erofs: (device loop2): mounted with root inode @ nid 36.
erofs: (device loop2): z_erofs_extent_lookback: bogus lookback distance @ nid 36
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 110905067 P4D 110905067 PUD 0 
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 375 Comm: syz.2.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0018:ffffc90000d96da8 EFLAGS: 00010246
RAX: 1ffffffff0a7c1ae RBX: ffffc90000d97700 RCX: ffff888110e593c0
RDX: 0000000000000000 RSI: ffffc90000d97700 RDI: ffffc90000d97260
RBP: ffffc90000d96dd0 R08: ffffc90000d9728f R09: ffffc90000d9728a
R10: dffffc0000000000 R11: fffff520001b2e52 R12: dffffc0000000000
R13: 000000000000073b R14: ffffc90000d97260 R15: ffffffff853e0d70
FS:  000055555d9ea500(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000110bb4000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 z_erofs_decompress+0x79/0xb0 fs/erofs/decompressor.c:360
 z_erofs_decompress_pcluster fs/erofs/zdata.c:1110 [inline]
 z_erofs_decompress_queue+0x10ff/0x1a90 fs/erofs/zdata.c:1188
 z_erofs_runqueue+0x11fe/0x1280 fs/erofs/zdata.c:-1
 z_erofs_readpage+0x225/0x500 fs/erofs/zdata.c:1533
 do_read_cache_page+0x69b/0xaa0 mm/filemap.c:-1
 read_cache_page+0x50/0x70 mm/filemap.c:3296
 read_mapping_page include/linux/pagemap.h:498 [inline]
 find_target_block_classic fs/erofs/namei.c:104 [inline]
 erofs_namei+0x162/0x10d0 fs/erofs/namei.c:184
 erofs_lookup+0xa5/0x260 fs/erofs/namei.c:228
 __lookup_slow+0x2b8/0x410 fs/namei.c:1648
 lookup_slow+0x57/0x70 fs/namei.c:1665
 walk_component+0x325/0x460 fs/namei.c:1960
 link_path_walk+0x5b2/0xba0 fs/namei.c:-1
 path_parentat fs/namei.c:2487 [inline]
 filename_parentat+0x200/0x5e0 fs/namei.c:2509
 filename_create+0xd4/0x680 fs/namei.c:3598
 user_path_create fs/namei.c:3673 [inline]
 do_mkdirat+0x5e/0x340 fs/namei.c:3813
 __do_sys_mkdir fs/namei.c:3836 [inline]
 __se_sys_mkdir fs/namei.c:3834 [inline]
 __x64_sys_mkdir+0x60/0x70 fs/namei.c:3834
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fbf667f1e59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdbb6b4918 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007fbf66a6afa0 RCX: 00007fbf667f1e59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000000
RBP: 00007fbf66887d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbf66a6afac R14: 00007fbf66a6afa0 R15: 00007fbf66a6afa0
Modules linked in:
CR2: 0000000000000000
---[ end trace fdc2c44565c2ce26 ]---
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0018:ffffc90000d96da8 EFLAGS: 00010246
RAX: 1ffffffff0a7c1ae RBX: ffffc90000d97700 RCX: ffff888110e593c0
RDX: 0000000000000000 RSI: ffffc90000d97700 RDI: ffffc90000d97260
RBP: ffffc90000d96dd0 R08: ffffc90000d9728f R09: ffffc90000d9728a
R10: dffffc0000000000 R11: fffff520001b2e52 R12: dffffc0000000000
R13: 000000000000073b R14: ffffc90000d97260 R15: ffffffff853e0d70
FS:  000055555d9ea500(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000110bb4000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400