https://github.com/torvalds/linux
Revision 88a8121dc1d3d0dbddd411b79ed236b6b6ea415c authored by Nicolas Dichtel on 17 January 2019, 10:27:22 UTC, committed by David S. Miller on 17 January 2019, 23:54:45 UTC
Since commit cb9f1b783850, scapy (which uses an AF_PACKET socket in SOCK_RAW mode) is unable to send a basic icmp packet over a sit tunnel: Here is a example of the setup: $ ip link set ntfp2 up $ ip addr add 10.125.0.1/24 dev ntfp2 $ ip tunnel add tun1 mode sit ttl 64 local 10.125.0.1 remote 10.125.0.2 dev ntfp2 $ ip addr add fd00:cafe:cafe::1/128 dev tun1 $ ip link set dev tun1 up $ ip route add fd00:200::/64 dev tun1 $ scapy >>> p = [] >>> p += IPv6(src='fd00:100::1', dst='fd00:200::1')/ICMPv6EchoRequest() >>> send(p, count=1, inter=0.1) >>> quit() $ ip -s link ls dev tun1 | grep -A1 "TX.*errors" TX: bytes packets errors dropped carrier collsns 0 0 1 0 0 0 The problem is that the network offset is set to the hard_header_len of the output device (tun1, ie 14 + 20) and in our case, because the packet is small (48 bytes) the pskb_inet_may_pull() fails (it tries to pull 40 bytes (ipv6 header) starting from the network offset). This problem is more generally related to device with variable hard header length. To avoid a too intrusive patch in the current release, a (ugly) workaround is proposed in this patch. It has to be cleaned up in net-next. Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=993675a3100b1 Link: http://patchwork.ozlabs.org/patch/1024489/ Fixes: cb9f1b783850 ("ip: validate header length on virtual device xmit") CC: Willem de Bruijn <willemb@google.com> CC: Maxim Mikityanskiy <maximmi@mellanox.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Tip revision: 88a8121dc1d3d0dbddd411b79ed236b6b6ea415c authored by Nicolas Dichtel on 17 January 2019, 10:27:22 UTC
af_packet: fix raw sockets over 6in4 tunnel
af_packet: fix raw sockets over 6in4 tunnel
Tip revision: 88a8121
File | Mode | Size |
---|---|---|
Kconfig | -rw-r--r-- | 63.7 KB |
Makefile | -rw-r--r-- | 1.2 KB |
calibrate.c | -rw-r--r-- | 8.6 KB |
do_mounts.c | -rw-r--r-- | 15.1 KB |
do_mounts.h | -rw-r--r-- | 1.1 KB |
do_mounts_initrd.c | -rw-r--r-- | 3.5 KB |
do_mounts_md.c | -rw-r--r-- | 7.9 KB |
do_mounts_rd.c | -rw-r--r-- | 8.1 KB |
init_task.c | -rw-r--r-- | 5.2 KB |
initramfs.c | -rw-r--r-- | 13.7 KB |
main.c | -rw-r--r-- | 28.4 KB |
noinitramfs.c | -rw-r--r-- | 1.5 KB |
version.c | -rw-r--r-- | 1.2 KB |
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