From: Lee Jones <lee@kernel.org> stable inclusion from stable-v5.10.134 commit 2ee0cab11f6626071f8a64c7792406dabdd94c8d category: bugfix bugzilla: 187845, https://gitee.com/src-openeuler/kernel/issues/I5UDNW CVE: CVE-2022-20409 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- This issue is conceptually identical to the one fixed in 29f077d07051 ("io_uring: always use original task when preparing req identity"), so rather than reinvent the wheel, I'm shamelessly quoting the commit message from that patch - thanks Jens: "If the ring is setup with IORING_SETUP_IOPOLL and we have more than one task doing submissions on a ring, we can up in a situation where we assign the context from the current task rather than the request originator. Always use req->task rather than assume it's the same as current. No upstream patch exists for this issue, as only older kernels with the non-native workers have this problem." Cc: Jens Axboe <axboe@kernel.dk> Cc: Pavel Begunkov <asml.silence@gmail.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: io-uring@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Fixes: 5c3462cfd123b ("io_uring: store io_identity in io_uring_task") Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- fs/io_uring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 257e4af176e6..71cabd60a01d 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1325,7 +1325,7 @@ static void io_req_clean_work(struct io_kiocb *req) */ static bool io_identity_cow(struct io_kiocb *req) { - struct io_uring_task *tctx = current->io_uring; + struct io_uring_task *tctx = req->task->io_uring; const struct cred *creds = NULL; struct io_identity *id; -- 2.20.1