linux_dsm_epyc7002/net/ipv6
Wei Wang a688caa34b ipv6: take rcu lock in rawv6_send_hdrinc()
In rawv6_send_hdrinc(), in order to avoid an extra dst_hold(), we
directly assign the dst to skb and set passed in dst to NULL to avoid
double free.
However, in error case, we free skb and then do stats update with the
dst pointer passed in. This causes use-after-free on the dst.
Fix it by taking rcu read lock right before dst could get released to
make sure dst does not get freed until the stats update is done.
Note: we don't have this issue in ipv4 cause dst is not used for stats
update in v4.

Syzkaller reported following crash:
BUG: KASAN: use-after-free in rawv6_send_hdrinc net/ipv6/raw.c:692 [inline]
BUG: KASAN: use-after-free in rawv6_sendmsg+0x4421/0x4630 net/ipv6/raw.c:921
Read of size 8 at addr ffff8801d95ba730 by task syz-executor0/32088

CPU: 1 PID: 32088 Comm: syz-executor0 Not tainted 4.19.0-rc2+ #93
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+0x1c4/0x2b4 lib/dump_stack.c:113
 print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 rawv6_send_hdrinc net/ipv6/raw.c:692 [inline]
 rawv6_sendmsg+0x4421/0x4630 net/ipv6/raw.c:921
 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:631
 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2114
 __sys_sendmsg+0x11d/0x280 net/socket.c:2152
 __do_sys_sendmsg net/socket.c:2161 [inline]
 __se_sys_sendmsg net/socket.c:2159 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457099
Code: fd b4 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 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f83756edc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f83756ee6d4 RCX: 0000000000457099
RDX: 0000000000000000 RSI: 0000000020003840 RDI: 0000000000000004
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d4b30 R14: 00000000004c90b1 R15: 0000000000000000

Allocated by task 32088:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490
 kmem_cache_alloc+0x12e/0x730 mm/slab.c:3554
 dst_alloc+0xbb/0x1d0 net/core/dst.c:105
 ip6_dst_alloc+0x35/0xa0 net/ipv6/route.c:353
 ip6_rt_cache_alloc+0x247/0x7b0 net/ipv6/route.c:1186
 ip6_pol_route+0x8f8/0xd90 net/ipv6/route.c:1895
 ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2093
 fib6_rule_lookup+0x277/0x860 net/ipv6/fib6_rules.c:122
 ip6_route_output_flags+0x2c5/0x350 net/ipv6/route.c:2121
 ip6_route_output include/net/ip6_route.h:88 [inline]
 ip6_dst_lookup_tail+0xe27/0x1d60 net/ipv6/ip6_output.c:951
 ip6_dst_lookup_flow+0xc8/0x270 net/ipv6/ip6_output.c:1079
 rawv6_sendmsg+0x12d9/0x4630 net/ipv6/raw.c:905
 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:631
 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2114
 __sys_sendmsg+0x11d/0x280 net/socket.c:2152
 __do_sys_sendmsg net/socket.c:2161 [inline]
 __se_sys_sendmsg net/socket.c:2159 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 5356:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kmem_cache_free+0x83/0x290 mm/slab.c:3756
 dst_destroy+0x267/0x3c0 net/core/dst.c:141
 dst_destroy_rcu+0x16/0x19 net/core/dst.c:154
 __rcu_reclaim kernel/rcu/rcu.h:236 [inline]
 rcu_do_batch kernel/rcu/tree.c:2576 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2880 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2847 [inline]
 rcu_process_callbacks+0xf23/0x2670 kernel/rcu/tree.c:2864
 __do_softirq+0x30b/0xad8 kernel/softirq.c:292

Fixes: 1789a640f5 ("raw: avoid two atomics in xmit")
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-05 14:45:34 -07:00
..
ila ila: remove blank lines at EOF 2018-07-24 14:10:42 -07:00
netfilter ip: frags: fix crash in ip_do_fragment() 2018-09-09 14:50:56 -07:00
addrconf_core.c net/ipv6: Add helper to return path MTU based on fib result 2018-05-22 10:51:09 +02:00
addrconf.c net/ipv6: Display all addresses in output of /proc/net/if_inet6 2018-09-21 19:10:49 -07:00
addrlabel.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
af_inet6.c ipv6: fix cleanup ordering for pingv6 registration 2018-08-29 19:28:55 -07:00
ah6.c
anycast.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
calipso.c ipv6: make ipv6_renew_options() interrupt/kernel safe 2018-07-05 20:15:26 +09:00
datagram.c net: add helpers checking if socket can be bound to nonlocal address 2018-08-01 09:50:04 -07:00
esp6_offload.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2018-07-27 09:33:37 -07:00
esp6.c esp6: fix memleak on error path in esp6_input 2018-06-27 17:32:11 +02:00
exthdrs_core.c net: ipv6: Fix typo in ipv6_find_hdr() documentation 2018-05-07 23:50:27 -04:00
exthdrs_offload.c
exthdrs.c ipv6: make ipv6_renew_options() interrupt/kernel safe 2018-07-05 20:15:26 +09:00
fib6_notifier.c
fib6_rules.c net/ipv6: Add fib6_lookup 2018-05-11 00:10:56 +02:00
fou6.c
icmp.c ipv6: Add icmp_echo_ignore_all support for ICMPv6 2018-08-13 08:42:25 -07:00
inet6_connection_sock.c
inet6_hashtables.c bpf: Enable BPF_PROG_TYPE_SK_REUSEPORT bpf prog in reuseport selection 2018-08-11 01:58:46 +02:00
ip6_checksum.c udplite: fix partial checksum initialization 2018-02-16 15:57:42 -05:00
ip6_fib.c net/ipv6: Only update MTU metric if it set 2018-09-02 14:03:54 -07:00
ip6_flowlabel.c ipv6: fold sockcm_cookie into ipcm6_cookie 2018-07-07 10:58:49 +09:00
ip6_gre.c erspan: set erspan_ver to 1 by default when adding an erspan dev 2018-08-27 15:13:17 -07:00
ip6_icmp.c
ip6_input.c net: ipv6: listify ipv6_rcv() and ip6_rcv_finish() 2018-07-06 11:19:07 +09:00
ip6_offload.c gso_segment: Reset skb->mac_len after modifying network header 2018-09-13 12:09:32 -07:00
ip6_offload.h
ip6_output.c ipv6: fix possible use-after-free in ip6_xmit() 2018-09-17 07:56:02 -07:00
ip6_tunnel.c ip6_tunnel: be careful when accessing the inner header 2018-09-19 21:24:28 -07:00
ip6_udp_tunnel.c
ip6_vti.c vti6: remove !skb->ignore_df check from vti6_xmit() 2018-08-29 17:51:44 -07:00
ip6mr.c rhashtable: split rhashtable.h 2018-06-22 13:43:27 +09:00
ipcomp6.c
ipv6_sockglue.c Merge ra.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux 2018-07-20 21:17:12 -07:00
Kconfig net: remove blank lines at end of file 2018-07-24 14:10:43 -07:00
Makefile
mcast_snoop.c
mcast.c Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net 2018-07-24 19:21:58 -07:00
mip6.c
ndisc.c ipv6: make DAD fail with enhanced DAD when nonce length differs 2018-07-16 13:45:16 -07:00
netfilter.c netfilter: utils: move nf_ip6_checksum* from ipv6 to utils 2018-07-16 17:51:48 +02:00
output_core.c
ping.c ipv6: fold sockcm_cookie into ipcm6_cookie 2018-07-07 10:58:49 +09:00
proc.c proc: introduce proc_create_net_single 2018-05-16 07:24:30 +02:00
protocol.c
raw.c ipv6: take rcu lock in rawv6_send_hdrinc() 2018-10-05 14:45:34 -07:00
reassembly.c ipv6: defrag: drop non-last frags smaller than min mtu 2018-08-05 17:21:14 -07:00
route.c net/ipv6: Remove extra call to ip6_convert_metrics for multipath case 2018-09-26 19:57:23 -07:00
seg6_hmac.c Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net 2018-07-03 10:29:26 +09:00
seg6_iptunnel.c ipv6: sr: fix useless rol32 call on hash 2018-07-18 15:10:47 -07:00
seg6_local.c bpf: add End.DT6 action to bpf_lwt_seg6_action helper 2018-07-31 09:22:48 +02:00
seg6.c rhashtable: split rhashtable.h 2018-06-22 13:43:27 +09:00
sit.c ip6_tunnel: remove magic mtu value 0xFFF8 2018-06-01 13:56:30 -04:00
syncookies.c net/ipv4: disable SMC TCP option with SYN Cookies 2018-03-25 20:53:54 -04:00
sysctl_net_ipv6.c ipv6: sr: Compute flowlabel for outer IPv6 header of seg6 encap mode 2018-04-25 13:02:15 -04:00
tcp_ipv6.c net/ipv6: Fix linklocal to global address with VRF 2018-07-21 19:31:46 -07:00
tcpv6_offload.c net: Convert GRO SKB handling to list_head. 2018-06-26 11:33:04 +09:00
tunnel6.c
udp_impl.h
udp_offload.c net: Convert GRO SKB handling to list_head. 2018-06-26 11:33:04 +09:00
udp.c udp6: add missing checks on edumux packet processing 2018-09-16 15:27:44 -07:00
udplite.c proc: introduce proc_create_net{,_data} 2018-05-16 07:24:30 +02:00
xfrm6_input.c xfrm: reset transport header back to network header after all input transforms ahave been applied 2018-09-04 10:26:30 +02:00
xfrm6_mode_beet.c
xfrm6_mode_ro.c ipv6: xfrm: use 64-bit timestamps 2018-07-11 15:26:35 +02:00
xfrm6_mode_transport.c xfrm: reset transport header back to network header after all input transforms ahave been applied 2018-09-04 10:26:30 +02:00
xfrm6_mode_tunnel.c xfrm: Verify MAC header exists before overwriting eth_hdr(skb)->h_proto 2018-03-07 10:54:29 +01:00
xfrm6_output.c xfrm6: call kfree_skb when skb is toobig 2018-09-03 07:37:57 +02:00
xfrm6_policy.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-06-03 09:31:58 -04:00
xfrm6_protocol.c
xfrm6_state.c xfrm: remove VLA usage in __xfrm6_sort() 2018-04-26 07:51:48 +02:00
xfrm6_tunnel.c xfrm: Fix warning in xfrm6_tunnel_net_exit. 2018-04-16 07:50:09 +02:00