[moderation] [selinux?] KCSAN: data-race in inode_doinit_with_dentry / inode_doinit_with_dentry (5)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b927546677c8 Merge tag 'dma-mapping-6.19-2025-12-22' of gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12e4ef1a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=b319ff1b6a2797ca
dashboard link: https://syzkaller.appspot.com/bug?extid=9ab96b38b76bec93939a
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
CC: [linux-...@vger.kernel.org omos...@redhat.com pa...@paul-moore.com sel...@vger.kernel.org stephen.sm...@gmail.com]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c9492a9b1448/disk-b9275466.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2cbc857ecf31/vmlinux-b9275466.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ee3537072ac2/bzImage-b9275466.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9ab96b...@syzkaller.appspotmail.com

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

write to 0xffff88812632ba7a of 1 bytes by task 4634 on cpu 1:
inode_doinit_with_dentry+0x285/0x7a0 security/selinux/hooks.c:1459
__inode_security_revalidate security/selinux/hooks.c:298 [inline]
inode_security security/selinux/hooks.c:332 [inline]
selinux_file_open+0xe4/0x330 security/selinux/hooks.c:4145
security_file_open+0x36/0x70 security/security.c:2636
do_dentry_open+0x216/0xa60 fs/open.c:939
vfs_open+0x37/0x1e0 fs/open.c:1094
dentry_open+0x4a/0x90 fs/open.c:1117
pidfs_alloc_file+0xe2/0x180 fs/pidfs.c:1079
pidfd_prepare+0x11d/0x170 kernel/fork.c:1900
pidfd_create kernel/pid.c:625 [inline]
__do_sys_pidfd_open kernel/pid.c:661 [inline]
__se_sys_pidfd_open+0x133/0x270 kernel/pid.c:646
__x64_sys_pidfd_open+0x31/0x40 kernel/pid.c:646
x64_sys_call+0x57c/0x3000 arch/x86/include/generated/asm/syscalls_64.h:435
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xca/0x2b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88812632ba7a of 1 bytes by task 4632 on cpu 0:
inode_doinit_with_dentry+0x74/0x7a0 security/selinux/hooks.c:1434
__inode_security_revalidate security/selinux/hooks.c:298 [inline]
inode_security security/selinux/hooks.c:332 [inline]
selinux_file_open+0xe4/0x330 security/selinux/hooks.c:4145
security_file_open+0x36/0x70 security/security.c:2636
do_dentry_open+0x216/0xa60 fs/open.c:939
vfs_open+0x37/0x1e0 fs/open.c:1094
dentry_open+0x4a/0x90 fs/open.c:1117
pidfs_alloc_file+0xe2/0x180 fs/pidfs.c:1079
pidfd_prepare+0x11d/0x170 kernel/fork.c:1900
pidfd_create kernel/pid.c:625 [inline]
__do_sys_pidfd_open kernel/pid.c:661 [inline]
__se_sys_pidfd_open+0x133/0x270 kernel/pid.c:646
__x64_sys_pidfd_open+0x31/0x40 kernel/pid.c:646
x64_sys_call+0x57c/0x3000 arch/x86/include/generated/asm/syscalls_64.h:435
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xca/0x2b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4632 Comm: syz.7.319 Not tainted syzkaller #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
==================================================================


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