From: Matthew Leach Date: Tue, 11 Mar 2014 11:58:27 +0000 (+0000) Subject: net: socket: error on a negative msg_namelen X-Git-Tag: v3.14-rc7~10^2~7 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=dbb490b96584;p=linux.git net: socket: error on a negative msg_namelen 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 --- diff --git a/net/socket.c b/net/socket.c index 879933aaed4c..32df5847efa3 100644 --- a/net/socket.c +++ b/net/socket.c @@ -1985,6 +1985,10 @@ 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;