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KCSAN: data-race in tcp_add_backlog / tcp_recvmsg (2)

Status: fixed on 2019/12/13 00:31
Subsystems: net
[Documentation on labels]
Fix commit: 9ed498c6280a net-backports: net: silence data-races on sk_backlog.tail
First crash: 1635d, last: 1597d
▶ ▼ Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in tcp_add_backlog / tcp_recvmsg net 17719 1636d 1666d 13/26 fixed on 2019/11/04 14:50

Sample crash report:
==================================================================
BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg

write to 0xffff888122a412f8 of 8 bytes by interrupt on cpu 0:
 __sk_add_backlog include/net/sock.h:907 [inline]
 sk_add_backlog include/net/sock.h:938 [inline]
 tcp_add_backlog+0x476/0xce0 net/ipv4/tcp_ipv4.c:1759
 tcp_v4_rcv+0x1a70/0x1bd0 net/ipv4/tcp_ipv4.c:1947
 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204
 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:442 [inline]
 ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:4929
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5043
 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5133
 napi_skb_finish net/core/dev.c:5596 [inline]
 napi_gro_receive+0x28f/0x330 net/core/dev.c:5629
 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061
 virtnet_receive drivers/net/virtio_net.c:1323 [inline]
 virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428
 napi_poll net/core/dev.c:6311 [inline]
 net_rx_action+0x3ae/0xa90 net/core/dev.c:6379
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 run_ksoftirqd+0x46/0x60 kernel/softirq.c:603
 smpboot_thread_fn+0x37d/0x4a0 kernel/smpboot.c:165
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

read to 0xffff888122a412f8 of 8 bytes by task 7485 on cpu 1:
 tcp_recvmsg+0x46e/0x1b40 net/ipv4/tcp.c:2050
 inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838
 sock_recvmsg_nosec net/socket.c:871 [inline]
 sock_recvmsg net/socket.c:889 [inline]
 sock_recvmsg+0x92/0xb0 net/socket.c:885
 sock_read_iter+0x15f/0x1e0 net/socket.c:967
 call_read_iter include/linux/fs.h:1889 [inline]
 new_sync_read+0x389/0x4f0 fs/read_write.c:414
 __vfs_read+0xb1/0xc0 fs/read_write.c:427
 vfs_read fs/read_write.c:461 [inline]
 vfs_read+0x143/0x2c0 fs/read_write.c:446
 ksys_read+0xd5/0x1b0 fs/read_write.c:587
 __do_sys_read fs/read_write.c:597 [inline]
 __se_sys_read fs/read_write.c:595 [inline]
 __x64_sys_read+0x4c/0x60 fs/read_write.c:595
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7485 Comm: syz-fuzzer Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (47):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/12 17:22 https://github.com/google/ktsan.git kcsan ef798c30ba4e 08003f64 .config console log report ci2-upstream-kcsan-gce
2019/12/12 05:18 https://github.com/google/ktsan.git kcsan ef798c30ba4e d973f528 .config console log report ci2-upstream-kcsan-gce
2019/12/11 14:09 https://github.com/google/ktsan.git kcsan ef798c30ba4e 0d368675 .config console log report ci2-upstream-kcsan-gce
2019/12/10 20:58 https://github.com/google/ktsan.git kcsan ef798c30ba4e 101194eb .config console log report ci2-upstream-kcsan-gce
2019/12/10 03:59 https://github.com/google/ktsan.git kcsan ef798c30ba4e 4b83c8fb .config console log report ci2-upstream-kcsan-gce
2019/12/09 13:40 https://github.com/google/ktsan.git kcsan ef798c30ba4e b31eda3d .config console log report ci2-upstream-kcsan-gce
2019/12/09 13:40 https://github.com/google/ktsan.git kcsan ef798c30ba4e b31eda3d .config console log report ci2-upstream-kcsan-gce
2019/12/07 19:22 https://github.com/google/ktsan.git kcsan ef798c30ba4e 1508f453 .config console log report ci2-upstream-kcsan-gce
2019/12/06 16:03 https://github.com/google/ktsan.git kcsan ef798c30ba4e 85f26751 .config console log report ci2-upstream-kcsan-gce
2019/12/06 10:41 https://github.com/google/ktsan.git kcsan ef798c30ba4e 12c3b6cd .config console log report ci2-upstream-kcsan-gce
2019/12/06 00:07 https://github.com/google/ktsan.git kcsan ef798c30ba4e 98b4ef2d .config console log report ci2-upstream-kcsan-gce
2019/12/05 10:43 https://github.com/google/ktsan.git kcsan ef798c30ba4e 9fd5a512 .config console log report ci2-upstream-kcsan-gce
2019/12/05 10:43 https://github.com/google/ktsan.git kcsan ef798c30ba4e 9fd5a512 .config console log report ci2-upstream-kcsan-gce
2019/12/04 13:58 https://github.com/google/ktsan.git kcsan ef798c30ba4e b2088328 .config console log report ci2-upstream-kcsan-gce
2019/12/04 13:54 https://github.com/google/ktsan.git kcsan ef798c30ba4e b2088328 .config console log report ci2-upstream-kcsan-gce
2019/12/03 19:11 https://github.com/google/ktsan.git kcsan ef798c30ba4e 0ecb9746 .config console log report ci2-upstream-kcsan-gce
2019/12/02 18:04 https://github.com/google/ktsan.git kcsan ef798c30ba4e ab342da3 .config console log report ci2-upstream-kcsan-gce
2019/12/01 20:27 https://github.com/google/ktsan.git kcsan ef798c30ba4e f879db37 .config console log report ci2-upstream-kcsan-gce
2019/11/30 21:09 https://github.com/google/ktsan.git kcsan ef798c30ba4e a76bf83f .config console log report ci2-upstream-kcsan-gce
2019/11/30 01:16 https://github.com/google/ktsan.git kcsan ef798c30ba4e 3a75be00 .config console log report ci2-upstream-kcsan-gce
2019/11/29 10:21 https://github.com/google/ktsan.git kcsan ef798c30ba4e 4f7e1d0f .config console log report ci2-upstream-kcsan-gce
2019/11/28 22:08 https://github.com/google/ktsan.git kcsan ef798c30ba4e 76357d6f .config console log report ci2-upstream-kcsan-gce
2019/11/28 09:47 https://github.com/google/ktsan.git kcsan ef798c30ba4e 97264cb1 .config console log report ci2-upstream-kcsan-gce
2019/11/27 16:03 https://github.com/google/ktsan.git kcsan ef798c30ba4e 0d63f89c .config console log report ci2-upstream-kcsan-gce
2019/11/26 19:51 https://github.com/google/ktsan.git kcsan ef798c30ba4e 1048481f .config console log report ci2-upstream-kcsan-gce
2019/11/22 10:25 https://github.com/google/ktsan.git kcsan 5863cc791e4c 598ca6c8 .config console log report ci2-upstream-kcsan-gce
2019/11/20 22:09 https://github.com/google/ktsan.git kcsan 5863cc791e4c 8098ea0f .config console log report ci2-upstream-kcsan-gce
2019/11/19 08:53 https://github.com/google/ktsan.git kcsan 5863cc791e4c 432c7650 .config console log report ci2-upstream-kcsan-gce
2019/11/17 08:43 https://github.com/google/ktsan.git kcsan 5863cc791e4c d5696d51 .config console log report ci2-upstream-kcsan-gce
2019/11/16 05:20 https://github.com/google/ktsan.git kcsan 5863cc791e4c cdac920b .config console log report ci2-upstream-kcsan-gce
2019/11/15 08:36 https://github.com/google/ktsan.git kcsan 5863cc791e4c 79248ee8 .config console log report ci2-upstream-kcsan-gce
2019/11/12 08:25 https://github.com/google/ktsan.git kcsan 7f2955e0d056 048f2d49 .config console log report ci2-upstream-kcsan-gce
2019/11/11 15:56 https://github.com/google/ktsan.git kcsan 94c006602e13 377d77fa .config console log report ci2-upstream-kcsan-gce
2019/11/09 22:33 https://github.com/google/ktsan.git kcsan 94c006602e13 dc438b91 .config console log report ci2-upstream-kcsan-gce
2019/11/09 22:33 https://github.com/google/ktsan.git kcsan 94c006602e13 dc438b91 .config console log report ci2-upstream-kcsan-gce
2019/11/08 07:08 https://github.com/google/ktsan.git kcsan 94c006602e13 1e35461e .config console log report ci2-upstream-kcsan-gce
2019/11/07 15:24 https://github.com/google/ktsan.git kcsan 94c006602e13 f39aff9e .config console log report ci2-upstream-kcsan-gce
2019/11/07 14:54 https://github.com/google/ktsan.git kcsan 94c006602e13 d5bc6812 .config console log report ci2-upstream-kcsan-gce
2019/11/07 02:51 https://github.com/google/ktsan.git kcsan 94c006602e13 d797d201 .config console log report ci2-upstream-kcsan-gce
2019/11/06 14:37 https://github.com/google/ktsan.git kcsan 94c006602e13 da505f84 .config console log report ci2-upstream-kcsan-gce
2019/11/06 02:30 https://github.com/google/ktsan.git kcsan 94c006602e13 bc2c6e45 .config console log report ci2-upstream-kcsan-gce
2019/11/05 14:22 https://github.com/google/ktsan.git kcsan 94c006602e13 af5c522d .config console log report ci2-upstream-kcsan-gce
2019/11/05 12:09 https://github.com/google/ktsan.git kcsan 94c006602e13 0f3ec414 .config console log report ci2-upstream-kcsan-gce
2019/11/05 12:09 https://github.com/google/ktsan.git kcsan 94c006602e13 0f3ec414 .config console log report ci2-upstream-kcsan-gce
2019/11/05 00:04 https://github.com/google/ktsan.git kcsan 94c006602e13 76630fc9 .config console log report ci2-upstream-kcsan-gce
2019/11/04 14:57 https://github.com/google/ktsan.git kcsan 94c006602e13 18e12644 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.