[PATCH 5.17 099/146] io_uring: free iovec if file assignment fails

From: Greg Kroah-Hartman
Date: Tue Apr 26 2022 - 05:34:03 EST


From: Jens Axboe <axboe@xxxxxxxxx>

[ Upstream commit 323b190ba2debbcc03c01d2edaf1ec6b43e6ae43 ]

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@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 584b0180f0f4 ("io_uring: move read/write file prep state into actual opcode handler")
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 619c67fd456d..9349d7e0754f 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3622,8 +3622,10 @@ 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) {
@@ -3742,8 +3744,10 @@ 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) {
--
2.35.1