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KCSAN: data-race in tcp_poll / tcp_recvmsg

Status: closed as invalid on 2019/10/15 15:50
Subsystems: net
[Documentation on labels]
First crash: 1701d, last: 1691d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in tcp_poll / tcp_recvmsg (2) net 22 1684d 1689d 13/26 fixed on 2019/11/04 14:50

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

read to 0xffff888125ff77b4 of 4 bytes by task 7402 on cpu 0:
 tcp_poll+0x1cc/0x6b0 net/ipv4/tcp.c:549
 sock_poll+0xed/0x250 net/socket.c:1256
 vfs_poll include/linux/poll.h:90 [inline]
 ep_item_poll.isra.0+0x90/0x190 fs/eventpoll.c:892
 ep_send_events_proc+0x113/0x5c0 fs/eventpoll.c:1749
 ep_scan_ready_list.constprop.0+0x189/0x500 fs/eventpoll.c:704
 ep_send_events fs/eventpoll.c:1793 [inline]
 ep_poll+0xe3/0x900 fs/eventpoll.c:1930
 do_epoll_wait+0x162/0x180 fs/eventpoll.c:2294
 __do_sys_epoll_pwait fs/eventpoll.c:2325 [inline]
 __se_sys_epoll_pwait fs/eventpoll.c:2311 [inline]
 __x64_sys_epoll_pwait+0xcd/0x170 fs/eventpoll.c:2311
 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff888125ff77b4 of 4 bytes by task 7417 on cpu 1:
 tcp_recvmsg+0xd86/0x1a30 net/ipv4/tcp.c:2141
 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:1864 [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+0xcf/0x2f0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7417 Comm: syz-fuzzer Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (26):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/10/15 10:26 https://github.com/google/ktsan.git kcsan 81f95ec7998e 05ad7292 .config console log report ci2-upstream-kcsan-gce
2019/10/14 17:53 https://github.com/google/ktsan.git kcsan d724f94f63de a6aef847 .config console log report ci2-upstream-kcsan-gce
2019/10/14 12:36 https://github.com/google/ktsan.git kcsan d724f94f63de a6aef847 .config console log report ci2-upstream-kcsan-gce
2019/10/14 09:52 https://github.com/google/ktsan.git kcsan d724f94f63de a6aef847 .config console log report ci2-upstream-kcsan-gce
2019/10/13 16:20 https://github.com/google/ktsan.git kcsan d724f94f63de 2f661ec4 .config console log report ci2-upstream-kcsan-gce
2019/10/12 16:11 https://github.com/google/ktsan.git kcsan d724f94f63de 426631dd .config console log report ci2-upstream-kcsan-gce
2019/10/12 11:22 https://github.com/google/ktsan.git kcsan d724f94f63de 426631dd .config console log report ci2-upstream-kcsan-gce
2019/10/12 04:46 https://github.com/google/ktsan.git kcsan d724f94f63de 426631dd .config console log report ci2-upstream-kcsan-gce
2019/10/12 03:02 https://github.com/google/ktsan.git kcsan d724f94f63de 426631dd .config console log report ci2-upstream-kcsan-gce
2019/10/11 04:47 https://github.com/google/ktsan.git kcsan d724f94f63de 1a3bad90 .config console log report ci2-upstream-kcsan-gce
2019/10/11 02:25 https://github.com/google/ktsan.git kcsan d724f94f63de 1a3bad90 .config console log report ci2-upstream-kcsan-gce
2019/10/11 01:34 https://github.com/google/ktsan.git kcsan d724f94f63de 1a3bad90 .config console log report ci2-upstream-kcsan-gce
2019/10/10 14:27 https://github.com/google/ktsan.git kcsan d724f94f63de d52eff28 .config console log report ci2-upstream-kcsan-gce
2019/10/10 11:24 https://github.com/google/ktsan.git kcsan d724f94f63de d52eff28 .config console log report ci2-upstream-kcsan-gce
2019/10/10 05:11 https://github.com/google/ktsan.git kcsan d724f94f63de c4b9981b .config console log report ci2-upstream-kcsan-gce
2019/10/09 22:50 https://github.com/google/ktsan.git kcsan d724f94f63de c4b9981b .config console log report ci2-upstream-kcsan-gce
2019/10/09 16:08 https://github.com/google/ktsan.git kcsan d724f94f63de 312c6a5a .config console log report ci2-upstream-kcsan-gce
2019/10/09 12:39 https://github.com/google/ktsan.git kcsan d724f94f63de 312c6a5a .config console log report ci2-upstream-kcsan-gce
2019/10/09 05:41 https://github.com/google/ktsan.git kcsan d724f94f63de b1ebbfef .config console log report ci2-upstream-kcsan-gce
2019/10/08 08:37 https://github.com/google/ktsan.git kcsan c1c7521f03c7 28ac6e64 .config console log report ci2-upstream-kcsan-gce
2019/10/08 03:36 https://github.com/google/ktsan.git kcsan c1c7521f03c7 28ac6e64 .config console log report ci2-upstream-kcsan-gce
2019/10/07 16:53 https://github.com/google/ktsan.git kcsan c1c7521f03c7 28ac6e64 .config console log report ci2-upstream-kcsan-gce
2019/10/07 00:28 https://github.com/google/ktsan.git kcsan c1c7521f03c7 f3f7d9c8 .config console log report ci2-upstream-kcsan-gce
2019/10/06 23:44 https://github.com/google/ktsan.git kcsan c1c7521f03c7 f3f7d9c8 .config console log report ci2-upstream-kcsan-gce
2019/10/05 16:27 https://github.com/google/ktsan.git kcsan c1c7521f03c7 f3f7d9c8 .config console log report ci2-upstream-kcsan-gce
2019/10/05 08:23 https://github.com/google/ktsan.git kcsan c1c7521f03c7 f3f7d9c8 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.