syzbot

kauditd_printk_skb: 414 callbacks suppressed
==================================================================
BUG: KCSAN: data-race in data_push_tail / string

write to 0xffffffff88e4fee0 of 1 bytes by task 9101 on cpu 1:
 string_nocheck lib/vsprintf.c:643 [inline]
 string+0x187/0x220 lib/vsprintf.c:721
 vsnprintf+0x532/0x890 lib/vsprintf.c:2874
 vscnprintf+0x41/0x90 lib/vsprintf.c:2939
 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2216
 vprintk_store+0x599/0x860 kernel/printk/printk.c:2336
 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2475
 __ext4_error_inode+0x2ca/0x3f0 fs/ext4/super.c:844
 check_xattrs+0x25e/0x7d0 fs/ext4/xattr.c:289
 __ext4_xattr_check_block fs/ext4/xattr.c:303 [inline]
 ext4_xattr_block_get fs/ext4/xattr.c:593 [inline]
 ext4_xattr_get+0x1ed/0x470 fs/ext4/xattr.c:708
 ext4_xattr_security_get+0x32/0x40 fs/ext4/xattr_security.c:20
 __vfs_getxattr+0x2aa/0x2c0 fs/xattr.c:423
 inode_doinit_use_xattr+0x7a/0x2d0 security/selinux/hooks.c:1371
 inode_doinit_with_dentry+0x596/0x7a0 security/selinux/hooks.c:1496
 __inode_security_revalidate security/selinux/hooks.c:296 [inline]
 dentry_has_perm security/selinux/hooks.c:1699 [inline]
 selinux_inode_getxattr+0x102/0x210 security/selinux/hooks.c:3470
 security_inode_getxattr+0x7c/0xc0 security/security.c:2551
 vfs_getxattr+0x8c/0x250 fs/xattr.c:438
 do_getxattr+0x124/0x2a0 fs/xattr.c:787
 filename_getxattr+0xac/0x180 fs/xattr.c:817
 path_getxattrat fs/xattr.c:859 [inline]
 __do_sys_getxattr fs/xattr.c:891 [inline]
 __se_sys_getxattr fs/xattr.c:888 [inline]
 __x64_sys_getxattr+0x112/0x140 fs/xattr.c:888
 x64_sys_call+0x2f41/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:192
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff88e4fee0 of 8 bytes by task 29 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline]
 data_push_tail+0xfd/0x420 kernel/printk/printk_ringbuffer.c:679
 data_alloc+0xbf/0x2b0 kernel/printk/printk_ringbuffer.c:1054
 prb_reserve+0x808/0xaf0 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2326
 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426
 vprintk_deferred kernel/printk/printk.c:4602 [inline]
 _printk_deferred+0x82/0xb0 kernel/printk/printk.c:4611
 ___ratelimit+0x4b1/0x4f0 lib/ratelimit.c:86
 __printk_ratelimit+0x1c/0x30 kernel/printk/printk.c:4627
 kauditd_printk_skb kernel/audit.c:545 [inline]
 kauditd_hold_skb+0x63/0x1c0 kernel/audit.c:581
 kauditd_send_queue+0x273/0x2c0 kernel/audit.c:766
 kauditd_thread+0x421/0x630 kernel/audit.c:890
 kthread+0x489/0x510 kernel/kthread.c:464
 ret_from_fork+0xdd/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00000000ffffecfc -> 0x72747461785f3474

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 29 Comm: kauditd Not tainted 6.16.0-syzkaller-10910-g0905809b38bd #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
==================================================================
audit: type=1400 audit(1754137197.602:13413): avc:  denied  { read } for  pid=9100 comm="syz.4.1993" name="file1" dev="loop4" ino=15 scontext=root:sysadm_r:sysadm_t tcontext=system_u:object_r:unlabeled_t tclass=file permissive=1