EXT4-fs (loop8): Remounting filesystem read-only EXT4-fs error (device loop8): ext4_do_update_inode:5270: inode #3: comm syz.8.13046: corrupted inode contents EXT4-fs (loop8): Remounting filesystem read-only EXT4-fs error (device loop8): __ext4_ext_dirty:206: inode #3: comm syz.8.13046: mark_inode_dirty error EXT4-fs (loop8): Remounting filesystem read-only BUG: unable to handle page fault for address: ffffffffffffff93 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 7012067 P4D 7012067 PUD 7014067 PMD 0 Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 9363 Comm: syz.8.13046 Tainted: G W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:ext4_ext_drop_refs fs/ext4/extents.c:119 [inline] RIP: 0010:ext4_free_ext_path fs/ext4/extents.c:128 [inline] RIP: 0010:ext4_ext_map_blocks+0x2e59/0x6200 fs/ext4/extents.c:4497 Code: 40 01 00 00 4d 85 f6 0f 84 bc 00 00 00 48 89 5c 24 20 49 8d 7e 08 48 89 f8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 38 16 00 00 <41> 0f b7 46 08 c1 e0 04 48 8d 04 40 48 89 44 24 08 49 8d 46 28 48 RSP: 0018:ffffc9000349e9a0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000080000 RDX: ffffc90000e89000 RSI: 000000000007ffff RDI: ffffffffffffff93 RBP: ffffc9000349ec50 R08: ffff888157a98063 R09: 1ffff1102af5300c R10: dffffc0000000000 R11: ffffed102af5300d R12: dffffc0000000000 R13: 1ffff92000693d60 R14: ffffffffffffff8b R15: 0000000000000001 FS: 00007fd8ec22c6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffff93 CR3: 0000000112ce5000 CR4: 00000000003506a0 Call Trace: ext4_map_blocks+0x9d8/0x1b70 fs/ext4/inode.c:679 ext4_getblk+0x1cc/0x6e0 fs/ext4/inode.c:890 ext4_bread+0x2b/0x170 fs/ext4/inode.c:946 ext4_quota_write+0x236/0x560 fs/ext4/super.c:7209 write_blk fs/quota/quota_tree.c:70 [inline] get_free_dqblk+0x34d/0x680 fs/quota/quota_tree.c:136 do_insert_tree+0x238/0x1060 fs/quota/quota_tree.c:347 do_insert_tree+0xa3f/0x1060 fs/quota/quota_tree.c:402 do_insert_tree+0xa3f/0x1060 fs/quota/quota_tree.c:402 do_insert_tree+0xa3f/0x1060 fs/quota/quota_tree.c:402 dq_insert_tree fs/quota/quota_tree.c:432 [inline] qtree_write_dquot+0x4b6/0x5e0 fs/quota/quota_tree.c:451 v2_write_dquot+0x130/0x1a0 fs/quota/quota_v2.c:361 dquot_acquire+0x30c/0x560 fs/quota/dquot.c:472 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6818 dqget+0xad0/0xf60 fs/quota/dquot.c:988 __dquot_initialize+0x3d4/0xc40 fs/quota/dquot.c:1517 dquot_initialize+0x1a/0x20 fs/quota/dquot.c:1579 ext4_process_orphan+0x59/0x320 fs/ext4/orphan.c:327 ext4_orphan_cleanup+0xb1a/0x1220 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5543 [inline] ext4_fill_super+0x7050/0x7590 fs/ext4/super.c:5674 get_tree_bdev+0x447/0x690 fs/super.c:1371 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5704 vfs_get_tree+0x9a/0x270 fs/super.c:1578 do_new_mount+0x251/0xb30 fs/namespace.c:3081 path_mount+0x659/0xfc0 fs/namespace.c:3411 do_mount fs/namespace.c:3424 [inline] __do_sys_mount fs/namespace.c:3632 [inline] __se_sys_mount+0x320/0x390 fs/namespace.c:3609 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3609 x64_sys_call+0x65d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd8eb39e0ca Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd8ec22be58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fd8ec22bee0 RCX: 00007fd8eb39e0ca RDX: 0000200000000340 RSI: 0000200000000980 RDI: 00007fd8ec22bea0 RBP: 0000200000000340 R08: 00007fd8ec22bee0 R09: 0000000000008000 R10: 0000000000008000 R11: 0000000000000246 R12: 0000200000000980 R13: 00007fd8ec22bea0 R14: 0000000000000519 R15: 000000000000002c Modules linked in: CR2: ffffffffffffff93 ---[ end trace 0000000000000000 ]--- RIP: 0010:ext4_ext_drop_refs fs/ext4/extents.c:119 [inline] RIP: 0010:ext4_free_ext_path fs/ext4/extents.c:128 [inline] RIP: 0010:ext4_ext_map_blocks+0x2e59/0x6200 fs/ext4/extents.c:4497 Code: 40 01 00 00 4d 85 f6 0f 84 bc 00 00 00 48 89 5c 24 20 49 8d 7e 08 48 89 f8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 38 16 00 00 <41> 0f b7 46 08 c1 e0 04 48 8d 04 40 48 89 44 24 08 49 8d 46 28 48 RSP: 0018:ffffc9000349e9a0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000080000 RDX: ffffc90000e89000 RSI: 000000000007ffff RDI: ffffffffffffff93 RBP: ffffc9000349ec50 R08: ffff888157a98063 R09: 1ffff1102af5300c R10: dffffc0000000000 R11: ffffed102af5300d R12: dffffc0000000000 R13: 1ffff92000693d60 R14: ffffffffffffff8b R15: 0000000000000001 FS: 00007fd8ec22c6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffff93 CR3: 0000000112ce5000 CR4: 00000000003506a0 ---------------- Code disassembly (best guess): 0: 40 01 00 rex add %eax,(%rax) 3: 00 4d 85 add %cl,-0x7b(%rbp) 6: f6 0f 84 testb $0x84,(%rdi) 9: bc 00 00 00 48 mov $0x48000000,%esp e: 89 5c 24 20 mov %ebx,0x20(%rsp) 12: 49 8d 7e 08 lea 0x8(%r14),%rdi 16: 48 89 f8 mov %rdi,%rax 19: 48 c1 e8 03 shr $0x3,%rax 1d: 42 0f b6 04 20 movzbl (%rax,%r12,1),%eax 22: 84 c0 test %al,%al 24: 0f 85 38 16 00 00 jne 0x1662 * 2a: 41 0f b7 46 08 movzwl 0x8(%r14),%eax <-- trapping instruction 2f: c1 e0 04 shl $0x4,%eax 32: 48 8d 04 40 lea (%rax,%rax,2),%rax 36: 48 89 44 24 08 mov %rax,0x8(%rsp) 3b: 49 8d 46 28 lea 0x28(%r14),%rax 3f: 48 rex.W