KCSAN: data-race in avc_policy_seqno / avc_ss

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in avc_policy_seqno / avc_ss_reset selinux				1	86d	86d	0/28	auto-obsoleted due to no activity on 2024/09/30 10:46

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BUG: KCSAN: data-race in avc_policy_seqno / avc_ss_reset

write to 0xffffffff88bffa48 of 4 bytes by task 7810 on cpu 0:
 avc_latest_notif_update security/selinux/avc.c:576 [inline]
 avc_ss_reset+0x218/0x250 security/selinux/avc.c:965
 selinux_notify_policy_change security/selinux/ss/services.c:2182 [inline]
 security_set_bools+0x30b/0x350 security/selinux/ss/services.c:3101
 sel_commit_bools_write+0x1de/0x260 security/selinux/selinuxfs.c:1332
 do_loop_readv_writev fs/read_write.c:843 [inline]
 vfs_writev+0x3fb/0x880 fs/read_write.c:1052
 do_writev+0xf4/0x220 fs/read_write.c:1096
 __do_sys_writev fs/read_write.c:1164 [inline]
 __se_sys_writev fs/read_write.c:1161 [inline]
 __x64_sys_writev+0x45/0x50 fs/read_write.c:1161
 x64_sys_call+0x1fab/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff88bffa48 of 4 bytes by task 3016 on cpu 1:
 avc_policy_seqno+0x15/0x20 security/selinux/avc.c:1200
 selinux_file_permission+0x216/0x360 security/selinux/hooks.c:3638
 security_file_permission+0x3d/0x80 security/security.c:2840
 iterate_dir+0x5b/0x310 fs/readdir.c:93
 __do_sys_getdents64 fs/readdir.c:403 [inline]
 __se_sys_getdents64+0x87/0x1a0 fs/readdir.c:389
 __x64_sys_getdents64+0x43/0x50 fs/readdir.c:389
 x64_sys_call+0x2d24/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:218
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000143 -> 0x00000144

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3016 Comm: udevd Not tainted 6.12.0-syzkaller-01892-g8f7c8b88bda4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
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