EXT4-fs (loop6): Cannot turn on quotas: error -117
EXT4-fs error (device loop6): ext4_validate_block_bitmap:441: comm syz.6.8156: bg 0: block 40: padding at end of block bitmap is not set
==================================================================
BUG: KCSAN: data-race in _prb_read_valid / prb_reserve

write to 0xffffffff868bd400 of 88 bytes by task 27807 on cpu 1:
 prb_reserve+0x696/0xaf0 kernel/printk/printk_ringbuffer.c:1635
 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2326
 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
 tproxy_tg4_check+0xf6/0x100 net/netfilter/xt_TPROXY.c:202
 xt_check_target+0x28a/0x4c0 net/netfilter/x_tables.c:1038
 check_target net/ipv4/netfilter/ip_tables.c:510 [inline]
 find_check_entry net/ipv4/netfilter/ip_tables.c:552 [inline]
 translate_table+0xc31/0xf90 net/ipv4/netfilter/ip_tables.c:716
 do_replace net/ipv4/netfilter/ip_tables.c:1137 [inline]
 do_ipt_set_ctl+0x66f/0x820 net/ipv4/netfilter/ip_tables.c:1635
 nf_setsockopt+0x196/0x1b0 net/netfilter/nf_sockopt.c:101
 ip_setsockopt+0x102/0x110 net/ipv4/ip_sockglue.c:1424
 ipv6_setsockopt+0xfb/0x130 net/ipv6/ipv6_sockglue.c:988
 dccp_setsockopt+0xe4/0x660 net/dccp/proto.c:579
 sock_common_setsockopt+0x66/0x80 net/core/sock.c:3894
 do_sock_setsockopt net/socket.c:2296 [inline]
 __sys_setsockopt+0x181/0x200 net/socket.c:2321
 __do_sys_setsockopt net/socket.c:2327 [inline]
 __se_sys_setsockopt net/socket.c:2324 [inline]
 __x64_sys_setsockopt+0x64/0x80 net/socket.c:2324
 x64_sys_call+0x2bd5/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:55
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff868bd400 of 8 bytes by task 27798 on cpu 0:
 desc_read kernel/printk/printk_ringbuffer.c:486 [inline]
 prb_first_seq kernel/printk/printk_ringbuffer.c:1957 [inline]
 _prb_read_valid+0x383/0x920 kernel/printk/printk_ringbuffer.c:2114
 prb_read_valid+0x3c/0x60 kernel/printk/printk_ringbuffer.c:2185
 printk_get_next_message+0xc8/0x510 kernel/printk/printk.c:3005
 console_emit_next_record kernel/printk/printk.c:3092 [inline]
 console_flush_all+0x290/0x730 kernel/printk/printk.c:3226
 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
 console_unlock+0xa1/0x330 kernel/printk/printk.c:3325
 vprintk_emit+0x388/0x650 kernel/printk/printk.c:2450
 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+0x248/0x320 fs/ext4/super.c:817
 ext4_validate_block_bitmap+0x557/0x5a0 fs/ext4/balloc.c:-1
 ext4_wait_block_bitmap+0xda/0x150 fs/ext4/balloc.c:591
 ext4_mb_init_cache+0x2f1/0xb60 fs/ext4/mballoc.c:1352
 ext4_mb_init_group+0x223/0x3b0 fs/ext4/mballoc.c:1543
 ext4_mb_load_buddy_gfp+0x6ed/0x750 fs/ext4/mballoc.c:1613
 ext4_mb_clear_bb fs/ext4/mballoc.c:6449 [inline]
 ext4_free_blocks+0x758/0x1400 fs/ext4/mballoc.c:6651
 ext4_remove_blocks fs/ext4/extents.c:2547 [inline]
 ext4_ext_rm_leaf fs/ext4/extents.c:2712 [inline]
 ext4_ext_remove_space+0x1775/0x2900 fs/ext4/extents.c:2961
 ext4_ext_truncate+0xc7/0x170 fs/ext4/extents.c:4466
 ext4_truncate+0x6f8/0xac0 fs/ext4/inode.c:4232
 ext4_process_orphan+0x110/0x1c0 fs/ext4/orphan.c:339
 ext4_orphan_cleanup+0x6a8/0xa00 fs/ext4/orphan.c:474
 __ext4_fill_super fs/ext4/super.c:5607 [inline]
 ext4_fill_super+0x3171/0x34e0 fs/ext4/super.c:5726
 get_tree_bdev_flags+0x28e/0x300 fs/super.c:1636
 get_tree_bdev+0x1f/0x30 fs/super.c:1659
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5758
 vfs_get_tree+0x54/0x1d0 fs/super.c:1759
 do_new_mount+0x207/0x680 fs/namespace.c:3884
 path_mount+0x4a4/0xb20 fs/namespace.c:4211
 do_mount fs/namespace.c:4224 [inline]
 __do_sys_mount fs/namespace.c:4435 [inline]
 __se_sys_mount+0x28f/0x2e0 fs/namespace.c:4412
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4412
 x64_sys_call+0xd36/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000000026d8 -> 0x00000000000046d8

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 27798 Comm: syz.6.8156 Not tainted 6.15.0-rc5-syzkaller-00123-g2c89c1b655c0 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
==================================================================
EXT4-fs error (device loop6) in ext4_mb_clear_bb:6548: Corrupt filesystem
EXT4-fs (loop6): 1 truncate cleaned up
EXT4-fs (loop6): mounted filesystem 00000000-0000-0000-0000-000000000000 ro without journal. Quota mode: writeback.