syzbot


KCSAN: data-race in ipc_set_key_private / selinux_shm_shmctl

Status: auto-obsoleted due to no activity on 2024/04/02 05:31
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+4ef6c25720bf4c579fcf@syzkaller.appspotmail.com
First crash: 56d, last: 56d

Sample crash report:
==================================================================
BUG: KCSAN: data-race in ipc_set_key_private / selinux_shm_shmctl

write to 0xffff88816242ba0c of 4 bytes by task 2538 on cpu 0:
 ipc_set_key_private+0x26/0x40 ipc/util.c:525
 do_shm_rmid ipc/shm.c:133 [inline]
 shmctl_down+0x15b/0x1e0 ipc/shm.c:1019
 ksys_shmctl ipc/shm.c:1286 [inline]
 __do_sys_shmctl ipc/shm.c:1297 [inline]
 __se_sys_shmctl+0x28f/0x400 ipc/shm.c:1295
 __x64_sys_shmctl+0x43/0x50 ipc/shm.c:1295
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff88816242ba0c of 4 bytes by task 2537 on cpu 1:
 ipc_has_perm security/selinux/hooks.c:6008 [inline]
 selinux_shm_shmctl+0x193/0x260 security/selinux/hooks.c:6212
 security_shm_shmctl+0x3f/0x70 security/security.c:3781
 shmctl_do_lock+0x95/0x450 ipc/shm.c:1179
 ksys_shmctl ipc/shm.c:1289 [inline]
 __do_sys_shmctl ipc/shm.c:1297 [inline]
 __se_sys_shmctl+0x262/0x400 ipc/shm.c:1295
 __x64_sys_shmctl+0x43/0x50 ipc/shm.c:1295
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x798dd821 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 2537 Comm: syz-executor.3 Tainted: G        W          6.8.0-rc6-syzkaller-00011-g45ec2f5f6ed3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/02/27 05:30 upstream 45ec2f5f6ed3 05e69c83 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ipc_set_key_private / selinux_shm_shmctl
* Struck through repros no longer work on HEAD.