linux-kernel - [PATCH 2/2] io_uring: fix openat/statx's filename leak

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Sat,  8 Feb 2020 13:28:03 +0300
From:   Pavel Begunkov <asml.silence@...il.com>
To:     Jens Axboe <axboe@...nel.dk>, io-uring@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH 2/2] io_uring: fix openat/statx's filename leak

As in the previous patch, make openat*_prep() and statx_prep() to
handle double prepartion to avoid resource leakage.

Signed-off-by: Pavel Begunkov <asml.silence@...il.com>
---
 fs/io_uring.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index f5aa2fdccf7a..c3bac9d850a5 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2536,6 +2536,8 @@ static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 		return -EINVAL;
 	if (sqe->flags & IOSQE_FIXED_FILE)
 		return -EINVAL;
+	if (req->flags & REQ_F_NEED_CLEANUP)
+		return 0;
 
 	req->open.dfd = READ_ONCE(sqe->fd);
 	req->open.how.mode = READ_ONCE(sqe->len);
@@ -2564,6 +2566,8 @@ static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 		return -EINVAL;
 	if (sqe->flags & IOSQE_FIXED_FILE)
 		return -EINVAL;
+	if (req->flags & REQ_F_NEED_CLEANUP)
+		return 0;
 
 	req->open.dfd = READ_ONCE(sqe->fd);
 	fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
@@ -2763,6 +2767,8 @@ static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 		return -EINVAL;
 	if (sqe->flags & IOSQE_FIXED_FILE)
 		return -EINVAL;
+	if (req->flags & REQ_F_NEED_CLEANUP)
+		return 0;
 
 	req->open.dfd = READ_ONCE(sqe->fd);
 	req->open.mask = READ_ONCE(sqe->len);
-- 
2.24.0