From: Jens Axboe <axboe@kernel.dk>
Date: Wed, 21 Jan 2026 18:48:56 +0000 (-0700)
Subject: io_uring/sync: validate passed in offset
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=649dd18f559891bdafc5532d737c7dfb56060a6d;p=thirdparty%2Fkernel%2Flinux.git

io_uring/sync: validate passed in offset

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>
---

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;