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KASAN: slab-out-of-bounds Read in ip6_dst_lookup_tail

Status: closed as invalid on 2019/05/15 22:57
Subsystems: net
[Documentation on labels]
First crash: 1881d, last: 1831d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-out-of-bounds Read in ip6_dst_lookup_tail (2) net 75 1743d 1769d 0/26 closed as invalid on 2019/07/23 00:27

Sample crash report:
==================================================================
BUG: KASAN: slab-out-of-bounds in rt6_nexthop include/net/ip6_route.h:267 [inline]
BUG: KASAN: slab-out-of-bounds in ip6_dst_lookup_tail+0x1882/0x1b30 net/ipv6/ip6_output.c:1009
Read of size 4 at addr ffff8880a46bbbaa by task syz-executor.0/21575

CPU: 1 PID: 21575 Comm: syz-executor.0 Not tainted 5.0.0+ #135
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __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
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131
 rt6_nexthop include/net/ip6_route.h:267 [inline]
 ip6_dst_lookup_tail+0x1882/0x1b30 net/ipv6/ip6_output.c:1009
 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1092
 sctp_v6_get_dst+0x785/0x1d80 net/sctp/ipv6.c:293
 sctp_transport_route+0x132/0x370 net/sctp/transport.c:312
 sctp_assoc_add_peer+0x53e/0xfc0 net/sctp/associola.c:678
 sctp_process_param net/sctp/sm_make_chunk.c:2548 [inline]
 sctp_process_init+0x249f/0x2b20 net/sctp/sm_make_chunk.c:2361
 sctp_sf_do_5_1B_init+0x8ba/0xe50 net/sctp/sm_statefuns.c:416
 sctp_do_sm+0x124/0x53e0 net/sctp/sm_sideeffect.c:1188
 sctp_endpoint_bh_rcv+0x451/0x950 net/sctp/endpointola.c:458
 sctp_inq_push+0x1ea/0x290 net/sctp/inqueue.c:95
 sctp_rcv+0x2818/0x3570 net/sctp/input.c:271
 sctp6_rcv+0x17/0x30 net/sctp/ipv6.c:1063
 ip6_protocol_deliver_rcu+0x303/0x16c0 net/ipv6/ip6_input.c:394
 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:434
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 ip6_input+0xe4/0x3f0 net/ipv6/ip6_input.c:443
 dst_input include/net/dst.h:450 [inline]
 ip6_rcv_finish+0x1e7/0x320 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 ipv6_rcv+0x10e/0x420 net/ipv6/ip6_input.c:272
 __netif_receive_skb_one_core+0x115/0x1a0 net/core/dev.c:4973
 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083
 process_backlog+0x206/0x750 net/core/dev.c:5923
 napi_poll net/core/dev.c:6346 [inline]
 net_rx_action+0x4fa/0x1070 net/core/dev.c:6412
 __do_softirq+0x266/0x95a kernel/softirq.c:293
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027
 </IRQ>
 do_softirq.part.0+0x11a/0x170 kernel/softirq.c:338
 do_softirq kernel/softirq.c:330 [inline]
 __local_bh_enable_ip+0x211/0x270 kernel/softirq.c:190
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:684 [inline]
 ip6_finish_output2+0xbcf/0x2550 net/ipv6/ip6_output.c:121
 ip6_finish_output+0x577/0xc30 net/ipv6/ip6_output.c:154
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip6_output+0x235/0x7f0 net/ipv6/ip6_output.c:171
 dst_output include/net/dst.h:444 [inline]
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 ip6_xmit+0xe41/0x20c0 net/ipv6/ip6_output.c:275
 sctp_v6_xmit+0x313/0x660 net/sctp/ipv6.c:232
 sctp_packet_transmit+0x1bc4/0x36f0 net/sctp/output.c:641
 sctp_packet_singleton net/sctp/outqueue.c:787 [inline]
 sctp_outq_flush_ctrl.constprop.0+0x6d4/0xd50 net/sctp/outqueue.c:918
 sctp_outq_flush+0xe8/0x2780 net/sctp/outqueue.c:1200
 sctp_outq_uncork+0x6c/0x80 net/sctp/outqueue.c:772
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1820 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1220 [inline]
 sctp_do_sm+0x559/0x53e0 net/sctp/sm_sideeffect.c:1191
 sctp_primitive_ASSOCIATE+0x9d/0xd0 net/sctp/primitive.c:88
 __sctp_connect+0x8cd/0xce0 net/sctp/socket.c:1226
 __sctp_setsockopt_connectx+0x133/0x1a0 net/sctp/socket.c:1349
 sctp_setsockopt_connectx_old net/sctp/socket.c:1365 [inline]
 sctp_setsockopt net/sctp/socket.c:4656 [inline]
 sctp_setsockopt+0x22cc/0x6d20 net/sctp/socket.c:4620
 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3120
 __sys_setsockopt+0x180/0x280 net/socket.c:2046
 __do_sys_setsockopt net/socket.c:2057 [inline]
 __se_sys_setsockopt net/socket.c:2054 [inline]
 __x64_sys_setsockopt+0xbe/0x150 net/socket.c:2054
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458209
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:00007f901ee5cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000458209
RDX: 000000000000006b RSI: 0000000000000084 RDI: 0000000000000005
RBP: 000000000073bf00 R08: 000000000000001c R09: 0000000000000000
R10: 000000002055bfe4 R11: 0000000000000246 R12: 00007f901ee5d6d4
R13: 00000000004ccd38 R14: 00000000004daae0 R15: 00000000ffffffff

Allocated by task 7807:
 save_stack+0x45/0xd0 mm/kasan/common.c:75
 set_track mm/kasan/common.c:87 [inline]
 __kasan_kmalloc mm/kasan/common.c:497 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470
 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:505
 slab_post_alloc_hook mm/slab.h:436 [inline]
 slab_alloc mm/slab.c:3392 [inline]
 kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3554
 dst_alloc+0x10e/0x200 net/core/dst.c:109
 ip6_dst_alloc+0x34/0xa0 net/ipv6/route.c:355
 ip6_rt_pcpu_alloc net/ipv6/route.c:1225 [inline]
 rt6_make_pcpu_route net/ipv6/route.c:1255 [inline]
 ip6_pol_route+0x743/0x1040 net/ipv6/route.c:1909
 ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2082
 fib6_rule_lookup+0x128/0x560 net/ipv6/fib6_rules.c:118
 ip6_route_output_flags+0x2c4/0x350 net/ipv6/route.c:2111
 ip6_route_output include/net/ip6_route.h:88 [inline]
 ip6_dst_lookup_tail+0xd10/0x1b30 net/ipv6/ip6_output.c:964
 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1092
 sctp_v6_get_dst+0x785/0x1d80 net/sctp/ipv6.c:293
 sctp_transport_route+0x132/0x370 net/sctp/transport.c:312
 sctp_assoc_add_peer+0x53e/0xfc0 net/sctp/associola.c:678
 sctp_process_param net/sctp/sm_make_chunk.c:2548 [inline]
 sctp_process_init+0x249f/0x2b20 net/sctp/sm_make_chunk.c:2361
 sctp_sf_do_5_1B_init+0x8ba/0xe50 net/sctp/sm_statefuns.c:416
 sctp_do_sm+0x124/0x53e0 net/sctp/sm_sideeffect.c:1188
 sctp_endpoint_bh_rcv+0x451/0x950 net/sctp/endpointola.c:458
 sctp_inq_push+0x1ea/0x290 net/sctp/inqueue.c:95
 sctp_rcv+0x2818/0x3570 net/sctp/input.c:271
 sctp6_rcv+0x17/0x30 net/sctp/ipv6.c:1063
 ip6_protocol_deliver_rcu+0x303/0x16c0 net/ipv6/ip6_input.c:394
 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:434
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 ip6_input+0xe4/0x3f0 net/ipv6/ip6_input.c:443
 dst_input include/net/dst.h:450 [inline]
 ip6_rcv_finish+0x1e7/0x320 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 ipv6_rcv+0x10e/0x420 net/ipv6/ip6_input.c:272
 __netif_receive_skb_one_core+0x115/0x1a0 net/core/dev.c:4973
 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083
 process_backlog+0x206/0x750 net/core/dev.c:5923
 napi_poll net/core/dev.c:6346 [inline]
 net_rx_action+0x4fa/0x1070 net/core/dev.c:6412
 __do_softirq+0x266/0x95a kernel/softirq.c:293

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8880a46bbac0
 which belongs to the cache ip6_dst_cache of size 224
The buggy address is located 10 bytes to the right of
 224-byte region [ffff8880a46bbac0, ffff8880a46bbba0)
The buggy address belongs to the page:
page:ffffea000291aec0 count:1 mapcount:0 mapping:ffff88821692f980 index:0xffff8880a46bb840
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea0002492cc8 ffffea0002840b88 ffff88821692f980
raw: ffff8880a46bb840 ffff8880a46bb0c0 0000000100000005 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a46bba80: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
 ffff8880a46bbb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880a46bbb80: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc
                                  ^
 ffff8880a46bbc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880a46bbc80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/03/23 13:46 net-old c8248c6c1a3d 3361bde5 .config console log report ci-upstream-net-this-kasan-gce
2019/02/01 13:50 net-old 5e66e35aab33 0c07abcf .config console log report ci-upstream-net-this-kasan-gce
* Struck through repros no longer work on HEAD.