From f54ba391d88f5a5d032175b4c308c176e34b80b7 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Fri, 8 Mar 2019 08:57:26 +0100 Subject: xsk: fix to reject invalid flags in xsk_bind MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Passing a non-existing flag in the sxdp_flags member of struct sockaddr_xdp was, incorrectly, silently ignored. This patch addresses that behavior, and rejects any non-existing flags. We have examined existing user space code, and to our best knowledge, no one is relying on the current incorrect behavior. AF_XDP is still in its infancy, so from our perspective, the risk of breakage is very low, and addressing this problem now is important. Fixes: 965a99098443 ("xsk: add support for bind for Rx") Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann --- net/xdp/xsk.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'net/xdp/xsk.c') diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 6697084e3fdf..a14e8864e4fa 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -407,6 +407,10 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) if (sxdp->sxdp_family != AF_XDP) return -EINVAL; + flags = sxdp->sxdp_flags; + if (flags & ~(XDP_SHARED_UMEM | XDP_COPY | XDP_ZEROCOPY)) + return -EINVAL; + mutex_lock(&xs->mutex); if (xs->dev) { err = -EBUSY; @@ -425,7 +429,6 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) } qid = sxdp->sxdp_queue_id; - flags = sxdp->sxdp_flags; if (flags & XDP_SHARED_UMEM) { struct xdp_sock *umem_xs; -- cgit v1.2.3-59-g8ed1b