linux.git/net/ipv6/ip6_offload.c, branch v4.20 Linux kernel source tree gso_segment: Reset skb->mac_len after modifying network header 2018-09-13T19:09:32+00:00 Toke Høiland-Jørgensen toke@toke.dk 2018-09-13T14:43:07+00:00 c56cae23c6b167acc68043c683c4573b80cbcc2c When splitting a GSO segment that consists of encapsulated packets, the skb->mac_len of the segments can end up being set wrong, causing packet drops in particular when using act_mirred and ifb interfaces in combination with a qdisc that splits GSO packets. This happens because at the time skb_segment() is called, network_header will point to the inner header, throwing off the calculation in skb_reset_mac_len(). The network_header is subsequently adjust by the outer IP gso_segment handlers, but they don't set the mac_len. Fix this by adding skb_reset_mac_len() calls to both the IPv4 and IPv6 gso_segment handlers, after they modify the network_header. Many thanks to Eric Dumazet for his help in identifying the cause of the bug. Acked-by: Dave Taht <dave.taht@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk> Signed-off-by: David S. Miller <davem@davemloft.net> 
When splitting a GSO segment that consists of encapsulated packets, the
skb->mac_len of the segments can end up being set wrong, causing packet
drops in particular when using act_mirred and ifb interfaces in
combination with a qdisc that splits GSO packets.

This happens because at the time skb_segment() is called, network_header
will point to the inner header, throwing off the calculation in
skb_reset_mac_len(). The network_header is subsequently adjust by the
outer IP gso_segment handlers, but they don't set the mac_len.

Fix this by adding skb_reset_mac_len() calls to both the IPv4 and IPv6
gso_segment handlers, after they modify the network_header.

Many thanks to Eric Dumazet for his help in identifying the cause of
the bug.

Acked-by: Dave Taht <dave.taht@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: Convert GRO SKB handling to list_head. 2018-06-26T02:33:04+00:00 David Miller davem@davemloft.net 2018-06-24T05:13:49+00:00 d4546c2509b1e9cd082e3682dcec98472e37ee5a Manage pending per-NAPI GRO packets via list_head. Return an SKB pointer from the GRO receive handlers. When GRO receive handlers return non-NULL, it means that this SKB needs to be completed at this time and removed from the NAPI queue. Several operations are greatly simplified by this transformation, especially timing out the oldest SKB in the list when gro_count exceeds MAX_GRO_SKBS, and napi_gro_flush() which walks the queue in reverse order. Signed-off-by: David S. Miller <davem@davemloft.net> 
Manage pending per-NAPI GRO packets via list_head.

Return an SKB pointer from the GRO receive handlers.  When GRO receive
handlers return non-NULL, it means that this SKB needs to be completed
at this time and removed from the NAPI queue.

Several operations are greatly simplified by this transformation,
especially timing out the oldest SKB in the list when gro_count
exceeds MAX_GRO_SKBS, and napi_gro_flush() which walks the queue
in reverse order.

Signed-off-by: David S. Miller <davem@davemloft.net>
udp: add udp gso 2018-04-26T19:07:42+00:00 Willem de Bruijn willemb@google.com 2018-04-26T17:42:16+00:00 ee80d1ebe5ba7f4bd74959c873119175a4fc08d3 Implement generic segmentation offload support for udp datagrams. A follow-up patch adds support to the protocol stack to generate such packets. UDP GSO is not UFO. UFO fragments a single large datagram. GSO splits a large payload into a number of discrete UDP datagrams. The implementation adds a GSO type SKB_UDP_GSO_L4 to differentiate it from UFO (SKB_UDP_GSO). IPPROTO_UDPLITE is excluded, as that protocol has no gso handler registered. [ Export __udp_gso_segment for ipv6. -DaveM ] Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Implement generic segmentation offload support for udp datagrams. A
follow-up patch adds support to the protocol stack to generate such
packets.

UDP GSO is not UFO. UFO fragments a single large datagram. GSO splits
a large payload into a number of discrete UDP datagrams.

The implementation adds a GSO type SKB_UDP_GSO_L4 to differentiate it
from UFO (SKB_UDP_GSO).

IPPROTO_UDPLITE is excluded, as that protocol has no gso handler
registered.

[ Export __udp_gso_segment for ipv6. -DaveM ]

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
gso: fix payload length when gso_size is zero 2017-10-08T17:12:15+00:00 Alexey Kodanev alexey.kodanev@oracle.com 2017-10-06T16:02:35+00:00 3d0241d57c7b25bb75ac9d7a62753642264fdbce When gso_size reset to zero for the tail segment in skb_segment(), later in ipv6_gso_segment(), __skb_udp_tunnel_segment() and gre_gso_segment() we will get incorrect results (payload length, pcsum) for that segment. inet_gso_segment() already has a check for gso_size before calculating payload. The issue was found with LTP vxlan & gre tests over ixgbe NIC. Fixes: 07b26c9454a2 ("gso: Support partial splitting at the frag_list pointer") Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com> Acked-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
When gso_size reset to zero for the tail segment in skb_segment(), later
in ipv6_gso_segment(), __skb_udp_tunnel_segment() and gre_gso_segment()
we will get incorrect results (payload length, pcsum) for that segment.
inet_gso_segment() already has a check for gso_size before calculating
payload.

The issue was found with LTP vxlan & gre tests over ixgbe NIC.

Fixes: 07b26c9454a2 ("gso: Support partial splitting at the frag_list pointer")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6: Fix leak in ipv6_gso_segment(). 2017-06-05T01:41:10+00:00 David S. Miller davem@davemloft.net 2017-06-05T01:41:10+00:00 e3e86b5119f81e5e2499bea7ea1ebe8ac6aab789 If ip6_find_1stfragopt() fails and we return an error we have to free up 'segs' because nobody else is going to. Fixes: 2423496af35d ("ipv6: Prevent overrun when parsing v6 header options") Reported-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net> 
If ip6_find_1stfragopt() fails and we return an error we have to free
up 'segs' because nobody else is going to.

Fixes: 2423496af35d ("ipv6: Prevent overrun when parsing v6 header options")
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6: Check ip6_find_1stfragopt() return value properly. 2017-05-18T02:54:11+00:00 David S. Miller davem@davemloft.net 2017-05-18T02:54:11+00:00 7dd7eb9513bd02184d45f000ab69d78cb1fa1531 Do not use unsigned variables to see if it returns a negative error or not. Fixes: 2423496af35d ("ipv6: Prevent overrun when parsing v6 header options") Reported-by: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: David S. Miller <davem@davemloft.net> 
Do not use unsigned variables to see if it returns a negative
error or not.

Fixes: 2423496af35d ("ipv6: Prevent overrun when parsing v6 header options")
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6: Prevent overrun when parsing v6 header options 2017-05-17T18:55:59+00:00 Craig Gallek kraig@google.com 2017-05-16T18:36:23+00:00 2423496af35d94a87156b063ea5cedffc10a70a1 The KASAN warning repoted below was discovered with a syzkaller program. The reproducer is basically: int s = socket(AF_INET6, SOCK_RAW, NEXTHDR_HOP); send(s, &one_byte_of_data, 1, MSG_MORE); send(s, &more_than_mtu_bytes_data, 2000, 0); The socket() call sets the nexthdr field of the v6 header to NEXTHDR_HOP, the first send call primes the payload with a non zero byte of data, and the second send call triggers the fragmentation path. The fragmentation code tries to parse the header options in order to figure out where to insert the fragment option. Since nexthdr points to an invalid option, the calculation of the size of the network header can made to be much larger than the linear section of the skb and data is read outside of it. This fix makes ip6_find_1stfrag return an error if it detects running out-of-bounds. [ 42.361487] ================================================================== [ 42.364412] BUG: KASAN: slab-out-of-bounds in ip6_fragment+0x11c8/0x3730 [ 42.365471] Read of size 840 at addr ffff88000969e798 by task ip6_fragment-oo/3789 [ 42.366469] [ 42.366696] CPU: 1 PID: 3789 Comm: ip6_fragment-oo Not tainted 4.11.0+ #41 [ 42.367628] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1ubuntu1 04/01/2014 [ 42.368824] Call Trace: [ 42.369183] dump_stack+0xb3/0x10b [ 42.369664] print_address_description+0x73/0x290 [ 42.370325] kasan_report+0x252/0x370 [ 42.370839] ? ip6_fragment+0x11c8/0x3730 [ 42.371396] check_memory_region+0x13c/0x1a0 [ 42.371978] memcpy+0x23/0x50 [ 42.372395] ip6_fragment+0x11c8/0x3730 [ 42.372920] ? nf_ct_expect_unregister_notifier+0x110/0x110 [ 42.373681] ? ip6_copy_metadata+0x7f0/0x7f0 [ 42.374263] ? ip6_forward+0x2e30/0x2e30 [ 42.374803] ip6_finish_output+0x584/0x990 [ 42.375350] ip6_output+0x1b7/0x690 [ 42.375836] ? ip6_finish_output+0x990/0x990 [ 42.376411] ? ip6_fragment+0x3730/0x3730 [ 42.376968] ip6_local_out+0x95/0x160 [ 42.377471] ip6_send_skb+0xa1/0x330 [ 42.377969] ip6_push_pending_frames+0xb3/0xe0 [ 42.378589] rawv6_sendmsg+0x2051/0x2db0 [ 42.379129] ? rawv6_bind+0x8b0/0x8b0 [ 42.379633] ? _copy_from_user+0x84/0xe0 [ 42.380193] ? debug_check_no_locks_freed+0x290/0x290 [ 42.380878] ? ___sys_sendmsg+0x162/0x930 [ 42.381427] ? rcu_read_lock_sched_held+0xa3/0x120 [ 42.382074] ? sock_has_perm+0x1f6/0x290 [ 42.382614] ? ___sys_sendmsg+0x167/0x930 [ 42.383173] ? lock_downgrade+0x660/0x660 [ 42.383727] inet_sendmsg+0x123/0x500 [ 42.384226] ? inet_sendmsg+0x123/0x500 [ 42.384748] ? inet_recvmsg+0x540/0x540 [ 42.385263] sock_sendmsg+0xca/0x110 [ 42.385758] SYSC_sendto+0x217/0x380 [ 42.386249] ? SYSC_connect+0x310/0x310 [ 42.386783] ? __might_fault+0x110/0x1d0 [ 42.387324] ? lock_downgrade+0x660/0x660 [ 42.387880] ? __fget_light+0xa1/0x1f0 [ 42.388403] ? __fdget+0x18/0x20 [ 42.388851] ? sock_common_setsockopt+0x95/0xd0 [ 42.389472] ? SyS_setsockopt+0x17f/0x260 [ 42.390021] ? entry_SYSCALL_64_fastpath+0x5/0xbe [ 42.390650] SyS_sendto+0x40/0x50 [ 42.391103] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.391731] RIP: 0033:0x7fbbb711e383 [ 42.392217] RSP: 002b:00007ffff4d34f28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 42.393235] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbbb711e383 [ 42.394195] RDX: 0000000000001000 RSI: 00007ffff4d34f60 RDI: 0000000000000003 [ 42.395145] RBP: 0000000000000046 R08: 00007ffff4d34f40 R09: 0000000000000018 [ 42.396056] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000400aad [ 42.396598] R13: 0000000000000066 R14: 00007ffff4d34ee0 R15: 00007fbbb717af00 [ 42.397257] [ 42.397411] Allocated by task 3789: [ 42.397702] save_stack_trace+0x16/0x20 [ 42.398005] save_stack+0x46/0xd0 [ 42.398267] kasan_kmalloc+0xad/0xe0 [ 42.398548] kasan_slab_alloc+0x12/0x20 [ 42.398848] __kmalloc_node_track_caller+0xcb/0x380 [ 42.399224] __kmalloc_reserve.isra.32+0x41/0xe0 [ 42.399654] __alloc_skb+0xf8/0x580 [ 42.400003] sock_wmalloc+0xab/0xf0 [ 42.400346] __ip6_append_data.isra.41+0x2472/0x33d0 [ 42.400813] ip6_append_data+0x1a8/0x2f0 [ 42.401122] rawv6_sendmsg+0x11ee/0x2db0 [ 42.401505] inet_sendmsg+0x123/0x500 [ 42.401860] sock_sendmsg+0xca/0x110 [ 42.402209] ___sys_sendmsg+0x7cb/0x930 [ 42.402582] __sys_sendmsg+0xd9/0x190 [ 42.402941] SyS_sendmsg+0x2d/0x50 [ 42.403273] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.403718] [ 42.403871] Freed by task 1794: [ 42.404146] save_stack_trace+0x16/0x20 [ 42.404515] save_stack+0x46/0xd0 [ 42.404827] kasan_slab_free+0x72/0xc0 [ 42.405167] kfree+0xe8/0x2b0 [ 42.405462] skb_free_head+0x74/0xb0 [ 42.405806] skb_release_data+0x30e/0x3a0 [ 42.406198] skb_release_all+0x4a/0x60 [ 42.406563] consume_skb+0x113/0x2e0 [ 42.406910] skb_free_datagram+0x1a/0xe0 [ 42.407288] netlink_recvmsg+0x60d/0xe40 [ 42.407667] sock_recvmsg+0xd7/0x110 [ 42.408022] ___sys_recvmsg+0x25c/0x580 [ 42.408395] __sys_recvmsg+0xd6/0x190 [ 42.408753] SyS_recvmsg+0x2d/0x50 [ 42.409086] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.409513] [ 42.409665] The buggy address belongs to the object at ffff88000969e780 [ 42.409665] which belongs to the cache kmalloc-512 of size 512 [ 42.410846] The buggy address is located 24 bytes inside of [ 42.410846] 512-byte region [ffff88000969e780, ffff88000969e980) [ 42.411941] The buggy address belongs to the page: [ 42.412405] page:ffffea000025a780 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 42.413298] flags: 0x100000000008100(slab|head) [ 42.413729] raw: 0100000000008100 0000000000000000 0000000000000000 00000001800c000c [ 42.414387] raw: ffffea00002a9500 0000000900000007 ffff88000c401280 0000000000000000 [ 42.415074] page dumped because: kasan: bad access detected [ 42.415604] [ 42.415757] Memory state around the buggy address: [ 42.416222] ffff88000969e880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 42.416904] ffff88000969e900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 42.417591] >ffff88000969e980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 42.418273] ^ [ 42.418588] ffff88000969ea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.419273] ffff88000969ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.419882] ================================================================== Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Craig Gallek <kraig@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
The KASAN warning repoted below was discovered with a syzkaller
program.  The reproducer is basically:
  int s = socket(AF_INET6, SOCK_RAW, NEXTHDR_HOP);
  send(s, &one_byte_of_data, 1, MSG_MORE);
  send(s, &more_than_mtu_bytes_data, 2000, 0);

The socket() call sets the nexthdr field of the v6 header to
NEXTHDR_HOP, the first send call primes the payload with a non zero
byte of data, and the second send call triggers the fragmentation path.

The fragmentation code tries to parse the header options in order
to figure out where to insert the fragment option.  Since nexthdr points
to an invalid option, the calculation of the size of the network header
can made to be much larger than the linear section of the skb and data
is read outside of it.

This fix makes ip6_find_1stfrag return an error if it detects
running out-of-bounds.

[   42.361487] ==================================================================
[   42.364412] BUG: KASAN: slab-out-of-bounds in ip6_fragment+0x11c8/0x3730
[   42.365471] Read of size 840 at addr ffff88000969e798 by task ip6_fragment-oo/3789
[   42.366469]
[   42.366696] CPU: 1 PID: 3789 Comm: ip6_fragment-oo Not tainted 4.11.0+ #41
[   42.367628] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1ubuntu1 04/01/2014
[   42.368824] Call Trace:
[   42.369183]  dump_stack+0xb3/0x10b
[   42.369664]  print_address_description+0x73/0x290
[   42.370325]  kasan_report+0x252/0x370
[   42.370839]  ? ip6_fragment+0x11c8/0x3730
[   42.371396]  check_memory_region+0x13c/0x1a0
[   42.371978]  memcpy+0x23/0x50
[   42.372395]  ip6_fragment+0x11c8/0x3730
[   42.372920]  ? nf_ct_expect_unregister_notifier+0x110/0x110
[   42.373681]  ? ip6_copy_metadata+0x7f0/0x7f0
[   42.374263]  ? ip6_forward+0x2e30/0x2e30
[   42.374803]  ip6_finish_output+0x584/0x990
[   42.375350]  ip6_output+0x1b7/0x690
[   42.375836]  ? ip6_finish_output+0x990/0x990
[   42.376411]  ? ip6_fragment+0x3730/0x3730
[   42.376968]  ip6_local_out+0x95/0x160
[   42.377471]  ip6_send_skb+0xa1/0x330
[   42.377969]  ip6_push_pending_frames+0xb3/0xe0
[   42.378589]  rawv6_sendmsg+0x2051/0x2db0
[   42.379129]  ? rawv6_bind+0x8b0/0x8b0
[   42.379633]  ? _copy_from_user+0x84/0xe0
[   42.380193]  ? debug_check_no_locks_freed+0x290/0x290
[   42.380878]  ? ___sys_sendmsg+0x162/0x930
[   42.381427]  ? rcu_read_lock_sched_held+0xa3/0x120
[   42.382074]  ? sock_has_perm+0x1f6/0x290
[   42.382614]  ? ___sys_sendmsg+0x167/0x930
[   42.383173]  ? lock_downgrade+0x660/0x660
[   42.383727]  inet_sendmsg+0x123/0x500
[   42.384226]  ? inet_sendmsg+0x123/0x500
[   42.384748]  ? inet_recvmsg+0x540/0x540
[   42.385263]  sock_sendmsg+0xca/0x110
[   42.385758]  SYSC_sendto+0x217/0x380
[   42.386249]  ? SYSC_connect+0x310/0x310
[   42.386783]  ? __might_fault+0x110/0x1d0
[   42.387324]  ? lock_downgrade+0x660/0x660
[   42.387880]  ? __fget_light+0xa1/0x1f0
[   42.388403]  ? __fdget+0x18/0x20
[   42.388851]  ? sock_common_setsockopt+0x95/0xd0
[   42.389472]  ? SyS_setsockopt+0x17f/0x260
[   42.390021]  ? entry_SYSCALL_64_fastpath+0x5/0xbe
[   42.390650]  SyS_sendto+0x40/0x50
[   42.391103]  entry_SYSCALL_64_fastpath+0x1f/0xbe
[   42.391731] RIP: 0033:0x7fbbb711e383
[   42.392217] RSP: 002b:00007ffff4d34f28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[   42.393235] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbbb711e383
[   42.394195] RDX: 0000000000001000 RSI: 00007ffff4d34f60 RDI: 0000000000000003
[   42.395145] RBP: 0000000000000046 R08: 00007ffff4d34f40 R09: 0000000000000018
[   42.396056] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000400aad
[   42.396598] R13: 0000000000000066 R14: 00007ffff4d34ee0 R15: 00007fbbb717af00
[   42.397257]
[   42.397411] Allocated by task 3789:
[   42.397702]  save_stack_trace+0x16/0x20
[   42.398005]  save_stack+0x46/0xd0
[   42.398267]  kasan_kmalloc+0xad/0xe0
[   42.398548]  kasan_slab_alloc+0x12/0x20
[   42.398848]  __kmalloc_node_track_caller+0xcb/0x380
[   42.399224]  __kmalloc_reserve.isra.32+0x41/0xe0
[   42.399654]  __alloc_skb+0xf8/0x580
[   42.400003]  sock_wmalloc+0xab/0xf0
[   42.400346]  __ip6_append_data.isra.41+0x2472/0x33d0
[   42.400813]  ip6_append_data+0x1a8/0x2f0
[   42.401122]  rawv6_sendmsg+0x11ee/0x2db0
[   42.401505]  inet_sendmsg+0x123/0x500
[   42.401860]  sock_sendmsg+0xca/0x110
[   42.402209]  ___sys_sendmsg+0x7cb/0x930
[   42.402582]  __sys_sendmsg+0xd9/0x190
[   42.402941]  SyS_sendmsg+0x2d/0x50
[   42.403273]  entry_SYSCALL_64_fastpath+0x1f/0xbe
[   42.403718]
[   42.403871] Freed by task 1794:
[   42.404146]  save_stack_trace+0x16/0x20
[   42.404515]  save_stack+0x46/0xd0
[   42.404827]  kasan_slab_free+0x72/0xc0
[   42.405167]  kfree+0xe8/0x2b0
[   42.405462]  skb_free_head+0x74/0xb0
[   42.405806]  skb_release_data+0x30e/0x3a0
[   42.406198]  skb_release_all+0x4a/0x60
[   42.406563]  consume_skb+0x113/0x2e0
[   42.406910]  skb_free_datagram+0x1a/0xe0
[   42.407288]  netlink_recvmsg+0x60d/0xe40
[   42.407667]  sock_recvmsg+0xd7/0x110
[   42.408022]  ___sys_recvmsg+0x25c/0x580
[   42.408395]  __sys_recvmsg+0xd6/0x190
[   42.408753]  SyS_recvmsg+0x2d/0x50
[   42.409086]  entry_SYSCALL_64_fastpath+0x1f/0xbe
[   42.409513]
[   42.409665] The buggy address belongs to the object at ffff88000969e780
[   42.409665]  which belongs to the cache kmalloc-512 of size 512
[   42.410846] The buggy address is located 24 bytes inside of
[   42.410846]  512-byte region [ffff88000969e780, ffff88000969e980)
[   42.411941] The buggy address belongs to the page:
[   42.412405] page:ffffea000025a780 count:1 mapcount:0 mapping:          (null) index:0x0 compound_mapcount: 0
[   42.413298] flags: 0x100000000008100(slab|head)
[   42.413729] raw: 0100000000008100 0000000000000000 0000000000000000 00000001800c000c
[   42.414387] raw: ffffea00002a9500 0000000900000007 ffff88000c401280 0000000000000000
[   42.415074] page dumped because: kasan: bad access detected
[   42.415604]
[   42.415757] Memory state around the buggy address:
[   42.416222]  ffff88000969e880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   42.416904]  ffff88000969e900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   42.417591] >ffff88000969e980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   42.418273]                    ^
[   42.418588]  ffff88000969ea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   42.419273]  ffff88000969ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   42.419882] ==================================================================

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Craig Gallek <kraig@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/tunnel: set inner protocol in network gro hooks 2017-03-09T21:19:52+00:00 Paolo Abeni pabeni@redhat.com 2017-03-07T17:33:31+00:00 294acf1c01bace5cea5d30b510504238bf5f7c25 The gso code of several tunnels type (gre and udp tunnels) takes for granted that the skb->inner_protocol is properly initialized and drops the packet elsewhere. On the forwarding path no one is initializing such field, so gro encapsulated packets are dropped on forward. Since commit 38720352412a ("gre: Use inner_proto to obtain inner header protocol"), this can be reproduced when the encapsulated packets use gre as the tunneling protocol. The issue happens also with vxlan and geneve tunnels since commit 8bce6d7d0d1e ("udp: Generalize skb_udp_segment"), if the forwarding host's ingress nic has h/w offload for such tunnel and a vxlan/geneve device is configured on top of it, regardless of the configured peer address and vni. To address the issue, this change initialize the inner_protocol field for encapsulated packets in both ipv4 and ipv6 gro complete callbacks. Fixes: 38720352412a ("gre: Use inner_proto to obtain inner header protocol") Fixes: 8bce6d7d0d1e ("udp: Generalize skb_udp_segment") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
The gso code of several tunnels type (gre and udp tunnels)
takes for granted that the skb->inner_protocol is properly
initialized and drops the packet elsewhere.

On the forwarding path no one is initializing such field,
so gro encapsulated packets are dropped on forward.

Since commit 38720352412a ("gre: Use inner_proto to obtain
inner header protocol"), this can be reproduced when the
encapsulated packets use gre as the tunneling protocol.

The issue happens also with vxlan and geneve tunnels since
commit 8bce6d7d0d1e ("udp: Generalize skb_udp_segment"), if the
forwarding host's ingress nic has h/w offload for such tunnel
and a vxlan/geneve device is configured on top of it, regardless
of the configured peer address and vni.

To address the issue, this change initialize the inner_protocol
field for encapsulated packets in both ipv4 and ipv6 gro complete
callbacks.

Fixes: 38720352412a ("gre: Use inner_proto to obtain inner header protocol")
Fixes: 8bce6d7d0d1e ("udp: Generalize skb_udp_segment")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: Add a skb_gro_flush_final helper. 2017-02-15T08:39:39+00:00 Steffen Klassert steffen.klassert@secunet.com 2017-02-15T08:39:39+00:00 5f114163f2f5eb2edbb49c4d3e0b405c7a8a7e2a Add a skb_gro_flush_final helper to prepare for consuming skbs in call_gro_receive. We will extend this helper to not touch the skb if the skb is consumed by a gro callback with a followup patch. We need this to handle the upcomming IPsec ESP callbacks as they reinject the skb to the napi_gro_receive asynchronous. The handler is used in all gro_receive functions that can call the ESP gro handlers. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> 
Add a skb_gro_flush_final helper to prepare for  consuming
skbs in call_gro_receive. We will extend this helper to not
touch the skb if the skb is consumed by a gro callback with
a followup patch. We need this to handle the upcomming IPsec
ESP callbacks as they reinject the skb to the napi_gro_receive
asynchronous. The handler is used in all gro_receive functions
that can call the ESP gro handlers.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
gro: Disable frag0 optimization on IPv6 ext headers 2017-01-11T02:30:33+00:00 Herbert Xu herbert@gondor.apana.org.au 2017-01-10T20:24:15+00:00 57ea52a865144aedbcd619ee0081155e658b6f7d The GRO fast path caches the frag0 address. This address becomes invalid if frag0 is modified by pskb_may_pull or its variants. So whenever that happens we must disable the frag0 optimization. This is usually done through the combination of gro_header_hard and gro_header_slow, however, the IPv6 extension header path did the pulling directly and would continue to use the GRO fast path incorrectly. This patch fixes it by disabling the fast path when we enter the IPv6 extension header path. Fixes: 78a478d0efd9 ("gro: Inline skb_gro_header and cache frag0 virtual address") Reported-by: Slava Shwartsman <slavash@mellanox.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
The GRO fast path caches the frag0 address.  This address becomes
invalid if frag0 is modified by pskb_may_pull or its variants.
So whenever that happens we must disable the frag0 optimization.

This is usually done through the combination of gro_header_hard
and gro_header_slow, however, the IPv6 extension header path did
the pulling directly and would continue to use the GRO fast path
incorrectly.

This patch fixes it by disabling the fast path when we enter the
IPv6 extension header path.

Fixes: 78a478d0efd9 ("gro: Inline skb_gro_header and cache frag0 virtual address")
Reported-by: Slava Shwartsman <slavash@mellanox.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>