linux-kernel - [PATCH 5.10 517/717] io_uring: fix 0-iov read buffer select

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

Message-Id: <20201228125045.724452992@linuxfoundation.org>
Date:   Mon, 28 Dec 2020 13:48:35 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Pavel Begunkov <asml.silence@...il.com>,
        Jens Axboe <axboe@...nel.dk>
Subject: [PATCH 5.10 517/717] io_uring: fix 0-iov read buffer select

From: Pavel Begunkov <asml.silence@...il.com>

commit dd20166236953c8cd14f4c668bf972af32f0c6be upstream.

Doing vectored buf-select read with 0 iovec passed is meaningless and
utterly broken, forbid it.

Cc: <stable@...r.kernel.org> # 5.7+
Signed-off-by: Pavel Begunkov <asml.silence@...il.com>
Signed-off-by: Jens Axboe <axboe@...nel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 fs/io_uring.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3048,9 +3048,7 @@ static ssize_t io_iov_buffer_select(stru
 		iov[0].iov_len = kbuf->len;
 		return 0;
 	}
-	if (!req->rw.len)
-		return 0;
-	else if (req->rw.len > 1)
+	if (req->rw.len != 1)
 		return -EINVAL;
 
 #ifdef CONFIG_COMPAT