loop0: detected capacity change from 0 to 1024 EXT4-fs: inline encryption not supported EXT4-fs: Ignoring removed nomblk_io_submit option EXT4-fs: Ignoring removed bh option ext4: Unknown parameter ' Z* m.Dc8'@C9G9?9S{1Jլ5 æԌqqY糔' EXT4-fs error (device loop0): ext4_mb_mark_diskspace_used:4193: comm syz.0.9140: Allocating blocks 497-513 which overlap fs metadata ================================================================== BUG: KCSAN: data-race in _prb_read_valid / data_alloc write to 0xffffffff86890588 of 8 bytes by task 29210 on cpu 1: data_alloc+0x274/0x2e0 kernel/printk/printk_ringbuffer.c:1101 prb_reserve+0x807/0xaf0 kernel/printk/printk_ringbuffer.c:1685 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2299 vprintk_emit+0x10d/0x580 kernel/printk/printk.c:2399 vprintk_default+0x26/0x30 kernel/printk/printk.c:2438 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2448 set_capacity_and_notify+0x14c/0x1f0 block/genhd.c:93 loop_set_size+0x2e/0x70 drivers/block/loop.c:220 loop_configure+0x828/0x9c0 drivers/block/loop.c:1081 lo_ioctl+0x1e1/0x12b0 drivers/block/loop.c:1536 blkdev_ioctl+0x356/0x440 block/ioctl.c:705 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583 x64_sys_call+0x1816/0x3000 arch/x86/include/generated/asm/syscalls_64.h:17 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 0xffffffff86890588 of 16 bytes by task 29202 on cpu 0: desc_read kernel/printk/printk_ringbuffer.c:479 [inline] desc_read_finalized_seq kernel/printk/printk_ringbuffer.c:1892 [inline] prb_read kernel/printk/printk_ringbuffer.c:1940 [inline] _prb_read_valid+0x1bc/0x920 kernel/printk/printk_ringbuffer.c:2131 prb_read_valid+0x3c/0x60 kernel/printk/printk_ringbuffer.c:2203 __console_flush_and_unlock kernel/printk/printk.c:3277 [inline] console_unlock+0x164/0x2e0 kernel/printk/printk.c:3298 vprintk_emit+0x3b5/0x580 kernel/printk/printk.c:2423 vprintk_default+0x26/0x30 kernel/printk/printk.c:2438 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2448 __ext4_error+0x248/0x320 fs/ext4/super.c:822 ext4_mb_mark_diskspace_used+0x273/0x3c0 fs/ext4/mballoc.c:4192 ext4_mb_new_blocks+0xa62/0x2080 fs/ext4/mballoc.c:6313 ext4_ext_map_blocks+0xff5/0x38a0 fs/ext4/extents.c:4383 ext4_map_create_blocks fs/ext4/inode.c:609 [inline] ext4_map_blocks+0x5ee/0xd00 fs/ext4/inode.c:811 ext4_alloc_file_blocks+0x2a9/0x800 fs/ext4/extents.c:4551 ext4_do_fallocate+0x13b/0x3f0 fs/ext4/extents.c:4742 ext4_fallocate+0x20d/0x2f0 fs/ext4/extents.c:4805 vfs_fallocate+0x3b6/0x400 fs/open.c:342 ksys_fallocate fs/open.c:366 [inline] __do_sys_fallocate fs/open.c:371 [inline] __se_sys_fallocate fs/open.c:369 [inline] __x64_sys_fallocate+0x7a/0xd0 fs/open.c:369 x64_sys_call+0x2518/0x3000 arch/x86/include/generated/asm/syscalls_64.h:286 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 Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 29202 Comm: syz.0.9140 Tainted: G W syzkaller #0 PREEMPT(voluntary) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 ================================================================== EXT4-fs (loop0): pa ffff8881069dae70: logic 16, phys. 145, len 23 EXT4-fs error (device loop0): ext4_mb_release_inode_pa:5444: group 0, free 0, pa_free 1