loop2: detected capacity change from 0 to 512 EXT4-fs (loop2): revision level too high, forcing read-only mode [EXT4 FS bs=1024, gc=1, bpg=8192, ipg=32, mo=8842c01c, mo2=0002] BUG: kernel NULL pointer dereference, address: 0000000000000011 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 58544067 P4D 58544067 PUD 61d96067 PMD 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 2 PID: 8653 Comm: syz-executor.2 Not tainted 6.10.0-rc2-syzkaller-00064-g71d7b52cc33b #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:___slab_alloc+0x27a/0x1870 mm/slub.c:3609 Code: 0b 49 83 7f 28 00 0f 85 de 07 00 00 4d 89 77 28 49 83 7c 24 10 00 0f 85 45 06 00 00 4d 8b 7c 24 18 4d 85 ff 0f 84 d2 06 00 00 <49> 8b 47 10 83 bd 68 ff ff ff ff 49 89 44 24 18 74 20 49 8b 07 48 RSP: 0018:ffffc90004fbf820 EFLAGS: 00010002 RAX: 0000000000000000 RBX: 0000000000000202 RCX: ffffffff816bc84e RDX: 0000000000000001 RSI: ffffffff81e1a018 RDI: 0000000000000000 RBP: ffffc90004fbf900 R08: 0000000000000000 R09: fffffbfff283f058 R10: ffffffff941f82c7 R11: 0000000000000001 R12: ffffe8ffad26aba0 R13: ffff888019157680 R14: ffff88801bfd0000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff88802c200000(0063) knlGS:00000000f5f30b40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 0000000000000011 CR3: 00000000632a8000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3756 __slab_alloc_node mm/slub.c:3809 [inline] slab_alloc_node mm/slub.c:3988 [inline] kmem_cache_alloc_noprof+0x2ae/0x2f0 mm/slub.c:4007 ext4_mb_add_groupinfo+0x445/0x1180 fs/ext4/mballoc.c:3355 ext4_mb_init_backend fs/ext4/mballoc.c:3434 [inline] ext4_mb_init+0x127a/0x2530 fs/ext4/mballoc.c:3732 __ext4_fill_super fs/ext4/super.c:5501 [inline] ext4_fill_super+0x6d55/0xacf0 fs/ext4/super.c:5676 get_tree_bdev+0x36f/0x610 fs/super.c:1615 vfs_get_tree+0x8f/0x380 fs/super.c:1780 do_new_mount fs/namespace.c:3352 [inline] path_mount+0x6e1/0x1f10 fs/namespace.c:3679 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount fs/namespace.c:3875 [inline] __ia32_sys_mount+0x295/0x320 fs/namespace.c:3875 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf733e579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f5f30400 EFLAGS: 00000292 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00000000f5f30460 RCX: 0000000020000380 RDX: 0000000020000040 RSI: 0000000022000011 RDI: 00000000f5f304a0 RBP: 00000000f5f30460 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: CR2: 0000000000000011 ---[ end trace 0000000000000000 ]--- RIP: 0010:___slab_alloc+0x27a/0x1870 mm/slub.c:3609 Code: 0b 49 83 7f 28 00 0f 85 de 07 00 00 4d 89 77 28 49 83 7c 24 10 00 0f 85 45 06 00 00 4d 8b 7c 24 18 4d 85 ff 0f 84 d2 06 00 00 <49> 8b 47 10 83 bd 68 ff ff ff ff 49 89 44 24 18 74 20 49 8b 07 48 RSP: 0018:ffffc90004fbf820 EFLAGS: 00010002 RAX: 0000000000000000 RBX: 0000000000000202 RCX: ffffffff816bc84e RDX: 0000000000000001 RSI: ffffffff81e1a018 RDI: 0000000000000000 RBP: ffffc90004fbf900 R08: 0000000000000000 R09: fffffbfff283f058 R10: ffffffff941f82c7 R11: 0000000000000001 R12: ffffe8ffad26aba0 R13: ffff888019157680 R14: ffff88801bfd0000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff88802c200000(0063) knlGS:00000000f5f30b40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 0000000000000011 CR3: 00000000632a8000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 49 83 7f 28 00 cmpq $0x0,0x28(%r15) 5: 0f 85 de 07 00 00 jne 0x7e9 b: 4d 89 77 28 mov %r14,0x28(%r15) f: 49 83 7c 24 10 00 cmpq $0x0,0x10(%r12) 15: 0f 85 45 06 00 00 jne 0x660 1b: 4d 8b 7c 24 18 mov 0x18(%r12),%r15 20: 4d 85 ff test %r15,%r15 23: 0f 84 d2 06 00 00 je 0x6fb * 29: 49 8b 47 10 mov 0x10(%r15),%rax <-- trapping instruction 2d: 83 bd 68 ff ff ff ff cmpl $0xffffffff,-0x98(%rbp) 34: 49 89 44 24 18 mov %rax,0x18(%r12) 39: 74 20 je 0x5b 3b: 49 8b 07 mov (%r15),%rax 3e: 48 rex.W