[moderation] [selinux?] KCSAN: data-race in inode_doinit_with_dentry / inode_doinit_with_dentry (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 977b1ef51866 Merge tag 'block-6.9-20240420' of git://git.k..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=176de227180000
kernel config: https://syzkaller.appspot.com/x/.config?x=eaea34ec4c9b6fb6
dashboard link: https://syzkaller.appspot.com/bug?extid=a3402bb464b92bd64136
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
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/deeaf44a7761/disk-977b1ef5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/befb9e8ca501/vmlinux-977b1ef5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/558e81cc1437/bzImage-977b1ef5.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a3402b...@syzkaller.appspotmail.com

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

write to 0xffff88811743a112 of 1 bytes by task 15552 on cpu 1:
inode_doinit_with_dentry+0x29c/0x840 security/selinux/hooks.c:1443
__inode_security_revalidate security/selinux/hooks.c:295 [inline]
inode_security security/selinux/hooks.c:320 [inline]
selinux_file_open+0x101/0x3b0 security/selinux/hooks.c:3968
security_file_open+0x3a/0x70 security/security.c:2961
do_dentry_open+0x221/0xbe0 fs/open.c:942
vfs_open fs/open.c:1089 [inline]
dentry_open+0x7e/0xc0 fs/open.c:1103
pidfs_alloc_file+0xe6/0x150 fs/pidfs.c:273
__pidfd_prepare kernel/fork.c:2029 [inline]
pidfd_prepare+0x5f/0xe0 kernel/fork.c:2077
pidfd_create kernel/pid.c:608 [inline]
__do_sys_pidfd_open kernel/pid.c:644 [inline]
__se_sys_pidfd_open+0x123/0x240 kernel/pid.c:629
__x64_sys_pidfd_open+0x31/0x40 kernel/pid.c:629
x64_sys_call+0x28a7/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:435
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+0x77/0x7f

read to 0xffff88811743a112 of 1 bytes by task 15553 on cpu 0:
inode_doinit_with_dentry+0x78/0x840 security/selinux/hooks.c:1418
__inode_security_revalidate security/selinux/hooks.c:295 [inline]
inode_security security/selinux/hooks.c:320 [inline]
selinux_file_open+0x101/0x3b0 security/selinux/hooks.c:3968
security_file_open+0x3a/0x70 security/security.c:2961
do_dentry_open+0x221/0xbe0 fs/open.c:942
vfs_open fs/open.c:1089 [inline]
dentry_open+0x7e/0xc0 fs/open.c:1103
pidfs_alloc_file+0xe6/0x150 fs/pidfs.c:273
__pidfd_prepare kernel/fork.c:2029 [inline]
pidfd_prepare+0x5f/0xe0 kernel/fork.c:2077
pidfd_create kernel/pid.c:608 [inline]
__do_sys_pidfd_open kernel/pid.c:644 [inline]
__se_sys_pidfd_open+0x123/0x240 kernel/pid.c:629
__x64_sys_pidfd_open+0x31/0x40 kernel/pid.c:629
x64_sys_call+0x28a7/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:435
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+0x77/0x7f

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 15553 Comm: syz-executor.3 Not tainted 6.9.0-rc4-syzkaller-00266-g977b1ef51866 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
==================================================================


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