================================================================== BUG: KASAN: slab-out-of-bounds in kvm_clear_dirty_log_protect+0x8cf/0x970 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1261 Read of size 8 at addr ffff8880a78e8190 by task syz-executor2/1026 CPU: 1 PID: 1026 Comm: syz-executor2 Not tainted 4.20.0+ #9 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+0x1db/0x2d0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135 kvm_clear_dirty_log_protect+0x8cf/0x970 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1261 kvm_vm_ioctl_clear_dirty_log+0xff/0x260 arch/x86/kvm/x86.c:4468 kvm_vm_ioctl+0xc19/0x1fe0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3126 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x107b/0x17d0 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457ec9 Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ff6751c9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 0000000020000080 RSI: 00000000c018aec0 RDI: 0000000000000004 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff6751ca6d4 R13: 00000000004c9ef0 R14: 00000000004d2a10 R15: 00000000ffffffff Allocated by task 1026: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] kasan_kmalloc mm/kasan/common.c:482 [inline] kasan_kmalloc+0xcf/0xe0 mm/kasan/common.c:455 __do_kmalloc_node mm/slab.c:3671 [inline] __kmalloc_node+0x4e/0x70 mm/slab.c:3678 kmalloc_node include/linux/slab.h:588 [inline] kvmalloc_node+0x68/0x100 mm/util.c:416 kvmalloc include/linux/mm.h:602 [inline] kvzalloc include/linux/mm.h:610 [inline] kvm_create_dirty_bitmap arch/x86/kvm/../../../virt/kvm/kvm_main.c:792 [inline] __kvm_set_memory_region+0x1da1/0x2c40 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1017 kvm_set_memory_region+0x2f/0x60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1083 kvm_vm_ioctl_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1095 [inline] kvm_vm_ioctl+0xafa/0x1fe0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3107 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x107b/0x17d0 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 32297: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:444 kasan_slab_free+0xe/0x10 mm/kasan/common.c:452 __cache_free mm/slab.c:3485 [inline] kfree+0xcf/0x230 mm/slab.c:3804 kvm_destroy_vm_debugfs arch/x86/kvm/../../../virt/kvm/kvm_main.c:585 [inline] kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:729 [inline] kvm_put_kvm+0x25f/0xff0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:769 kvm_vm_release+0x44/0x60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:780 __fput+0x3c5/0xb10 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x1f4/0x2b0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x32a/0x3b0 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x696/0x800 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880a78e8180 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 16 bytes inside of 32-byte region [ffff8880a78e8180, ffff8880a78e81a0) The buggy address belongs to the page: page:ffffea00029e3a00 count:1 mapcount:0 mapping:ffff88812c3f01c0 index:0xffff8880a78e8fc1 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00021e3988 ffffea00026cfd08 ffff88812c3f01c0 raw: ffff8880a78e8fc1 ffff8880a78e8000 0000000100000025 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a78e8080: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8880a78e8100: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc >ffff8880a78e8180: 00 00 fc fc fc fc fc fc fb fb fb fb fc fc fc fc ^ ffff8880a78e8200: fb fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ffff8880a78e8280: fb fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ==================================================================