[ OK ] Started OpenBSD Secure Shell server. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.16' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 143.498443][ T8454] ===================================================== [ 143.505452][ T8454] BUG: KMSAN: uninit-value in vhost_chr_write_iter+0x256/0x14f0 [ 143.513077][ T8454] CPU: 0 PID: 8454 Comm: syz-executor540 Not tainted 5.8.0-rc5-syzkaller #0 [ 143.521732][ T8454] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 143.531832][ T8454] Call Trace: [ 143.535167][ T8454] dump_stack+0x1df/0x240 [ 143.539518][ T8454] kmsan_report+0xf7/0x1e0 [ 143.543926][ T8454] __msan_warning+0x58/0xa0 [ 143.548421][ T8454] vhost_chr_write_iter+0x256/0x14f0 [ 143.553700][ T8454] ? __msan_metadata_ptr_for_store_1+0x13/0x20 [ 143.559857][ T8454] ? kmsan_get_metadata+0x4f/0x180 [ 143.564977][ T8454] ? kmsan_get_shadow_origin_ptr+0x81/0xb0 [ 143.570782][ T8454] vhost_net_chr_write_iter+0x96/0xc0 [ 143.576149][ T8454] ? vhost_net_chr_read_iter+0x130/0x130 [ 143.581794][ T8454] __kernel_write+0xba1/0x1220 [ 143.586597][ T8454] write_pipe_buf+0x1f9/0x2a0 [ 143.591278][ T8454] __splice_from_pipe+0x565/0xf00 [ 143.596299][ T8454] ? __ia32_sys_tee+0x70/0x70 [ 143.601002][ T8454] direct_splice_actor+0x3af/0x580 [ 143.606139][ T8454] splice_direct_to_actor+0x6b2/0xf50 [ 143.611510][ T8454] ? do_splice_direct+0x580/0x580 [ 143.616552][ T8454] do_splice_direct+0x342/0x580 [ 143.621423][ T8454] do_sendfile+0x101b/0x1d40 [ 143.626045][ T8454] __se_sys_sendfile64+0x2bb/0x360 [ 143.631154][ T8454] ? kmsan_get_metadata+0x4f/0x180 [ 143.636268][ T8454] __x64_sys_sendfile64+0x56/0x70 [ 143.641306][ T8454] do_syscall_64+0xb0/0x150 [ 143.645810][ T8454] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 143.651689][ T8454] RIP: 0033:0x440299 [ 143.655583][ T8454] Code: Bad RIP value. [ 143.659635][ T8454] RSP: 002b:00007fffaacb3de8 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 [ 143.668904][ T8454] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440299 [ 143.676870][ T8454] RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000004 [ 143.684854][ T8454] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 [ 143.692818][ T8454] R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000401aa0 [ 143.700782][ T8454] R13: 0000000000401b30 R14: 0000000000000000 R15: 0000000000000000 [ 143.708768][ T8454] [ 143.711092][ T8454] Uninit was stored to memory at: [ 143.716112][ T8454] kmsan_internal_chain_origin+0xad/0x130 [ 143.721833][ T8454] kmsan_memcpy_memmove_metadata+0x272/0x2e0 [ 143.727825][ T8454] kmsan_memcpy_metadata+0xb/0x10 [ 143.732835][ T8454] __msan_memcpy+0x43/0x50 [ 143.737258][ T8454] _copy_from_iter+0x1518/0x1c30 [ 143.742197][ T8454] vhost_chr_write_iter+0xb6/0x14f0 [ 143.747390][ T8454] vhost_net_chr_write_iter+0x96/0xc0 [ 143.752777][ T8454] __kernel_write+0xba1/0x1220 [ 143.757531][ T8454] write_pipe_buf+0x1f9/0x2a0 [ 143.762200][ T8454] __splice_from_pipe+0x565/0xf00 [ 143.767209][ T8454] direct_splice_actor+0x3af/0x580 [ 143.772329][ T8454] splice_direct_to_actor+0x6b2/0xf50 [ 143.777686][ T8454] do_splice_direct+0x342/0x580 [ 143.782526][ T8454] do_sendfile+0x101b/0x1d40 [ 143.787113][ T8454] __se_sys_sendfile64+0x2bb/0x360 [ 143.792209][ T8454] __x64_sys_sendfile64+0x56/0x70 [ 143.797224][ T8454] do_syscall_64+0xb0/0x150 [ 143.801721][ T8454] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 143.807591][ T8454] [ 143.809902][ T8454] Uninit was created at: [ 143.814136][ T8454] kmsan_save_stack_with_flags+0x3c/0x90 [ 143.819759][ T8454] kmsan_alloc_page+0xb9/0x180 [ 143.824535][ T8454] __alloc_pages_nodemask+0x56a2/0x5dc0 [ 143.830076][ T8454] alloc_pages_current+0x672/0x990 [ 143.835180][ T8454] push_pipe+0x605/0xb70 [ 143.839429][ T8454] iov_iter_get_pages_alloc+0x18a9/0x21c0 [ 143.845142][ T8454] do_splice_to+0x4fc/0x14f0 [ 143.849745][ T8454] splice_direct_to_actor+0x45c/0xf50 [ 143.855123][ T8454] do_splice_direct+0x342/0x580 [ 143.859976][ T8454] do_sendfile+0x101b/0x1d40 [ 143.864576][ T8454] __se_sys_sendfile64+0x2bb/0x360 [ 143.869689][ T8454] __x64_sys_sendfile64+0x56/0x70 [ 143.874701][ T8454] do_syscall_64+0xb0/0x150 [ 143.879198][ T8454] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 143.885063][ T8454] ===================================================== [ 143.891972][ T8454] Disabling lock debugging due to kernel taint [ 143.898120][ T8454] Kernel panic - not syncing: panic_on_warn set ... [ 143.904692][ T8454] CPU: 0 PID: 8454 Comm: syz-executor540 Tainted: G B 5.8.0-rc5-syzkaller #0 [ 143.914731][ T8454] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 143.924774][ T8454] Call Trace: [ 143.928068][ T8454] dump_stack+0x1df/0x240 [ 143.932406][ T8454] panic+0x3d5/0xc3e [ 143.936338][ T8454] kmsan_report+0x1df/0x1e0 [ 143.940845][ T8454] __msan_warning+0x58/0xa0 [ 143.945370][ T8454] vhost_chr_write_iter+0x256/0x14f0 [ 143.950656][ T8454] ? __msan_metadata_ptr_for_store_1+0x13/0x20 [ 143.956826][ T8454] ? kmsan_get_metadata+0x4f/0x180 [ 143.961944][ T8454] ? kmsan_get_shadow_origin_ptr+0x81/0xb0 [ 143.967769][ T8454] vhost_net_chr_write_iter+0x96/0xc0 [ 143.973140][ T8454] ? vhost_net_chr_read_iter+0x130/0x130 [ 143.978778][ T8454] __kernel_write+0xba1/0x1220 [ 143.983578][ T8454] write_pipe_buf+0x1f9/0x2a0 [ 143.988255][ T8454] __splice_from_pipe+0x565/0xf00 [ 143.993280][ T8454] ? __ia32_sys_tee+0x70/0x70 [ 143.997970][ T8454] direct_splice_actor+0x3af/0x580 [ 144.003089][ T8454] splice_direct_to_actor+0x6b2/0xf50 [ 144.008465][ T8454] ? do_splice_direct+0x580/0x580 [ 144.013523][ T8454] do_splice_direct+0x342/0x580 [ 144.018410][ T8454] do_sendfile+0x101b/0x1d40 [ 144.023045][ T8454] __se_sys_sendfile64+0x2bb/0x360 [ 144.028150][ T8454] ? kmsan_get_metadata+0x4f/0x180 [ 144.033260][ T8454] __x64_sys_sendfile64+0x56/0x70 [ 144.038304][ T8454] do_syscall_64+0xb0/0x150 [ 144.042817][ T8454] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 144.048690][ T8454] RIP: 0033:0x440299 [ 144.052563][ T8454] Code: Bad RIP value. [ 144.056608][ T8454] RSP: 002b:00007fffaacb3de8 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 [ 144.065015][ T8454] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440299 [ 144.072984][ T8454] RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000004 [ 144.080953][ T8454] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 [ 144.088910][ T8454] R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000401aa0 [ 144.096866][ T8454] R13: 0000000000401b30 R14: 0000000000000000 R15: 0000000000000000 [ 144.105897][ T8454] Kernel Offset: 0xe600000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 144.117433][ T8454] Rebooting in 86400 seconds..