Hello, syzbot found the following crash on: HEAD commit: 4f8a3cc1 Merge tag 'x86-urgent-2020-04-12' of git://git.ke.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=104b9407e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=3bfbde87e8e65624 dashboard link: https://syzkaller.appspot.com/bug?extid=2e0179e5185bcd5b9440 compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13e78c7de00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14cf613fe00000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+2e0179e5185bcd5b9440@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-out-of-bounds in search_memslots include/linux/kvm_host.h:1051 [inline] BUG: KASAN: slab-out-of-bounds in __gfn_to_memslot include/linux/kvm_host.h:1063 [inline] BUG: KASAN: slab-out-of-bounds in gfn_to_memslot+0x275/0x470 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1597 Read of size 8 at addr ffff888097b31468 by task syz-executor165/9960 CPU: 0 PID: 9960 Comm: syz-executor165 Not tainted 5.6.0-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+0x1e9/0x30e lib/dump_stack.c:118 print_address_description+0x74/0x5c0 mm/kasan/report.c:382 __kasan_report+0x103/0x1a0 mm/kasan/report.c:511 kasan_report+0x4d/0x80 mm/kasan/common.c:625 Allocated by task 9966: save_stack mm/kasan/common.c:49 [inline] set_track mm/kasan/common.c:57 [inline] __kasan_kmalloc+0x114/0x160 mm/kasan/common.c:495 kmalloc_node include/linux/slab.h:578 [inline] kvmalloc_node+0x81/0x100 mm/util.c:574 kvmalloc include/linux/mm.h:757 [inline] kvzalloc include/linux/mm.h:765 [inline] kvm_dup_memslots arch/x86/kvm/../../../virt/kvm/kvm_main.c:1101 [inline] kvm_set_memslot+0x124/0x15b0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1118 __kvm_set_memory_region+0x1388/0x16c0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1300 kvm_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1321 [inline] kvm_vm_ioctl_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1333 [inline] kvm_vm_ioctl+0x930/0x2530 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3604 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl fs/ioctl.c:763 [inline] __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl+0xf9/0x160 fs/ioctl.c:770 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Freed by task 8700: save_stack mm/kasan/common.c:49 [inline] set_track mm/kasan/common.c:57 [inline] kasan_set_free_info mm/kasan/common.c:317 [inline] __kasan_slab_free+0x125/0x190 mm/kasan/common.c:456 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x220 mm/slab.c:3757 kvm_free_memslots arch/x86/kvm/../../../virt/kvm/kvm_main.c:601 [inline] kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:810 [inline] kvm_put_kvm+0xa8d/0xcb0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:828 kvm_vm_release+0x42/0x50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:851 __fput+0x2ed/0x750 fs/file_table.c:280 task_work_run+0x147/0x1d0 kernel/task_work.c:123 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop arch/x86/entry/common.c:165 [inline] prepare_exit_to_usermode+0x48e/0x600 arch/x86/entry/common.c:196 entry_SYSCALL_64_after_hwframe+0x49/0xb3 The buggy address belongs to the object at ffff888097b31000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1128 bytes inside of 2048-byte region [ffff888097b31000, ffff888097b31800) The buggy address belongs to the page: page:ffffea00025ecc40 refcount:1 mapcount:0 mapping:00000000499db978 index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00029ef288 ffffea0002a34408 ffff8880aa400e00 raw: 0000000000000000 ffff888097b31000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888097b31300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888097b31380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888097b31400: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc ^ ffff888097b31480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888097b31500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this bug, for details see: https://goo.gl/tpsmEJ#testing-patches
