EXT4-fs error (device loop0): ext4_do_update_inode:5568: inode #3: comm syz.0.3874: corrupted inode contents EXT4-fs error (device loop0): __ext4_ext_dirty:206: inode #3: comm syz.0.3874: mark_inode_dirty error ================================================================== BUG: KCSAN: data-race in data_push_tail / vsnprintf write to 0xffffffff88e3f2e8 of 24 bytes by task 28006 on cpu 1: vsnprintf+0x2ce/0x890 lib/vsprintf.c:2826 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 ext4_do_update_inode fs/ext4/inode.c:5568 [inline] ext4_mark_iloc_dirty+0x35e/0xda0 fs/ext4/inode.c:6224 __ext4_mark_inode_dirty+0x2e2/0x3f0 fs/ext4/inode.c:6430 ext4_dirty_inode+0x92/0xc0 fs/ext4/inode.c:6459 __mark_inode_dirty+0x15c/0x760 fs/fs-writeback.c:2527 ext4_mb_new_blocks+0x10b9/0x2050 fs/ext4/mballoc.c:-1 ext4_ext_map_blocks+0xff5/0x38a0 fs/ext4/extents.c:4383 ext4_map_create_blocks fs/ext4/inode.c:609 [inline] ext4_map_blocks+0x61c/0xd70 fs/ext4/inode.c:813 ext4_getblk+0x114/0x510 fs/ext4/inode.c:960 ext4_bread+0x28/0x110 fs/ext4/inode.c:1023 ext4_quota_write+0x167/0x360 fs/ext4/super.c:7297 write_blk fs/quota/quota_tree.c:70 [inline] get_free_dqblk+0x20b/0x340 fs/quota/quota_tree.c:136 do_insert_tree+0x19a/0x9b0 fs/quota/quota_tree.c:347 do_insert_tree+0x753/0x9b0 fs/quota/quota_tree.c:402 do_insert_tree+0x753/0x9b0 fs/quota/quota_tree.c:402 do_insert_tree+0x753/0x9b0 fs/quota/quota_tree.c:402 dq_insert_tree fs/quota/quota_tree.c:432 [inline] qtree_write_dquot+0x2cb/0x300 fs/quota/quota_tree.c:451 v2_write_dquot+0xda/0x140 fs/quota/quota_v2.c:372 dquot_acquire+0x1c3/0x2b0 fs/quota/dquot.c:470 ext4_acquire_dquot+0x15f/0x200 fs/ext4/super.c:6929 dqget+0x535/0x8d0 fs/quota/dquot.c:977 __dquot_initialize+0x27f/0x7c0 fs/quota/dquot.c:1505 dquot_initialize+0x1a/0x30 fs/quota/dquot.c:1567 ext4_process_orphan+0x32/0x1c0 fs/ext4/orphan.c:329 ext4_orphan_cleanup+0x6a8/0xa00 fs/ext4/orphan.c:474 __ext4_fill_super fs/ext4/super.c:5605 [inline] ext4_fill_super+0x3171/0x34e0 fs/ext4/super.c:5724 get_tree_bdev_flags+0x291/0x300 fs/super.c:1681 get_tree_bdev+0x1f/0x30 fs/super.c:1704 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5756 vfs_get_tree+0x54/0x1d0 fs/super.c:1804 do_new_mount+0x207/0x680 fs/namespace.c:3902 path_mount+0x4a4/0xb20 fs/namespace.c:4226 do_mount fs/namespace.c:4239 [inline] __do_sys_mount fs/namespace.c:4450 [inline] __se_sys_mount+0x28f/0x2e0 fs/namespace.c:4427 __x64_sys_mount+0x67/0x80 fs/namespace.c:4427 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+0xd2/0x200 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffffffff88e3f2f8 of 8 bytes by task 28005 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_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 __ext4_mark_inode_dirty+0xbd/0x3f0 fs/ext4/inode.c:6433 __ext4_ext_dirty+0xdb/0x1f0 fs/ext4/extents.c:206 ext4_ext_insert_extent+0x13db/0x29b0 fs/ext4/extents.c:2192 ext4_ext_map_blocks+0x10b8/0x38a0 fs/ext4/extents.c:4404 ext4_map_create_blocks fs/ext4/inode.c:609 [inline] ext4_map_blocks+0x61c/0xd70 fs/ext4/inode.c:813 ext4_getblk+0x114/0x510 fs/ext4/inode.c:960 ext4_bread+0x28/0x110 fs/ext4/inode.c:1023 ext4_quota_write+0x167/0x360 fs/ext4/super.c:7297 write_blk fs/quota/quota_tree.c:70 [inline] get_free_dqblk+0x20b/0x340 fs/quota/quota_tree.c:136 do_insert_tree+0x19a/0x9b0 fs/quota/quota_tree.c:347 do_insert_tree+0x753/0x9b0 fs/quota/quota_tree.c:402 do_insert_tree+0x753/0x9b0 fs/quota/quota_tree.c:402 do_insert_tree+0x753/0x9b0 fs/quota/quota_tree.c:402 dq_insert_tree fs/quota/quota_tree.c:432 [inline] qtree_write_dquot+0x2cb/0x300 fs/quota/quota_tree.c:451 v2_write_dquot+0xda/0x140 fs/quota/quota_v2.c:372 dquot_acquire+0x1c3/0x2b0 fs/quota/dquot.c:470 ext4_acquire_dquot+0x15f/0x200 fs/ext4/super.c:6929 dqget+0x535/0x8d0 fs/quota/dquot.c:977 __dquot_initialize+0x27f/0x7c0 fs/quota/dquot.c:1505 dquot_initialize+0x1a/0x30 fs/quota/dquot.c:1567 ext4_process_orphan+0x32/0x1c0 fs/ext4/orphan.c:329 ext4_orphan_cleanup+0x6a8/0xa00 fs/ext4/orphan.c:474 __ext4_fill_super fs/ext4/super.c:5605 [inline] ext4_fill_super+0x3171/0x34e0 fs/ext4/super.c:5724 get_tree_bdev_flags+0x291/0x300 fs/super.c:1681 get_tree_bdev+0x1f/0x30 fs/super.c:1704 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5756 vfs_get_tree+0x54/0x1d0 fs/super.c:1804 do_new_mount+0x207/0x680 fs/namespace.c:3902 path_mount+0x4a4/0xb20 fs/namespace.c:4226 do_mount fs/namespace.c:4239 [inline] __do_sys_mount fs/namespace.c:4450 [inline] __se_sys_mount+0x28f/0x2e0 fs/namespace.c:4427 __x64_sys_mount+0x67/0x80 fs/namespace.c:4427 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+0xd2/0x200 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x00000000fffffd8b -> 0x6f6c206563697665 Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 28005 Comm: syz.0.3874 Not tainted 6.16.0-rc7-syzkaller-00127-g302f88ff3584 #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 ================================================================== EXT4-fs error (device loop0): ext4_acquire_dquot:6933: comm syz.0.3874: Failed to acquire dquot type 0 EXT4-fs error (device loop0): ext4_do_update_inode:5568: inode #16: comm syz.0.3874: corrupted inode contents EXT4-fs error (device loop0): ext4_dirty_inode:6459: inode #16: comm syz.0.3874: mark_inode_dirty error EXT4-fs error (device loop0): ext4_do_update_inode:5568: inode #16: comm syz.0.3874: corrupted inode contents EXT4-fs error (device loop0): __ext4_ext_dirty:206: inode #16: comm syz.0.3874: mark_inode_dirty error EXT4-fs error (device loop0): ext4_do_update_inode:5568: inode #16: comm syz.0.3874: corrupted inode contents EXT4-fs error (device loop0) in ext4_orphan_del:305: Corrupt filesystem EXT4-fs error (device loop0): ext4_do_update_inode:5568: inode #16: comm syz.0.3874: corrupted inode contents EXT4-fs error (device loop0): ext4_truncate:4597: inode #16: comm syz.0.3874: mark_inode_dirty error EXT4-fs error (device loop0) in ext4_process_orphan:347: Corrupt filesystem EXT4-fs (loop0): 1 truncate cleaned up EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback. ext4 filesystem being mounted at /160/file0 supports timestamps until 2038-01-19 (0x7fffffff)