EXT4-fs error (device loop3): ext4_ext_check_inode:520: inode #2: comm syz-executor.3: pblk 0 bad header/extent: invalid extent entries - magic f30a, entries 1, max 4(4), depth 0(0)
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BUG: KCSAN: data-race in data_push_tail / vsnprintf

write to 0xffffffff86eda4d7 of 1 bytes by task 7869 on cpu 0:
 vsnprintf+0xdd0/0xe20
 va_format lib/vsprintf.c:1683 [inline]
 pointer+0x8a1/0xd10 lib/vsprintf.c:2450
 vsnprintf+0x861/0xe20 lib/vsprintf.c:2823
 vscnprintf+0x42/0x80 lib/vsprintf.c:2925
 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2124
 vprintk_store+0x56f/0x800 kernel/printk/printk.c:2238
 vprintk_emit+0xd0/0x5d0 kernel/printk/printk.c:2284
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2318
 vprintk+0x71/0x80 kernel/printk/printk_safe.c:45
 _printk+0x7a/0xa0 kernel/printk/printk.c:2328
 __ext4_msg+0x18a/0x1a0 fs/ext4/super.c:1006
 __ext4_fill_super fs/ext4/super.c:5644 [inline]
 ext4_fill_super+0x3111/0x39a0 fs/ext4/super.c:5712
 get_tree_bdev+0x272/0x300 fs/super.c:1598
 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5744
 vfs_get_tree+0x51/0x1b0 fs/super.c:1771
 do_new_mount+0x203/0x660 fs/namespace.c:3337
 path_mount+0x496/0xb30 fs/namespace.c:3664
 do_mount fs/namespace.c:3677 [inline]
 __do_sys_mount fs/namespace.c:3886 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3863
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3863
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffffffff86eda4d0 of 8 bytes by task 7871 on cpu 1:
 data_make_reusable kernel/printk/printk_ringbuffer.c:590 [inline]
 data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:675
 data_alloc+0xbe/0x2c0 kernel/printk/printk_ringbuffer.c:1046
 prb_reserve+0x893/0xbc0 kernel/printk/printk_ringbuffer.c:1555
 vprintk_store+0x53e/0x800 kernel/printk/printk.c:2228
 vprintk_emit+0xd0/0x5d0 kernel/printk/printk.c:2284
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2318
 vprintk+0x71/0x80 kernel/printk/printk_safe.c:45
 _printk+0x7a/0xa0 kernel/printk/printk.c:2328
 __ext4_error_inode+0x2d5/0x400 fs/ext4/super.c:869
 __ext4_ext_check+0x4c5/0x870 fs/ext4/extents.c:504
 ext4_ext_check_inode+0x46/0x50 fs/ext4/extents.c:520
 __ext4_iget+0x19ed/0x1e90 fs/ext4/inode.c:4934
 __ext4_fill_super fs/ext4/super.c:5482 [inline]
 ext4_fill_super+0x2f71/0x39a0 fs/ext4/super.c:5712
 get_tree_bdev+0x272/0x300 fs/super.c:1598
 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5744
 vfs_get_tree+0x51/0x1b0 fs/super.c:1771
 do_new_mount+0x203/0x660 fs/namespace.c:3337
 path_mount+0x496/0xb30 fs/namespace.c:3664
 do_mount fs/namespace.c:3677 [inline]
 __do_sys_mount fs/namespace.c:3886 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3863
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3863
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x000000010000cf98 -> 0x0064656c69616620

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7871 Comm: syz-executor.3 Not tainted 6.7.0-rc6-syzkaller-00022-g55cb5f43689d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
==================================================================
EXT4-fs (loop3): get root inode failed
EXT4-fs (loop3): mount failed