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KCSAN: data-race in dequeue_signal / ptrace_check_attach (5)

Status: auto-obsoleted due to no activity on 2023/10/08 11:58
Subsystems: kernel
[Documentation on labels]
First crash: 378d, last: 315d
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in dequeue_signal / ptrace_check_attach (6) kernel 1 276d 276d 0/27 auto-obsoleted due to no activity on 2023/11/16 03:30
upstream KCSAN: data-race in dequeue_signal / ptrace_check_attach (7) kernel 13 112d 215d 0/27 auto-obsoleted due to no activity on 2024/04/27 21:52
upstream KCSAN: data-race in dequeue_signal / ptrace_check_attach (3) kernel 3 500d 525d 0/27 auto-obsoleted due to no activity on 2023/04/16 11:35
upstream KCSAN: data-race in dequeue_signal / ptrace_check_attach (2) kernel 1 570d 570d 0/27 auto-obsoleted due to no activity on 2023/02/02 07:54
upstream KCSAN: data-race in dequeue_signal / ptrace_check_attach kernel 1 673d 673d 0/27 auto-obsoleted due to no activity on 2022/10/15 10:03
upstream KCSAN: data-race in dequeue_signal / ptrace_check_attach (4) kernel 2 439d 448d 0/27 auto-obsoleted due to no activity on 2023/06/06 04:16
upstream KCSAN: data-race in dequeue_signal / ptrace_check_attach (8) kernel 2 57d 77d 0/27 auto-obsoleted due to no activity on 2024/06/22 14:38

Sample crash report:
==================================================================
BUG: KCSAN: data-race in dequeue_signal / ptrace_check_attach

read-write to 0xffff888142dfd640 of 8 bytes by task 3757 on cpu 1:
 dequeue_signal+0x3ca/0x420 kernel/signal.c:694
 get_signal+0x366/0x1090 kernel/signal.c:2772
 arch_do_signal_or_restart+0x95/0x4b0 arch/x86/kernel/signal.c:309
 exit_to_user_mode_loop+0x6f/0xe0 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:296
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888142dfd640 of 8 bytes by task 3719 on cpu 0:
 ptrace_freeze_traced kernel/ptrace.c:200 [inline]
 ptrace_check_attach+0x7e/0x280 kernel/ptrace.c:267
 __do_sys_ptrace kernel/ptrace.c:1300 [inline]
 __se_sys_ptrace+0xd4/0x2a0 kernel/ptrace.c:1278
 __x64_sys_ptrace+0x55/0x60 kernel/ptrace.c:1278
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000000000 -> 0x0000000008010000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3719 Comm: syz-executor.1 Not tainted 6.5.0-syzkaller-11075-g92901222f83d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/09/03 11:48 upstream 92901222f83d 696ea0d2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dequeue_signal / ptrace_check_attach
2023/08/03 12:16 upstream ec351c8f2e62 39a91c18 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dequeue_signal / ptrace_check_attach
2023/07/02 15:56 upstream 995b406c7e97 bfc47836 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dequeue_signal / ptrace_check_attach
* Struck through repros no longer work on HEAD.