syzbot


KCSAN: data-race in audit_log_start / audit_receive

Status: auto-closed as invalid on 2022/01/10 10:36
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 366d, last: 366d

Sample crash report:
==================================================================
BUG: KCSAN: data-race in audit_log_start / audit_receive

write to 0xffffffff86db6ba0 of 8 bytes by task 4506 on cpu 1:
 audit_ctl_lock kernel/audit.c:237 [inline]
 audit_receive+0x6e/0x2600 kernel/audit.c:1535
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x5fc/0x6c0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x726/0x840 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg net/socket.c:724 [inline]
 kernel_sendmsg+0x97/0xd0 net/socket.c:744
 sock_no_sendpage+0x84/0xb0 net/core/sock.c:3080
 kernel_sendpage+0x187/0x200 net/socket.c:3504
 sock_sendpage+0x5a/0x70 net/socket.c:1003
 pipe_to_sendpage+0x128/0x160 fs/splice.c:364
 splice_from_pipe_feed fs/splice.c:418 [inline]
 __splice_from_pipe+0x207/0x500 fs/splice.c:562
 splice_from_pipe fs/splice.c:597 [inline]
 generic_splice_sendpage+0x94/0xd0 fs/splice.c:746
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffffff86db6ba0 of 8 bytes by task 4503 on cpu 0:
 audit_ctl_owner_current kernel/audit.c:258 [inline]
 audit_log_start+0x125/0x6b0 kernel/audit.c:1829
 audit_seccomp+0x47/0x120 kernel/auditsc.c:2953
 seccomp_log kernel/seccomp.c:985 [inline]
 __seccomp_filter+0xdf5/0xe40 kernel/seccomp.c:1281
 __secure_computing+0xfb/0x190 kernel/seccomp.c:1311
 syscall_trace_enter+0x120/0x2b0 kernel/entry/common.c:68
 __syscall_enter_from_user_work kernel/entry/common.c:90 [inline]
 syscall_enter_from_user_mode+0x1c/0x20 kernel/entry/common.c:108
 do_syscall_64+0x25/0xd0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000000000 -> 0xffff8881324bb000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 4503 Comm: syz-executor.2 Not tainted 5.16.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/12/06 10:30 upstream 0fcfb00b28c0 579a8754 .config log report info KCSAN: data-race in audit_log_start / audit_receive
* Struck through repros no longer work on HEAD.