Debian GNU/Linux 7 syzkaller ttyS0 executing program syzkaller login: [ 17.427725] usercopy: kernel memory overwrite attempt detected to ffff88006c851bd4 (kvm_vcpu) (840 bytes) [ 17.428839] ------------[ cut here ]------------ [ 17.429579] kernel BUG at mm/usercopy.c:84! [ 17.429975] invalid opcode: 0000 [#1] SMP KASAN [ 17.430389] Dumping ftrace buffer: [ 17.430722] (ftrace buffer empty) [ 17.431050] Modules linked in: [ 17.431340] CPU: 2 PID: 2988 Comm: syzkaller374041 Not tainted 4.14.0-rc5-next-20171018+ #8 [ 17.432090] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 17.432928] task: ffff88003e280100 task.stack: ffff880039258000 [ 17.433479] RIP: 0010:__check_object_size+0x3a2/0x4f0 [ 17.433952] RSP: 0018:ffff88003925f148 EFLAGS: 00010286 [ 17.434436] RAX: 000000000000005d RBX: ffffffff8511a0e0 RCX: 0000000000000000 [ 17.435076] RDX: 000000000000005d RSI: 1ffff1000724bde9 RDI: ffffed000724be1d [ 17.435715] RBP: ffff88003925f238 R08: 0000000000000001 R09: 0000000000000000 [ 17.436365] R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8511a0a0 [ 17.437092] R13: ffff88006c851bd4 R14: 0000000000000348 R15: ffffea0001b21400 [ 17.437751] FS: 00000000019c1880(0000) GS:ffff88006de00000(0000) knlGS:0000000000000000 [ 17.438496] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 17.439020] CR2: 00007ffdca69ab88 CR3: 000000006bbff000 CR4: 00000000000026e0 [ 17.439687] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 17.440571] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 17.441176] Call Trace: [ 17.441398] ? lock_release+0xa40/0xa40 [ 17.441729] ? check_stack_object+0x140/0x140 [ 17.442085] ? check_noncircular+0x20/0x20 [ 17.442387] ? __might_sleep+0x95/0x190 [ 17.442665] kvm_vcpu_ioctl_set_cpuid2+0x75/0x1a0 [ 17.443000] kvm_arch_vcpu_ioctl+0x1718/0x4710 [ 17.443362] ? find_held_lock+0x35/0x1d0 [ 17.443677] ? kvm_arch_vcpu_put+0x3e0/0x3e0 [ 17.444011] ? depot_save_stack+0x3b5/0x490 [ 17.444342] ? lock_downgrade+0x990/0x990 [ 17.444795] ? do_raw_spin_trylock+0x190/0x190 [ 17.445161] ? is_bpf_text_address+0xa4/0x120 [ 17.445517] ? kernel_text_address+0x102/0x140 [ 17.445872] ? __kernel_text_address+0xd/0x40 [ 17.446255] ? unwind_get_return_address+0x61/0xa0 [ 17.446661] ? trace_hardirqs_off+0xd/0x10 [ 17.447024] ? _raw_spin_unlock_irqrestore+0xa6/0xba [ 17.447450] ? depot_save_stack+0x3b5/0x490 [ 17.447800] ? __vunmap+0x247/0x2e0 [ 17.448102] ? save_stack+0xa3/0xd0 [ 17.448401] ? lock_acquire+0x1d5/0x580 [ 17.448740] ? lock_acquire+0x1d5/0x580 [ 17.449051] ? vcpu_load+0x1c/0x70 [ 17.449331] ? lock_release+0xa40/0xa40 [ 17.449634] ? trace_event_raw_event_sched_switch+0x8a0/0x8a0 [ 17.450080] ? rcu_note_context_switch+0x710/0x710 [ 17.450452] ? __might_sleep+0x95/0x190 [ 17.450719] ? vcpu_load+0x1c/0x70 [ 17.450931] ? __mutex_lock+0x16f/0x19d0 [ 17.451193] ? vcpu_load+0x1c/0x70 [ 17.451407] ? vcpu_load+0x1c/0x70 [ 17.451619] ? trace_hardirqs_off+0xd/0x10 [ 17.451878] ? mutex_lock_io_nested+0x1880/0x1880 [ 17.452224] ? find_held_lock+0x35/0x1d0 [ 17.452468] ? __might_fault+0x110/0x1d0 [ 17.452806] ? lock_downgrade+0x990/0x990 [ 17.453066] ? vmx_vcpu_load+0x9c6/0xdd0 [ 17.453330] ? handle_invept+0x5f0/0x5f0 [ 17.453573] ? __might_sleep+0x95/0x190 [ 17.453813] ? kasan_check_read+0x11/0x20 [ 17.454072] ? _copy_to_user+0xa2/0xc0 [ 17.454316] ? kvm_arch_dev_ioctl+0xc7/0x3b0 [ 17.454577] ? kvm_vm_ioctl_check_extension+0x510/0x510 [ 17.454896] ? kvm_arch_vcpu_load+0x1c1/0x890 [ 17.455176] ? kvm_arch_vcpu_load+0x4b1/0x890 [ 17.455453] ? find_held_lock+0x35/0x1d0 [ 17.455695] ? kvm_arch_dev_ioctl+0x3b0/0x3b0 [ 17.455962] ? __hrtick_start+0x1d0/0x1d0 [ 17.456243] ? avc_has_extended_perms+0x6e5/0x12c0 [ 17.456549] ? vcpu_load+0x4b/0x70 [ 17.456914] kvm_vcpu_ioctl+0x240/0x1010 [ 17.457290] ? __kvm_gfn_to_hva_cache_init+0xbb0/0xbb0 [ 17.457764] ? is_bpf_text_address+0xa4/0x120 [ 17.458173] ? avc_has_extended_perms+0x7fa/0x12c0 [ 17.458615] ? unwind_get_return_address+0x6e/0xa0 [ 17.459060] ? avc_ss_reset+0x110/0x110 [ 17.459418] ? putname+0xee/0x130 [ 17.459729] ? save_stack+0xa3/0xd0 [ 17.460058] ? save_stack+0x43/0xd0 [ 17.460388] ? kasan_slab_free+0x71/0xc0 [ 17.460840] ? kmem_cache_free+0x77/0x280 [ 17.461228] ? putname+0xee/0x130 [ 17.469260] ? do_sys_open+0x31b/0x6d0 [ 17.469571] ? __lock_is_held+0xb6/0x140 [ 17.469853] ? trace_event_raw_event_sched_switch+0x8a0/0x8a0 [ 17.470223] ? rcu_note_context_switch+0x710/0x710 [ 17.470653] ? get_unused_fd_flags+0x190/0x190 [ 17.471042] ? __kvm_gfn_to_hva_cache_init+0xbb0/0xbb0 [ 17.471365] do_vfs_ioctl+0x1b1/0x1520 [ 17.471673] ? _cond_resched+0x14/0x30 [ 17.471981] ? ioctl_preallocate+0x2b0/0x2b0 [ 17.472373] ? selinux_capable+0x40/0x40 [ 17.473017] ? putname+0xf3/0x130 [ 17.473297] ? do_sys_open+0x320/0x6d0 [ 17.473708] ? security_file_ioctl+0x89/0xb0 [ 17.474018] SyS_ioctl+0x8f/0xc0 [ 17.474281] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 17.474715] RIP: 0033:0x437f07 [ 17.474946] RSP: 002b:00007ffdca69ab78 EFLAGS: 00000217 ORIG_RAX: 0000000000000010 [ 17.475497] RAX: ffffffffffffffda RBX: 00007ffdca69b240 RCX: 0000000000437f07 [ 17.476061] RDX: 00007ffdca69b240 RSI: 000000004008ae90 RDI: 0000000000000005 [ 17.476622] RBP: 0000000000000082 R08: 0000000000000001 R09: 0000000000000018 [ 17.477207] R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000000000 [ 17.477768] R13: 0000000000404080 R14: 0000000000000004 R15: 0000000000000000 [ 17.478455] Code: 48 0f 44 da e8 70 f0 c3 ff 48 8b 85 28 ff ff ff 4d 89 f1 4c 89 e9 4c 89 e2 48 89 de 48 c7 c7 a0 a1 11 85 49 89 c0 e8 c3 fb ad ff <0f> 0b 48 c7 c0 60 9f 11 85 eb 96 48 c7 c0 a0 9f 11 85 eb 8d 48 [ 17.480004] RIP: __check_object_size+0x3a2/0x4f0 RSP: ffff88003925f148 [ 17.480563] ---[ end trace 9989db5734986cf2 ]--- [ 17.481112] Kernel panic - not syncing: Fatal exception [ 17.481614] Dumping ftrace buffer: [ 17.481886] (ftrace buffer empty) [ 17.482150] Kernel Offset: disabled [ 17.482414] Rebooting in 86400 seconds..