From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Wong , Dan Carpenter , Eric Dumazet , "David S. Miller" Subject: [PATCH 3.10 22/58] net: clamp ->msg_namelen instead of returning an error Date: Fri, 6 Dec 2013 13:51:53 -0800 Message-Id: <20131206214846.976397916@linuxfoundation.org> In-Reply-To: <20131206214844.906193530@linuxfoundation.org> References: <20131206214844.906193530@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter [ Upstream commit db31c55a6fb245fdbb752a2ca4aefec89afabb06 ] If kmsg->msg_namelen > sizeof(struct sockaddr_storage) then in the original code that would lead to memory corruption in the kernel if you had audit configured. If you didn't have audit configured it was harmless. There are some programs such as beta versions of Ruby which use too large of a buffer and returning an error code breaks them. We should clamp the ->msg_namelen value instead. Fixes: 1661bf364ae9 ("net: heap overflow in __audit_sockaddr()") Reported-by: Eric Wong Signed-off-by: Dan Carpenter Tested-by: Eric Wong Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/compat.c | 2 +- net/socket.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) --- a/net/compat.c +++ b/net/compat.c @@ -72,7 +72,7 @@ int get_compat_msghdr(struct msghdr *kms __get_user(kmsg->msg_flags, &umsg->msg_flags)) return -EFAULT; if (kmsg->msg_namelen > sizeof(struct sockaddr_storage)) - return -EINVAL; + kmsg->msg_namelen = sizeof(struct sockaddr_storage); kmsg->msg_name = compat_ptr(tmp1); kmsg->msg_iov = compat_ptr(tmp2); kmsg->msg_control = compat_ptr(tmp3); --- a/net/socket.c +++ b/net/socket.c @@ -1965,7 +1965,7 @@ static int copy_msghdr_from_user(struct if (copy_from_user(kmsg, umsg, sizeof(struct msghdr))) return -EFAULT; if (kmsg->msg_namelen > sizeof(struct sockaddr_storage)) - return -EINVAL; + kmsg->msg_namelen = sizeof(struct sockaddr_storage); return 0; }