EXT4-fs error (device loop0): ext4_map_blocks:617: inode #16: block 42: comm syz.0.23: lblock 1 mapped to illegal pblock 42 (length 1) EXT4-fs (loop0): Remounting filesystem read-only ------------[ cut here ]------------ kernel BUG at fs/ext4/ext4.h:2984! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 443 Comm: syz.0.23 Not tainted 5.4.289-syzkaller-00025-g49530c73f82d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:ext4_get_group_info fs/ext4/ext4.h:2984 [inline] RIP: 0010:ext4_mb_load_buddy_gfp+0xf29/0xf40 fs/ext4/mballoc.c:1117 Code: ff e8 cb a1 c9 ff e9 0a f3 ff ff 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 52 f3 ff ff e8 d1 a1 c9 ff e9 48 f3 ff ff e8 37 b7 99 ff <0f> 0b e8 30 b7 99 ff 0f 0b e8 29 b7 99 ff 0f 0b e8 22 b7 99 ff 0f RSP: 0018:ffff8881e910fbc8 EFLAGS: 00010283 RAX: ffffffff81ca9339 RBX: 0000000000000001 RCX: 0000000000080000 RDX: ffffc90000940000 RSI: 0000000000000929 RDI: 000000000000092a RBP: ffff8881e9028000 R08: ffffffff81ca84e2 R09: ffffed103ba51f2d R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff1103d205a7e R13: dffffc0000000000 R14: 000000001f337701 R15: ffff8881e902d3f0 FS: 00007f9a7eb8d6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31c1fffc CR3: 00000001ea76a000 CR4: 00000000003406a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ext4_discard_preallocations+0x603/0xb90 fs/ext4/mballoc.c:4124 ext4_punch_hole+0x5f0/0xad0 fs/ext4/inode.c:4482 ext4_fallocate+0x265/0x570 fs/ext4/extents.c:4949 vfs_fallocate+0x551/0x6b0 fs/open.c:309 ksys_fallocate fs/open.c:332 [inline] __do_sys_fallocate fs/open.c:340 [inline] __se_sys_fallocate fs/open.c:338 [inline] __x64_sys_fallocate+0xb9/0x100 fs/open.c:338 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 RIP: 0033:0x7f9a80522d29 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9a7eb8d038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f9a8073bfa0 RCX: 00007f9a80522d29 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000004 RBP: 00007f9a805a42a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000001a00 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9a8073bfa0 R15: 00007fff4474a168 Modules linked in: ---[ end trace fdb7623080b4cb0c ]--- RIP: 0010:ext4_get_group_info fs/ext4/ext4.h:2984 [inline] RIP: 0010:ext4_mb_load_buddy_gfp+0xf29/0xf40 fs/ext4/mballoc.c:1117 Code: ff e8 cb a1 c9 ff e9 0a f3 ff ff 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 52 f3 ff ff e8 d1 a1 c9 ff e9 48 f3 ff ff e8 37 b7 99 ff <0f> 0b e8 30 b7 99 ff 0f 0b e8 29 b7 99 ff 0f 0b e8 22 b7 99 ff 0f RSP: 0018:ffff8881e910fbc8 EFLAGS: 00010283 RAX: ffffffff81ca9339 RBX: 0000000000000001 RCX: 0000000000080000 RDX: ffffc90000940000 RSI: 0000000000000929 RDI: 000000000000092a RBP: ffff8881e9028000 R08: ffffffff81ca84e2 R09: ffffed103ba51f2d R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff1103d205a7e R13: dffffc0000000000 R14: 000000001f337701 R15: ffff8881e902d3f0 FS: 00007f9a7eb8d6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd631cdd178 CR3: 00000001ea76a000 CR4: 00000000003406b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400