linux-stable.git/net/ipv4, branch v4.19.48 Linux kernel stable tree ipv4/igmp: fix build error if !CONFIG_IP_MULTICAST 2019-06-04T06:02:31+00:00 Eric Dumazet edumazet@google.com 2019-05-23T01:35:16+00:00 46702dd5d504d99546b8f1c0ff4c67de78f959e1 [ Upstream commit 903869bd10e6719b9df6718e785be7ec725df59f ] ip_sf_list_clear_all() needs to be defined even if !CONFIG_IP_MULTICAST Fixes: 3580d04aa674 ("ipv4/igmp: fix another memory leak in igmpv3_del_delrec()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 903869bd10e6719b9df6718e785be7ec725df59f ]

ip_sf_list_clear_all() needs to be defined even if !CONFIG_IP_MULTICAST

Fixes: 3580d04aa674 ("ipv4/igmp: fix another memory leak in igmpv3_del_delrec()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipv4/igmp: fix another memory leak in igmpv3_del_delrec() 2019-06-04T06:02:31+00:00 Eric Dumazet edumazet@google.com 2019-05-22T23:51:22+00:00 e9f94e480f3ed951f3fb6693b3b0b19811e67f66 [ Upstream commit 3580d04aa674383c42de7b635d28e52a1e5bc72c ] syzbot reported memory leaks [1] that I have back tracked to a missing cleanup from igmpv3_del_delrec() when (im->sfmode != MCAST_INCLUDE) Add ip_sf_list_clear_all() and kfree_pmc() helpers to explicitely handle the cleanups before freeing. [1] BUG: memory leak unreferenced object 0xffff888123e32b00 (size 64): comm "softirq", pid 0, jiffies 4294942968 (age 8.010s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 e0 00 00 01 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<000000006105011b>] kmemleak_alloc_recursive include/linux/kmemleak.h:55 [inline] [<000000006105011b>] slab_post_alloc_hook mm/slab.h:439 [inline] [<000000006105011b>] slab_alloc mm/slab.c:3326 [inline] [<000000006105011b>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553 [<000000004bba8073>] kmalloc include/linux/slab.h:547 [inline] [<000000004bba8073>] kzalloc include/linux/slab.h:742 [inline] [<000000004bba8073>] ip_mc_add1_src net/ipv4/igmp.c:1961 [inline] [<000000004bba8073>] ip_mc_add_src+0x36b/0x400 net/ipv4/igmp.c:2085 [<00000000a46a65a0>] ip_mc_msfilter+0x22d/0x310 net/ipv4/igmp.c:2475 [<000000005956ca89>] do_ip_setsockopt.isra.0+0x1795/0x1930 net/ipv4/ip_sockglue.c:957 [<00000000848e2d2f>] ip_setsockopt+0x3b/0xb0 net/ipv4/ip_sockglue.c:1246 [<00000000b9db185c>] udp_setsockopt+0x4e/0x90 net/ipv4/udp.c:2616 [<000000003028e438>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3130 [<0000000015b65589>] __sys_setsockopt+0x98/0x120 net/socket.c:2078 [<00000000ac198ef0>] __do_sys_setsockopt net/socket.c:2089 [inline] [<00000000ac198ef0>] __se_sys_setsockopt net/socket.c:2086 [inline] [<00000000ac198ef0>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2086 [<000000000a770437>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:301 [<00000000d3adb93b>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 9c8bb163ae78 ("igmp, mld: Fix memory leak in igmpv3/mld_del_delrec()") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Hangbin Liu <liuhangbin@gmail.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 3580d04aa674383c42de7b635d28e52a1e5bc72c ]

syzbot reported memory leaks [1] that I have back tracked to
a missing cleanup from igmpv3_del_delrec() when
(im->sfmode != MCAST_INCLUDE)

Add ip_sf_list_clear_all() and kfree_pmc() helpers to explicitely
handle the cleanups before freeing.

[1]

BUG: memory leak
unreferenced object 0xffff888123e32b00 (size 64):
  comm "softirq", pid 0, jiffies 4294942968 (age 8.010s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 e0 00 00 01 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<000000006105011b>] kmemleak_alloc_recursive include/linux/kmemleak.h:55 [inline]
    [<000000006105011b>] slab_post_alloc_hook mm/slab.h:439 [inline]
    [<000000006105011b>] slab_alloc mm/slab.c:3326 [inline]
    [<000000006105011b>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553
    [<000000004bba8073>] kmalloc include/linux/slab.h:547 [inline]
    [<000000004bba8073>] kzalloc include/linux/slab.h:742 [inline]
    [<000000004bba8073>] ip_mc_add1_src net/ipv4/igmp.c:1961 [inline]
    [<000000004bba8073>] ip_mc_add_src+0x36b/0x400 net/ipv4/igmp.c:2085
    [<00000000a46a65a0>] ip_mc_msfilter+0x22d/0x310 net/ipv4/igmp.c:2475
    [<000000005956ca89>] do_ip_setsockopt.isra.0+0x1795/0x1930 net/ipv4/ip_sockglue.c:957
    [<00000000848e2d2f>] ip_setsockopt+0x3b/0xb0 net/ipv4/ip_sockglue.c:1246
    [<00000000b9db185c>] udp_setsockopt+0x4e/0x90 net/ipv4/udp.c:2616
    [<000000003028e438>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3130
    [<0000000015b65589>] __sys_setsockopt+0x98/0x120 net/socket.c:2078
    [<00000000ac198ef0>] __do_sys_setsockopt net/socket.c:2089 [inline]
    [<00000000ac198ef0>] __se_sys_setsockopt net/socket.c:2086 [inline]
    [<00000000ac198ef0>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2086
    [<000000000a770437>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:301
    [<00000000d3adb93b>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 9c8bb163ae78 ("igmp, mld: Fix memory leak in igmpv3/mld_del_delrec()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Hangbin Liu <liuhangbin@gmail.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
inet: switch IP ID generator to siphash 2019-06-04T06:02:30+00:00 Eric Dumazet edumazet@google.com 2019-03-27T19:40:33+00:00 07480da0c8a1979e0973d6dd783b6aed966dccf6 [ Upstream commit df453700e8d81b1bdafdf684365ee2b9431fb702 ] According to Amit Klein and Benny Pinkas, IP ID generation is too weak and might be used by attackers. Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix()) having 64bit key and Jenkins hash is risky. It is time to switch to siphash and its 128bit keys. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit df453700e8d81b1bdafdf684365ee2b9431fb702 ]

According to Amit Klein and Benny Pinkas, IP ID generation is too weak
and might be used by attackers.

Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix())
having 64bit key and Jenkins hash is risky.

It is time to switch to siphash and its 128bit keys.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Amit Klein <aksecurity@gmail.com>
Reported-by: Benny Pinkas <benny@pinkas.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xfrm4: Fix uninitialized memory read in _decode_session4 2019-05-25T16:23:41+00:00 Steffen Klassert steffen.klassert@secunet.com 2019-02-26T06:04:50+00:00 a654a73de29fe95b463fdbf792c681b67fb31780 [ Upstream commit 8742dc86d0c7a9628117a989c11f04a9b6b898f3 ] We currently don't reload pointers pointing into skb header after doing pskb_may_pull() in _decode_session4(). So in case pskb_may_pull() changed the pointers, we read from random memory. Fix this by putting all the needed infos on the stack, so that we don't need to access the header pointers after doing pskb_may_pull(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 8742dc86d0c7a9628117a989c11f04a9b6b898f3 ]

We currently don't reload pointers pointing into skb header
after doing pskb_may_pull() in _decode_session4(). So in case
pskb_may_pull() changed the pointers, we read from random
memory. Fix this by putting all the needed infos on the
stack, so that we don't need to access the header pointers
after doing pskb_may_pull().

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
esp4: add length check for UDP encapsulation 2019-05-25T16:23:41+00:00 Sabrina Dubroca sd@queasysnail.net 2019-03-25T13:30:00+00:00 3716c26250997e5c78146c873094360a6d644df5 [ Upstream commit 8dfb4eba4100e7cdd161a8baef2d8d61b7a7e62e ] esp_output_udp_encap can produce a length that doesn't fit in the 16 bits of a UDP header's length field. In that case, we'll send a fragmented packet whose length is larger than IP_MAX_MTU (resulting in "Oversized IP packet" warnings on receive) and with a bogus UDP length. To prevent this, add a length check to esp_output_udp_encap and return -EMSGSIZE on failure. This seems to be older than git history. Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 8dfb4eba4100e7cdd161a8baef2d8d61b7a7e62e ]

esp_output_udp_encap can produce a length that doesn't fit in the 16
bits of a UDP header's length field. In that case, we'll send a
fragmented packet whose length is larger than IP_MAX_MTU (resulting in
"Oversized IP packet" warnings on receive) and with a bogus UDP
length.

To prevent this, add a length check to esp_output_udp_encap and return
 -EMSGSIZE on failure.

This seems to be older than git history.

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
vti4: ipip tunnel deregistration fixes. 2019-05-25T16:23:41+00:00 Jeremy Sowden jeremy@azazel.net 2019-03-19T15:39:20+00:00 159269cc645637fbb39400f246c39f30651c4cd0 [ Upstream commit 5483844c3fc18474de29f5d6733003526e0a9f78 ] If tunnel registration failed during module initialization, the module would fail to deregister the IPPROTO_COMP protocol and would attempt to deregister the tunnel. The tunnel was not deregistered during module-exit. Fixes: dd9ee3444014e ("vti4: Fix a ipip packet processing bug in 'IPCOMP' virtual tunnel") Signed-off-by: Jeremy Sowden <jeremy@azazel.net> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 5483844c3fc18474de29f5d6733003526e0a9f78 ]

If tunnel registration failed during module initialization, the module
would fail to deregister the IPPROTO_COMP protocol and would attempt to
deregister the tunnel.

The tunnel was not deregistered during module-exit.

Fixes: dd9ee3444014e ("vti4: Fix a ipip packet processing bug in 'IPCOMP' virtual tunnel")
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ipv4: Fix raw socket lookup for local traffic 2019-05-16T17:41:29+00:00 David Ahern dsahern@gmail.com 2019-05-08T03:44:59+00:00 da2e770f0c4adb6fd58663e94fa1e4a57b0ad8dc [ Upstream commit 19e4e768064a87b073a4b4c138b55db70e0cfb9f ] inet_iif should be used for the raw socket lookup. inet_iif considers rt_iif which handles the case of local traffic. As it stands, ping to a local address with the '-I <dev>' option fails ever since ping was changed to use SO_BINDTODEVICE instead of cmsg + IP_PKTINFO. IPv6 works fine. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 19e4e768064a87b073a4b4c138b55db70e0cfb9f ]

inet_iif should be used for the raw socket lookup. inet_iif considers
rt_iif which handles the case of local traffic.

As it stands, ping to a local address with the '-I <dev>' option fails
ever since ping was changed to use SO_BINDTODEVICE instead of
cmsg + IP_PKTINFO.

IPv6 works fine.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipv4: ip_do_fragment: Preserve skb_iif during fragmentation 2019-05-05T12:42:36+00:00 Shmulik Ladkani shmulik@metanetworks.com 2019-04-29T13:39:30+00:00 3f611a479962ed4ab3682cbb0deb476f90d513f5 [ Upstream commit d2f0c961148f65bc73eda72b9fa3a4e80973cb49 ] Previously, during fragmentation after forwarding, skb->skb_iif isn't preserved, i.e. 'ip_copy_metadata' does not copy skb_iif from given 'from' skb. As a result, ip_do_fragment's creates fragments with zero skb_iif, leading to inconsistent behavior. Assume for example an eBPF program attached at tc egress (post forwarding) that examines __sk_buff->ingress_ifindex: - the correct iif is observed if forwarding path does not involve fragmentation/refragmentation - a bogus iif is observed if forwarding path involves fragmentation/refragmentatiom Fix, by preserving skb_iif during 'ip_copy_metadata'. Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit d2f0c961148f65bc73eda72b9fa3a4e80973cb49 ]

Previously, during fragmentation after forwarding, skb->skb_iif isn't
preserved, i.e. 'ip_copy_metadata' does not copy skb_iif from given
'from' skb.

As a result, ip_do_fragment's creates fragments with zero skb_iif,
leading to inconsistent behavior.

Assume for example an eBPF program attached at tc egress (post
forwarding) that examines __sk_buff->ingress_ifindex:
 - the correct iif is observed if forwarding path does not involve
   fragmentation/refragmentation
 - a bogus iif is observed if forwarding path involves
   fragmentation/refragmentatiom

Fix, by preserving skb_iif during 'ip_copy_metadata'.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipv4: set the tcp_min_rtt_wlen range from 0 to one day 2019-05-02T07:58:59+00:00 ZhangXiaoxu zhangxiaoxu5@huawei.com 2019-04-16T01:47:24+00:00 250e51f856e1534e3e769add508f121966030462 [ Upstream commit 19fad20d15a6494f47f85d869f00b11343ee5c78 ] There is a UBSAN report as below: UBSAN: Undefined behaviour in net/ipv4/tcp_input.c:2877:56 signed integer overflow: 2147483647 * 1000 cannot be represented in type 'int' CPU: 3 PID: 0 Comm: swapper/3 Not tainted 5.1.0-rc4-00058-g582549e #1 Call Trace: <IRQ> dump_stack+0x8c/0xba ubsan_epilogue+0x11/0x60 handle_overflow+0x12d/0x170 ? ttwu_do_wakeup+0x21/0x320 __ubsan_handle_mul_overflow+0x12/0x20 tcp_ack_update_rtt+0x76c/0x780 tcp_clean_rtx_queue+0x499/0x14d0 tcp_ack+0x69e/0x1240 ? __wake_up_sync_key+0x2c/0x50 ? update_group_capacity+0x50/0x680 tcp_rcv_established+0x4e2/0xe10 tcp_v4_do_rcv+0x22b/0x420 tcp_v4_rcv+0xfe8/0x1190 ip_protocol_deliver_rcu+0x36/0x180 ip_local_deliver+0x15b/0x1a0 ip_rcv+0xac/0xd0 __netif_receive_skb_one_core+0x7f/0xb0 __netif_receive_skb+0x33/0xc0 netif_receive_skb_internal+0x84/0x1c0 napi_gro_receive+0x2a0/0x300 receive_buf+0x3d4/0x2350 ? detach_buf_split+0x159/0x390 virtnet_poll+0x198/0x840 ? reweight_entity+0x243/0x4b0 net_rx_action+0x25c/0x770 __do_softirq+0x19b/0x66d irq_exit+0x1eb/0x230 do_IRQ+0x7a/0x150 common_interrupt+0xf/0xf </IRQ> It can be reproduced by: echo 2147483647 > /proc/sys/net/ipv4/tcp_min_rtt_wlen Fixes: f672258391b42 ("tcp: track min RTT using windowed min-filter") Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 19fad20d15a6494f47f85d869f00b11343ee5c78 ]

There is a UBSAN report as below:
UBSAN: Undefined behaviour in net/ipv4/tcp_input.c:2877:56
signed integer overflow:
2147483647 * 1000 cannot be represented in type 'int'
CPU: 3 PID: 0 Comm: swapper/3 Not tainted 5.1.0-rc4-00058-g582549e #1
Call Trace:
 <IRQ>
 dump_stack+0x8c/0xba
 ubsan_epilogue+0x11/0x60
 handle_overflow+0x12d/0x170
 ? ttwu_do_wakeup+0x21/0x320
 __ubsan_handle_mul_overflow+0x12/0x20
 tcp_ack_update_rtt+0x76c/0x780
 tcp_clean_rtx_queue+0x499/0x14d0
 tcp_ack+0x69e/0x1240
 ? __wake_up_sync_key+0x2c/0x50
 ? update_group_capacity+0x50/0x680
 tcp_rcv_established+0x4e2/0xe10
 tcp_v4_do_rcv+0x22b/0x420
 tcp_v4_rcv+0xfe8/0x1190
 ip_protocol_deliver_rcu+0x36/0x180
 ip_local_deliver+0x15b/0x1a0
 ip_rcv+0xac/0xd0
 __netif_receive_skb_one_core+0x7f/0xb0
 __netif_receive_skb+0x33/0xc0
 netif_receive_skb_internal+0x84/0x1c0
 napi_gro_receive+0x2a0/0x300
 receive_buf+0x3d4/0x2350
 ? detach_buf_split+0x159/0x390
 virtnet_poll+0x198/0x840
 ? reweight_entity+0x243/0x4b0
 net_rx_action+0x25c/0x770
 __do_softirq+0x19b/0x66d
 irq_exit+0x1eb/0x230
 do_IRQ+0x7a/0x150
 common_interrupt+0xf/0xf
 </IRQ>

It can be reproduced by:
  echo 2147483647 > /proc/sys/net/ipv4/tcp_min_rtt_wlen

Fixes: f672258391b42 ("tcp: track min RTT using windowed min-filter")
Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipv4: add sanity checks in ipv4_link_failure() 2019-05-02T07:58:59+00:00 Eric Dumazet edumazet@google.com 2019-04-24T15:04:05+00:00 07445fea95754b79814fb65259d71bf0ef0c3be7 [ Upstream commit 20ff83f10f113c88d0bb74589389b05250994c16 ] Before calling __ip_options_compile(), we need to ensure the network header is a an IPv4 one, and that it is already pulled in skb->head. RAW sockets going through a tunnel can end up calling ipv4_link_failure() with total garbage in the skb, or arbitrary lengthes. syzbot report : BUG: KASAN: stack-out-of-bounds in memcpy include/linux/string.h:355 [inline] BUG: KASAN: stack-out-of-bounds in __ip_options_echo+0x294/0x1120 net/ipv4/ip_options.c:123 Write of size 69 at addr ffff888096abf068 by task syz-executor.4/9204 CPU: 0 PID: 9204 Comm: syz-executor.4 Not tainted 5.1.0-rc5+ #77 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 memcpy+0x38/0x50 mm/kasan/common.c:133 memcpy include/linux/string.h:355 [inline] __ip_options_echo+0x294/0x1120 net/ipv4/ip_options.c:123 __icmp_send+0x725/0x1400 net/ipv4/icmp.c:695 ipv4_link_failure+0x29f/0x550 net/ipv4/route.c:1204 dst_link_failure include/net/dst.h:427 [inline] vti6_xmit net/ipv6/ip6_vti.c:514 [inline] vti6_tnl_xmit+0x10d4/0x1c0c net/ipv6/ip6_vti.c:553 __netdev_start_xmit include/linux/netdevice.h:4414 [inline] netdev_start_xmit include/linux/netdevice.h:4423 [inline] xmit_one net/core/dev.c:3292 [inline] dev_hard_start_xmit+0x1b2/0x980 net/core/dev.c:3308 __dev_queue_xmit+0x271d/0x3060 net/core/dev.c:3878 dev_queue_xmit+0x18/0x20 net/core/dev.c:3911 neigh_direct_output+0x16/0x20 net/core/neighbour.c:1527 neigh_output include/net/neighbour.h:508 [inline] ip_finish_output2+0x949/0x1740 net/ipv4/ip_output.c:229 ip_finish_output+0x73c/0xd50 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip_output+0x21f/0x670 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] raw_send_hdrinc net/ipv4/raw.c:432 [inline] raw_sendmsg+0x1d2b/0x2f20 net/ipv4/raw.c:663 inet_sendmsg+0x147/0x5d0 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:661 sock_write_iter+0x27c/0x3e0 net/socket.c:988 call_write_iter include/linux/fs.h:1866 [inline] new_sync_write+0x4c7/0x760 fs/read_write.c:474 __vfs_write+0xe4/0x110 fs/read_write.c:487 vfs_write+0x20c/0x580 fs/read_write.c:549 ksys_write+0x14f/0x2d0 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:608 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c29 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f293b44bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458c29 RDX: 0000000000000014 RSI: 00000000200002c0 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f293b44c6d4 R13: 00000000004c8623 R14: 00000000004ded68 R15: 00000000ffffffff The buggy address belongs to the page: page:ffffea00025aafc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x1fffc0000000000() raw: 01fffc0000000000 0000000000000000 ffffffff025a0101 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888096abef80: 00 00 00 f2 f2 f2 f2 f2 00 00 00 00 00 00 00 f2 ffff888096abf000: f2 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888096abf080: 00 00 f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 ^ ffff888096abf100: 00 00 00 00 f1 f1 f1 f1 00 00 f3 f3 00 00 00 00 ffff888096abf180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 Fixes: ed0de45a1008 ("ipv4: recompile ip options in ipv4_link_failure") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Stephen Suryaputra <ssuryaextr@gmail.com> Acked-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> 
[ Upstream commit 20ff83f10f113c88d0bb74589389b05250994c16 ]

Before calling __ip_options_compile(), we need to ensure the network
header is a an IPv4 one, and that it is already pulled in skb->head.

RAW sockets going through a tunnel can end up calling ipv4_link_failure()
with total garbage in the skb, or arbitrary lengthes.

syzbot report :

BUG: KASAN: stack-out-of-bounds in memcpy include/linux/string.h:355 [inline]
BUG: KASAN: stack-out-of-bounds in __ip_options_echo+0x294/0x1120 net/ipv4/ip_options.c:123
Write of size 69 at addr ffff888096abf068 by task syz-executor.4/9204

CPU: 0 PID: 9204 Comm: syz-executor.4 Not tainted 5.1.0-rc5+ #77
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x123/0x190 mm/kasan/generic.c:191
 memcpy+0x38/0x50 mm/kasan/common.c:133
 memcpy include/linux/string.h:355 [inline]
 __ip_options_echo+0x294/0x1120 net/ipv4/ip_options.c:123
 __icmp_send+0x725/0x1400 net/ipv4/icmp.c:695
 ipv4_link_failure+0x29f/0x550 net/ipv4/route.c:1204
 dst_link_failure include/net/dst.h:427 [inline]
 vti6_xmit net/ipv6/ip6_vti.c:514 [inline]
 vti6_tnl_xmit+0x10d4/0x1c0c net/ipv6/ip6_vti.c:553
 __netdev_start_xmit include/linux/netdevice.h:4414 [inline]
 netdev_start_xmit include/linux/netdevice.h:4423 [inline]
 xmit_one net/core/dev.c:3292 [inline]
 dev_hard_start_xmit+0x1b2/0x980 net/core/dev.c:3308
 __dev_queue_xmit+0x271d/0x3060 net/core/dev.c:3878
 dev_queue_xmit+0x18/0x20 net/core/dev.c:3911
 neigh_direct_output+0x16/0x20 net/core/neighbour.c:1527
 neigh_output include/net/neighbour.h:508 [inline]
 ip_finish_output2+0x949/0x1740 net/ipv4/ip_output.c:229
 ip_finish_output+0x73c/0xd50 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip_output+0x21f/0x670 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:444 [inline]
 NF_HOOK include/linux/netfilter.h:289 [inline]
 raw_send_hdrinc net/ipv4/raw.c:432 [inline]
 raw_sendmsg+0x1d2b/0x2f20 net/ipv4/raw.c:663
 inet_sendmsg+0x147/0x5d0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:661
 sock_write_iter+0x27c/0x3e0 net/socket.c:988
 call_write_iter include/linux/fs.h:1866 [inline]
 new_sync_write+0x4c7/0x760 fs/read_write.c:474
 __vfs_write+0xe4/0x110 fs/read_write.c:487
 vfs_write+0x20c/0x580 fs/read_write.c:549
 ksys_write+0x14f/0x2d0 fs/read_write.c:599
 __do_sys_write fs/read_write.c:611 [inline]
 __se_sys_write fs/read_write.c:608 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:608
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458c29
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f293b44bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458c29
RDX: 0000000000000014 RSI: 00000000200002c0 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f293b44c6d4
R13: 00000000004c8623 R14: 00000000004ded68 R15: 00000000ffffffff

The buggy address belongs to the page:
page:ffffea00025aafc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x1fffc0000000000()
raw: 01fffc0000000000 0000000000000000 ffffffff025a0101 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888096abef80: 00 00 00 f2 f2 f2 f2 f2 00 00 00 00 00 00 00 f2
 ffff888096abf000: f2 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888096abf080: 00 00 f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00
                         ^
 ffff888096abf100: 00 00 00 00 f1 f1 f1 f1 00 00 f3 f3 00 00 00 00
 ffff888096abf180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Fixes: ed0de45a1008 ("ipv4: recompile ip options in ipv4_link_failure")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Stephen Suryaputra <ssuryaextr@gmail.com>
Acked-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>