diff options
| author | Arjun Roy <arjunroy@google.com> | 2020-02-25 23:38:54 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-02-27 07:24:22 +0300 |
| commit | 0b7f41f68710ccbf7d029c749616e5d26ae8f74d (patch) | |
| tree | b9873f953bf4389af332e307fa55efa8d613f11e /net | |
| parent | ebb4a4bf76f164457184a3f43ebc1552416bc823 (diff) | |
| download | linux-0b7f41f68710ccbf7d029c749616e5d26ae8f74d.tar.xz | |
tcp-zerocopy: Update returned getsockopt() optlen.
TCP receive zerocopy currently does not update the returned optlen for
getsockopt() if the user passed in a larger than expected value.
Thus, userspace cannot properly determine if all the fields are set in
the passed-in struct. This patch sets the optlen for this case before
returning, in keeping with the expected operation of getsockopt().
Fixes: c8856c051454 ("tcp-zerocopy: Return inq along with tcp receive zerocopy.")
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/tcp.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 1b685485a5b5..48aa457a9516 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3669,8 +3669,11 @@ static int do_tcp_getsockopt(struct sock *sk, int level, return -EFAULT; if (len < offsetofend(struct tcp_zerocopy_receive, length)) return -EINVAL; - if (len > sizeof(zc)) + if (len > sizeof(zc)) { len = sizeof(zc); + if (put_user(len, optlen)) + return -EFAULT; + } if (copy_from_user(&zc, optval, len)) return -EFAULT; lock_sock(sk); |