syzbot


KCSAN: data-race in prepare_signal / ptrace_attach (2)

Status: auto-closed as invalid on 2020/10/13 05:51
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 742d, last: 707d
similar bugs (7):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in prepare_signal / ptrace_attach (5) 2 390d 404d 0/23 auto-closed as invalid on 2021/08/26 15:59
upstream KCSAN: data-race in prepare_signal / ptrace_attach 1 783d 783d 0/23 auto-closed as invalid on 2020/07/29 00:33
upstream KCSAN: data-race in prepare_signal / ptrace_attach (6) 1 233d 233d 0/23 auto-closed as invalid on 2022/01/30 21:35
upstream KCSAN: data-race in prepare_signal / ptrace_attach (7) 1 170d 170d 0/23 auto-closed as invalid on 2022/04/03 14:09
upstream KCSAN: data-race in prepare_signal / ptrace_attach (8) 1 92d 92d 0/23 auto-closed as invalid on 2022/06/20 14:20
upstream KCSAN: data-race in prepare_signal / ptrace_attach (4) 1 474d 474d 0/23 auto-closed as invalid on 2021/06/03 07:49
upstream KCSAN: data-race in prepare_signal / ptrace_attach (3) 2 568d 603d 0/23 auto-closed as invalid on 2021/03/01 09:38

Sample crash report:
==================================================================
BUG: KCSAN: data-race in prepare_signal / ptrace_attach

write to 0xffff88807ac17068 of 4 bytes by task 16223 on cpu 0:
 ptrace_attach+0x217/0x4b0 kernel/ptrace.c:413
 __do_sys_ptrace kernel/ptrace.c:1262 [inline]
 __se_sys_ptrace+0xc1/0x2d0 kernel/ptrace.c:1242
 __x64_sys_ptrace+0x51/0x60 kernel/ptrace.c:1242
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88807ac17068 of 4 bytes by task 16224 on cpu 1:
 sig_ignored kernel/signal.c:116 [inline]
 prepare_signal+0x791/0xdb0 kernel/signal.c:961
 __send_signal+0x64/0x7d0 kernel/signal.c:1081
 send_signal+0x398/0x3e0 kernel/signal.c:1241
 do_send_sig_info+0x9b/0xe0 kernel/signal.c:1290
 do_send_specific kernel/signal.c:3798 [inline]
 do_tkill kernel/signal.c:3824 [inline]
 __do_sys_tkill kernel/signal.c:3859 [inline]
 __se_sys_tkill+0x12e/0x180 kernel/signal.c:3853
 __x64_sys_tkill+0x2d/0x40 kernel/signal.c:3853
 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: 16224 Comm: syz-executor.4 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (3):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2020/09/08 05:49 upstream f4d51dffc6c0 abf9ba4f .config log report
ci2-upstream-kcsan-gce 2020/09/02 16:26 upstream 9c7d619be5a0 abf9ba4f .config log report
ci2-upstream-kcsan-gce 2020/08/04 00:58 upstream e4cbce4d1317 96dd3623 .config log report