syzbot


KCSAN: data-race in do_syslog / log_store

Status: auto-closed as invalid on 2020/11/17 21:56
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+8f5c0f7fd3c70ea71b5c@syzkaller.appspotmail.com
First crash: 1619d, last: 1262d

Sample crash report:
==================================================================
BUG: KCSAN: data-race in do_syslog / log_store

write to 0xffffffff88f8e1c0 of 8 bytes by task 8705 on cpu 0:
 log_store+0x7a2/0x7d0 kernel/printk/printk.c:672
 log_output kernel/printk/printk.c:1932 [inline]
 vprintk_store+0x5ba/0x700 kernel/printk/printk.c:1983
 vprintk_emit+0x114/0x4f0 kernel/printk/printk.c:2011
 vprintk_default+0x24/0x30 kernel/printk/printk.c:2047
 vprintk_func+0x13d/0x140 kernel/printk/printk_safe.c:393
 printk+0x62/0x82 kernel/printk/printk.c:2078
 hsr_debugfs_init+0x90/0xd0 net/hsr/hsr_debugfs.c:108
 hsr_dev_finalize+0x452/0x490 net/hsr/hsr_device.c:579
 hsr_newlink+0x384/0x3c0 net/hsr/hsr_netlink.c:102
 __rtnl_newlink net/core/rtnetlink.c:3441 [inline]
 rtnl_newlink+0xdaf/0x1340 net/core/rtnetlink.c:3500
 rtnetlink_rcv_msg+0x71b/0x7b0 net/core/rtnetlink.c:5563
 netlink_rcv_skb+0x13e/0x240 net/netlink/af_netlink.c:2470
 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:5581
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x5e2/0x6b0 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x6d8/0x7a0 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 __sys_sendto+0x2ae/0x380 net/socket.c:1992
 __do_sys_sendto net/socket.c:2004 [inline]
 __se_sys_sendto net/socket.c:2000 [inline]
 __x64_sys_sendto+0x74/0x90 net/socket.c:2000
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffffffff88f8e1c0 of 8 bytes by task 8328 on cpu 1:
 do_syslog+0x3b2/0x1480 kernel/printk/printk.c:1561
 kmsg_read+0x7a/0xa0 fs/proc/kmsg.c:40
 pde_read fs/proc/inode.c:306 [inline]
 proc_reg_read+0xde/0x1a0 fs/proc/inode.c:316
 vfs_read+0x16d/0x5f0 fs/read_write.c:479
 ksys_read+0xce/0x180 fs/read_write.c:615
 __do_sys_read fs/read_write.c:625 [inline]
 __se_sys_read fs/read_write.c:623 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:623
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8328 Comm: in:imklog Not tainted 5.9.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (583):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/10/13 21:55 upstream 6ad4bf6ea160 fc7735a2 .config console log report info ci2-upstream-kcsan-gce
2020/10/13 09:24 upstream 865c50e1d279 bd69ee0d .config console log report info ci2-upstream-kcsan-gce
2020/10/12 19:45 upstream 1e6d1d96461e d32b0bbf .config console log report info ci2-upstream-kcsan-gce
2020/10/12 16:28 upstream bbf5c979011a d32b0bbf .config console log report info ci2-upstream-kcsan-gce
2020/10/12 10:19 upstream bbf5c979011a 4a77ae0b .config console log report info ci2-upstream-kcsan-gce
2020/10/11 19:17 upstream 3dd0130f2430 4a77ae0b .config console log report info ci2-upstream-kcsan-gce
2020/10/10 23:51 upstream da690031a5d6 4a77ae0b .config console log report info ci2-upstream-kcsan-gce
2020/10/10 22:23 upstream 6f2f486d57c4 4a77ae0b .config console log report info ci2-upstream-kcsan-gce
2020/10/10 09:58 upstream 6f2f486d57c4 b74c49a6 .config console log report info ci2-upstream-kcsan-gce
2020/10/09 22:02 upstream 8a5f78d98c26 93817d89 .config console log report info ci2-upstream-kcsan-gce
2020/10/09 14:56 upstream 583090b1b823 fa79ed2a .config console log report info ci2-upstream-kcsan-gce
2020/10/08 20:15 upstream 3d006ee42dde 92390980 .config console log report info ci2-upstream-kcsan-gce
2020/10/08 10:33 upstream c85fb28b6f99 92390980 .config console log report info ci2-upstream-kcsan-gce
2020/10/06 23:09 upstream c85fb28b6f99 1880b4a9 .config console log report info ci2-upstream-kcsan-gce
2020/10/05 21:21 upstream 7575fdda569b 1880b4a9 .config console log report info ci2-upstream-kcsan-gce
2020/10/05 18:46 upstream 549738f15da0 1880b4a9 .config console log report info ci2-upstream-kcsan-gce
2020/10/05 00:19 upstream 549738f15da0 5ef9c291 .config console log report info ci2-upstream-kcsan-gce
2020/10/04 11:45 upstream 22fbc037cd32 5ef9c291 .config console log report info ci2-upstream-kcsan-gce
2020/10/04 04:39 upstream 22fbc037cd32 1a3f9408 .config console log report info ci2-upstream-kcsan-gce
2020/10/03 03:52 upstream d3d45f8220d6 2653fa43 .config console log report info ci2-upstream-kcsan-gce
2020/10/02 12:45 upstream 472e5b056f00 9602ddf4 .config console log report info ci2-upstream-kcsan-gce
2020/10/01 20:25 upstream fcadab740480 4103fce0 .config console log report info ci2-upstream-kcsan-gce
2020/10/01 08:26 upstream 60e720931556 4103fce0 .config console log report info ci2-upstream-kcsan-gce
2020/09/30 22:17 upstream 60e720931556 a9767fb2 .config console log report info ci2-upstream-kcsan-gce
2020/09/30 19:08 upstream 02de58b24d2e a9767fb2 .config console log report info ci2-upstream-kcsan-gce
2020/09/30 07:02 upstream 02de58b24d2e 8516f6d3 .config console log report info ci2-upstream-kcsan-gce
2020/09/29 14:34 upstream fb0155a09b02 5abc3f1a .config console log report info ci2-upstream-kcsan-gce
2020/09/29 00:00 upstream fb0155a09b02 1b88c6d5 .config console log report info ci2-upstream-kcsan-gce
2020/09/28 09:07 upstream a1b8638ba132 6bfdbe89 .config console log report info ci2-upstream-kcsan-gce
2020/09/28 02:08 upstream a1b8638ba132 5dd8aee8 .config console log report info ci2-upstream-kcsan-gce
2020/09/27 14:53 upstream a1bffa48745a 5dd8aee8 .config console log report info ci2-upstream-kcsan-gce
2020/09/27 01:55 upstream eeddbe6841cd 5dd8aee8 .config console log report info ci2-upstream-kcsan-gce
2020/09/26 18:51 upstream eeddbe6841cd 2d5ea0cb .config console log report info ci2-upstream-kcsan-gce
2020/09/26 11:18 upstream 7c7ec3226f5f 2d5ea0cb .config console log report info ci2-upstream-kcsan-gce
2020/09/26 04:06 upstream 7c7ec3226f5f 4a006f63 .config console log report info ci2-upstream-kcsan-gce
2020/09/26 00:35 upstream 171d4ff79f96 4a006f63 .config console log report info ci2-upstream-kcsan-gce
2020/09/24 17:01 upstream 171d4ff79f96 54289b08 .config console log report info ci2-upstream-kcsan-gce
2020/09/24 00:53 upstream c9c9e6a49f89 54289b08 .config console log report info ci2-upstream-kcsan-gce
2020/09/23 20:15 upstream 805c6d3c1921 54289b08 .config console log report info ci2-upstream-kcsan-gce
2020/09/23 11:15 upstream 805c6d3c1921 287cd75a .config console log report info ci2-upstream-kcsan-gce
2020/09/22 16:58 upstream eff48ddeab78 3e8f6c27 .config console log report info ci2-upstream-kcsan-gce
2020/09/22 08:40 upstream 98477740630f 3e8f6c27 .config console log report info ci2-upstream-kcsan-gce
2020/09/21 22:11 upstream 98477740630f 9e1fa68e .config console log report info ci2-upstream-kcsan-gce
2019/10/23 02:52 https://github.com/google/ktsan.git kcsan 05f2236801fe d0686497 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.