ip: validate header length on virtual device xmit
[ Upstream commit cb9f1b783850b14cbd7f87d061d784a666dfba1f ]
KMSAN detected read beyond end of buffer in vti and sit devices when
passing truncated packets with PF_PACKET. The issue affects additional
ip tunnel devices.
Extend commit 76c0ddd8c3a6 ("ip6_tunnel: be careful when accessing the
inner header") and commit ccfec9e5cb2d ("ip_tunnel: be careful when
accessing the inner header").
Move the check to a separate helper and call at the start of each
ndo_start_xmit function in net/ipv4 and net/ipv6.
Minor changes:
- convert dev_kfree_skb to kfree_skb on error path,
as dev_kfree_skb calls consume_skb which is not for error paths.
- use pskb_network_may_pull even though that is pedantic here,
as the same as pskb_may_pull for devices without llheaders.
- do not cache ipv6 hdrs if used only once
(unsafe across pskb_may_pull, was more relevant to earlier patch)
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit cde81154f86e36df0fad21c23976cc8b80c01600)
[vegard: drop changes to ip6erspan_tunnel_xmit(), which doesn't exist
in 4.14 due to missing commit 5a963eb61b7c39e6c422b6e48619d19d04719358
("ip6_gre: Add ERSPAN native tunnel support") from 4.16]
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
12 files changed