) {
+		kfree(iovec);
 		return ret;
+	}
 	req->result = iov_iter_count(&s->iter);
 
 	if (force_nonblock) {
-- 
2.35.3