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BUG: KASAN: slab-out-of-bounds in squashfs_get_id+0x1ae/0x1d0 fs/squashfs/id.c:51
Read of size 8 at addr ffff888093f598a0 by task syz-executor.4/27824

CPU: 1 PID: 27824 Comm: syz-executor.4 Not tainted 4.19.155-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2fe lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1c7 mm/kasan/report.c:354
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433
 squashfs_get_id+0x1ae/0x1d0 fs/squashfs/id.c:51
 squashfs_new_inode fs/squashfs/inode.c:64 [inline]
 squashfs_read_inode+0x1b4/0x1b40 fs/squashfs/inode.c:133
 squashfs_fill_super+0x1655/0x1c00 fs/squashfs/super.c:318
 mount_bdev+0x2fc/0x3b0 fs/super.c:1158
 mount_fs+0xa3/0x30c fs/super.c:1261
 vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961
 vfs_kern_mount fs/namespace.c:951 [inline]
 do_new_mount fs/namespace.c:2469 [inline]
 do_mount+0x113c/0x2f10 fs/namespace.c:2799
 ksys_mount+0xcf/0x130 fs/namespace.c:3015
 __do_sys_mount fs/namespace.c:3029 [inline]
 __se_sys_mount fs/namespace.c:3026 [inline]
 __x64_sys_mount+0xba/0x150 fs/namespace.c:3026
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x46090a
Code: b8 a6 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 ad 89 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 8a 89 fb ff c3 66 0f 1f 84 00 00 00 00 00
RSP: 002b:00007f0352f90a88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f0352f90b20 RCX: 000000000046090a
RDX: 0000000020000000 RSI: 0000000020000080 RDI: 00007f0352f90ae0
RBP: 00007f0352f90ae0 R08: 00007f0352f90b20 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000
R13: 0000000020000080 R14: 0000000020000200 R15: 0000000020000040

Allocated by task 27785:
 kmem_cache_alloc_trace+0x12f/0x380 mm/slab.c:3625
 kmalloc include/linux/slab.h:515 [inline]
 kzalloc include/linux/slab.h:709 [inline]
 kvm_create_vm_debugfs arch/x86/kvm/../../../virt/kvm/kvm_main.c:643 [inline]
 kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:3451 [inline]
 kvm_dev_ioctl+0x88a/0x16e0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3478
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688
 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 27783:
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcc/0x210 mm/slab.c:3822
 kvm_destroy_vm_debugfs arch/x86/kvm/../../../virt/kvm/kvm_main.c:619 [inline]
 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:790 [inline]
 kvm_put_kvm+0x19a/0xc70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:832
 kvm_vcpu_release+0x77/0xa0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2640
 __fput+0x2ce/0x890 fs/file_table.c:278
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff888093f59880
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes to the right of
 32-byte region [ffff888093f59880, ffff888093f598a0)
The buggy address belongs to the page:
page:ffffea00024fd640 count:1 mapcount:0 mapping:ffff88813bff01c0 index:0xffff888093f59fc1
flags: 0xfff00000000100(slab)
raw: 00fff00000000100 ffffea0002ca3008 ffffea000297fe08 ffff88813bff01c0
raw: ffff888093f59fc1 ffff888093f59000 000000010000003f 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888093f59780: 05 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc
 ffff888093f59800: fb fb fb fb fc fc fc fc 00 fc fc fc fc fc fc fc
>ffff888093f59880: fb fb fb fb fc fc fc fc 05 fc fc fc fc fc fc fc
                               ^
 ffff888093f59900: fb fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc
 ffff888093f59980: 00 00 00 02 fc fc fc fc 00 00 00 fc fc fc fc fc
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