syzbot


KCSAN: data-race in capable / prepare_signal

Status: auto-closed as invalid on 2021/06/28 00:37
Subsystems: kernel
[Documentation on labels]
First crash: 1076d, last: 1068d

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

write to 0xffff888150ffd06c of 4 bytes by task 15866 on cpu 0:
 ns_capable_common kernel/capability.c:377 [inline]
 ns_capable kernel/capability.c:396 [inline]
 capable+0x85/0xb0 kernel/capability.c:449
 io_uring_create+0x73f/0x18d0 fs/io_uring.c:9615
 io_uring_setup fs/io_uring.c:9716 [inline]
 __do_sys_io_uring_setup fs/io_uring.c:9722 [inline]
 __se_sys_io_uring_setup fs/io_uring.c:9719 [inline]
 __x64_sys_io_uring_setup+0xe1/0x120 fs/io_uring.c:9719
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888150ffd06c of 4 bytes by task 15862 on cpu 1:
 sig_task_ignored kernel/signal.c:93 [inline]
 sig_ignored kernel/signal.c:118 [inline]
 prepare_signal+0x952/0xeb0 kernel/signal.c:1001
 __send_signal+0x64/0x760 kernel/signal.c:1121
 send_signal+0x281/0x390 kernel/signal.c:1284
 __group_send_sig_info kernel/signal.c:1323 [inline]
 do_notify_parent_cldstop+0x222/0x280 kernel/signal.c:2120
 ptrace_stop+0x2e2/0x670 kernel/signal.c:2254
 ptrace_do_notify kernel/signal.c:2321 [inline]
 ptrace_notify+0x107/0x180 kernel/signal.c:2331
 ptrace_report_syscall include/linux/tracehook.h:66 [inline]
 tracehook_report_syscall_entry include/linux/tracehook.h:105 [inline]
 arch_syscall_enter_tracehook include/linux/entry-common.h:98 [inline]
 syscall_trace_enter+0x87/0x290 kernel/entry/common.c:60
 __syscall_enter_from_user_work kernel/entry/common.c:89 [inline]
 syscall_enter_from_user_mode+0x1c/0x20 kernel/entry/common.c:107
 do_syscall_64+0x27/0x90 arch/x86/entry/common.c:42
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 15862 Comm: syz-executor.1 Tainted: G        W         5.13.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/05/24 00:36 upstream 6ebb6814a1ef 3c7fef33 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in capable / prepare_signal
2021/05/15 21:12 upstream 25a1298726e9 93f844de .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in capable / prepare_signal
* Struck through repros no longer work on HEAD.