[PATCH 6.19 043/781] io_uring/sync: validate passed in offset

Greg Kroah-Hartman
2026-02-25T01:27:34Z

From: Jens Axboe <axboe@kernel.dk>

[ Upstream commit 649dd18f559891bdafc5532d737c7dfb56060a6d ]

Check if the passed in offset is negative once cast to sync->off. This
ensures that -EINVAL is returned for that case, like it would be for
sync_file_range(2).

Fixes: c992fe2925d7 ("io_uring: add fsync support")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
io_uring/sync.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/io_uring/sync.c b/io_uring/sync.c
index cea2d381ffd2a..ab7fa1cd7dd63 100644
--- a/io_uring/sync.c
+++ b/io_uring/sync.c
@@ -62,6 +62,8 @@ int io_fsync_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
return -EINVAL;

sync->off = READ_ONCE(sqe->off);
+ if (sync->off < 0)
+ return -EINVAL;
sync->len = READ_ONCE(sqe->len);
req->flags |= REQ_F_FORCE_ASYNC;
return 0;
--
2.51.0