From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Matthew Leach , "David S. Miller" , Kamal Mostafa Subject: [PATCH 3.8 008/133] net: socket: error on a negative msg_namelen Date: Tue, 22 Apr 2014 13:12:26 -0700 Message-Id: <1398197671-12786-9-git-send-email-kamal@canonical.com> In-Reply-To: <1398197671-12786-1-git-send-email-kamal@canonical.com> References: <1398197671-12786-1-git-send-email-kamal@canonical.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.8.13.22 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Matthew Leach [ Upstream commit dbb490b96584d4e958533fb637f08b557f505657 ] When copying in a struct msghdr from the user, if the user has set the msg_namelen parameter to a negative value it gets clamped to a valid size due to a comparison between signed and unsigned values. Ensure the syscall errors when the user passes in a negative value. Signed-off-by: Matthew Leach Signed-off-by: David S. Miller Signed-off-by: Kamal Mostafa --- net/socket.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/socket.c b/net/socket.c index 57d7a85..17a8cdb 100644 --- a/net/socket.c +++ b/net/socket.c @@ -1988,6 +1988,10 @@ static int copy_msghdr_from_user(struct msghdr *kmsg, { if (copy_from_user(kmsg, umsg, sizeof(struct msghdr))) return -EFAULT; + + if (kmsg->msg_namelen < 0) + return -EINVAL; + if (kmsg->msg_namelen > sizeof(struct sockaddr_storage)) kmsg->msg_namelen = sizeof(struct sockaddr_storage); return 0; -- 1.9.1