From: Tetsuo Handa Date: Fri, 12 Apr 2019 10:56:39 +0000 (+0900) Subject: udpv6: Check address length before reading address family X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=bddc028a4f2ac8cf4d0cd1c696b5f95d8305a553;p=linux.git udpv6: Check address length before reading address family KMSAN will complain if valid address length passed to udpv6_pre_connect() is shorter than sizeof("struct sockaddr"->sa_family) bytes. (This patch is bogus if it is guaranteed that udpv6_pre_connect() is always called after checking "struct sockaddr"->sa_family. In that case, we want a comment why we don't need to check valid address length here.) Signed-off-by: Tetsuo Handa Acked-by: Song Liu Signed-off-by: David S. Miller --- diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index b444483cdb2b4..622eeaf5732b3 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -1047,6 +1047,8 @@ static void udp_v6_flush_pending_frames(struct sock *sk) static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { + if (addr_len < offsetofend(struct sockaddr, sa_family)) + return -EINVAL; /* The following checks are replicated from __ip6_datagram_connect() * and intended to prevent BPF program called below from accessing * bytes that are out of the bound specified by user in addr_len.