==================================================================
BUG: KCSAN: data-race in lookup_user_key / lookup_user_key

write to 0xffff8880a4e5be18 of 4 bytes by task 23407 on cpu 0:
 get_cred include/linux/cred.h:253 [inline]
 lookup_user_key+0xc6/0xb30 security/keys/process_keys.c:626
 __do_sys_add_key security/keys/keyctl.c:124 [inline]
 __se_sys_add_key security/keys/keyctl.c:72 [inline]
 __x64_sys_add_key+0x1a2/0x380 security/keys/keyctl.c:72
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8880a4e5be18 of 4 bytes by task 23408 on cpu 1:
 get_cred include/linux/cred.h:253 [inline]
 lookup_user_key+0xc6/0xb30 security/keys/process_keys.c:626
 __do_sys_add_key security/keys/keyctl.c:124 [inline]
 __se_sys_add_key security/keys/keyctl.c:72 [inline]
 __x64_sys_add_key+0x1a2/0x380 security/keys/keyctl.c:72
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 23408 Comm: syz-executor.4 Not tainted 5.4.0-rc3+ #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: 23408 Comm: syz-executor.4 Not tainted 5.4.0-rc3+ #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+0xf5/0x159 lib/dump_stack.c:113
 panic+0x210/0x640 kernel/panic.c:221
 kcsan_report.cold+0xc/0x10 kernel/kcsan/report.c:302
 __kcsan_setup_watchpoint+0x32e/0x4a0 kernel/kcsan/core.c:411
 __tsan_write4 kernel/kcsan/kcsan.c:35 [inline]
 __tsan_write4+0x32/0x40 kernel/kcsan/kcsan.c:35
 get_cred include/linux/cred.h:253 [inline]
 lookup_user_key+0xc6/0xb30 security/keys/process_keys.c:626
 __do_sys_add_key security/keys/keyctl.c:124 [inline]
 __se_sys_add_key security/keys/keyctl.c:72 [inline]
 __x64_sys_add_key+0x1a2/0x380 security/keys/keyctl.c:72
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x459ef9
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fbfd7372c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459ef9
RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000020000180
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbfd73736d4
R13: 00000000004c00a9 R14: 00000000004d2220 R15: 00000000ffffffff
Kernel Offset: disabled
Rebooting in 86400 seconds..