==================================================================
BUG: KCSAN: data-race in get_signal / ptrace_attach
write to 0xffff88807a210024 of 4 bytes by task 21415 on cpu 0:
get_signal+0xd41/0x1520 kernel/signal.c:2719
do_signal+0x25/0x270 arch/x86/kernel/signal.c:810
exit_to_usermode_loop arch/x86/entry/common.c:212 [inline]
__prepare_exit_to_usermode+0x127/0x230 arch/x86/entry/common.c:246
__syscall_return_slowpath+0x47/0x60 arch/x86/entry/common.c:329
do_syscall_64+0x5d/0xb0 arch/x86/entry/common.c:368
entry_SYSCALL_64_after_hwframe+0x44/0xa9
read to 0xffff88807a210024 of 4 bytes by task 21413 on cpu 1:
ptrace_attach+0xd0/0x4b0 kernel/ptrace.c:384
__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+0x51/0xb0 arch/x86/entry/common.c:359
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 21413 Comm: syz-executor.5 Not tainted 5.8.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 21413 Comm: syz-executor.5 Not tainted 5.8.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x10f/0x19d lib/dump_stack.c:118
panic+0x207/0x64a kernel/panic.c:231
kcsan_report+0x684/0x690 kernel/kcsan/report.c:626
kcsan_setup_watchpoint+0x453/0x4d0 kernel/kcsan/core.c:519
ptrace_attach+0xd0/0x4b0 kernel/ptrace.c:384
__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+0x51/0xb0 arch/x86/entry/common.c:359
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cb29
Code: Bad RIP value.
RSP: 002b:00007f43d462fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000065
RAX: ffffffffffffffda RBX: 00000000004fbc60 RCX: 000000000045cb29
RDX: 0000000000000000 RSI: 0000000000000501 RDI: 0000000000004206
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000898 R14: 00000000004cb8e2 R15: 00007f43d46306d4
Kernel Offset: disabled
Rebooting in 86400 seconds..