From e0fecb289ad3fd2245cdc50bf450b97fcca39884 Mon Sep 17 00:00:00 2001 From: Arjun Roy Date: Thu, 10 Dec 2020 11:16:03 -0800 Subject: [PATCH] tcp: correctly handle increased zerocopy args struct size A prior patch increased the size of struct tcp_zerocopy_receive but did not update do_tcp_getsockopt() handling to properly account for this. This patch simply reintroduces content erroneously cut from the referenced prior patch that handles the new struct size. Fixes: 18fb76ed5386 ("net-zerocopy: Copy straggler unaligned data for TCP Rx. zerocopy.") Signed-off-by: Arjun Roy Signed-off-by: Eric Dumazet Signed-off-by: Soheil Hassas Yeganeh Signed-off-by: David S. Miller --- net/ipv4/tcp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 3c99d48b65d8..ed42d2193c5c 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4082,7 +4082,7 @@ static int do_tcp_getsockopt(struct sock *sk, int level, } #ifdef CONFIG_MMU case TCP_ZEROCOPY_RECEIVE: { - struct tcp_zerocopy_receive zc; + struct tcp_zerocopy_receive zc = {}; int err; if (get_user(len, optlen)) @@ -4099,7 +4099,7 @@ static int do_tcp_getsockopt(struct sock *sk, int level, lock_sock(sk); err = tcp_zerocopy_receive(sk, &zc); release_sock(sk); - if (len == sizeof(zc)) + if (len >= offsetofend(struct tcp_zerocopy_receive, err)) goto zerocopy_rcv_sk_err; switch (len) { case offsetofend(struct tcp_zerocopy_receive, err):