[ 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 '10.128.0.106' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 116.184155][ T8472] ===================================================== [ 116.191403][ T8472] BUG: KMSAN: uninit-value in fuse_dev_do_write+0xcc8/0xc490 [ 116.198759][ T8472] CPU: 0 PID: 8472 Comm: syz-executor644 Not tainted 5.8.0-rc5-syzkaller #0 [ 116.207663][ T8472] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 116.217785][ T8472] Call Trace: [ 116.221058][ T8472] dump_stack+0x1df/0x240 [ 116.225462][ T8472] kmsan_report+0xf7/0x1e0 [ 116.229856][ T8472] __msan_warning+0x58/0xa0 [ 116.234436][ T8472] fuse_dev_do_write+0xcc8/0xc490 [ 116.239436][ T8472] ? kmsan_get_shadow_origin_ptr+0x81/0xb0 [ 116.245219][ T8472] ? __msan_metadata_ptr_for_load_4+0x10/0x20 [ 116.251280][ T8472] ? __kmalloc_node+0x233/0x11f0 [ 116.256206][ T8472] ? kmsan_get_metadata+0x4f/0x180 [ 116.261385][ T8472] fuse_dev_splice_write+0x1020/0x1230 [ 116.266848][ T8472] ? fuse_dev_fasync+0x170/0x170 [ 116.271851][ T8472] direct_splice_actor+0x1fd/0x580 [ 116.276945][ T8472] ? kmsan_get_metadata+0x4f/0x180 [ 116.282047][ T8472] splice_direct_to_actor+0x6b2/0xf50 [ 116.287400][ T8472] ? do_splice_direct+0x580/0x580 [ 116.292414][ T8472] do_splice_direct+0x342/0x580 [ 116.297247][ T8472] do_sendfile+0x101b/0x1d40 [ 116.301835][ T8472] __se_sys_sendfile64+0x2bb/0x360 [ 116.306924][ T8472] ? kmsan_get_metadata+0x4f/0x180 [ 116.312031][ T8472] __x64_sys_sendfile64+0x56/0x70 [ 116.317049][ T8472] do_syscall_64+0xb0/0x150 [ 116.321528][ T8472] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 116.327396][ T8472] RIP: 0033:0x4402e9 [ 116.331272][ T8472] Code: Bad RIP value. [ 116.335484][ T8472] RSP: 002b:00007ffd9dac5ae8 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 [ 116.344477][ T8472] RAX: ffffffffffffffda RBX: 00007ffd9dac5af0 RCX: 00000000004402e9 [ 116.352607][ T8472] RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000004 [ 116.360564][ T8472] RBP: 00000000006ca018 R08: 65732f636f72702f R09: 65732f636f72702f [ 116.368859][ T8472] R10: 000000000000edc0 R11: 0000000000000246 R12: 0000000000401b50 [ 116.376813][ T8472] R13: 0000000000401be0 R14: 0000000000000000 R15: 0000000000000000 [ 116.384877][ T8472] [ 116.387192][ T8472] Uninit was stored to memory at: [ 116.392211][ T8472] kmsan_internal_chain_origin+0xad/0x130 [ 116.397923][ T8472] kmsan_memcpy_memmove_metadata+0x272/0x2e0 [ 116.403883][ T8472] kmsan_memcpy_metadata+0xb/0x10 [ 116.408886][ T8472] __msan_memcpy+0x43/0x50 [ 116.413280][ T8472] fuse_dev_do_write+0x4e6/0xc490 [ 116.418282][ T8472] fuse_dev_splice_write+0x1020/0x1230 [ 116.423716][ T8472] direct_splice_actor+0x1fd/0x580 [ 116.428803][ T8472] splice_direct_to_actor+0x6b2/0xf50 [ 116.434168][ T8472] do_splice_direct+0x342/0x580 [ 116.439030][ T8472] do_sendfile+0x101b/0x1d40 [ 116.443596][ T8472] __se_sys_sendfile64+0x2bb/0x360 [ 116.448888][ T8472] __x64_sys_sendfile64+0x56/0x70 [ 116.453888][ T8472] do_syscall_64+0xb0/0x150 [ 116.459321][ T8472] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 116.465182][ T8472] [ 116.467489][ T8472] Uninit was created at: [ 116.471884][ T8472] kmsan_save_stack_with_flags+0x3c/0x90 [ 116.477498][ T8472] kmsan_alloc_page+0xb9/0x180 [ 116.482237][ T8472] __alloc_pages_nodemask+0x56a2/0x5dc0 [ 116.487756][ T8472] alloc_pages_current+0x672/0x990 [ 116.492846][ T8472] push_pipe+0x605/0xb70 [ 116.497061][ T8472] iov_iter_get_pages_alloc+0x18a9/0x21c0 [ 116.502755][ T8472] do_splice_to+0x4fc/0x14f0 [ 116.507321][ T8472] splice_direct_to_actor+0x45c/0xf50 [ 116.512667][ T8472] do_splice_direct+0x342/0x580 [ 116.517496][ T8472] do_sendfile+0x101b/0x1d40 [ 116.522066][ T8472] __se_sys_sendfile64+0x2bb/0x360 [ 116.527150][ T8472] __x64_sys_sendfile64+0x56/0x70 [ 116.532158][ T8472] do_syscall_64+0xb0/0x150 [ 116.536639][ T8472] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 116.542500][ T8472] ===================================================== [ 116.549401][ T8472] Disabling lock debugging due to kernel taint [ 116.555525][ T8472] Kernel panic - not syncing: panic_on_warn set ... [ 116.562090][ T8472] CPU: 0 PID: 8472 Comm: syz-executor644 Tainted: G B 5.8.0-rc5-syzkaller #0 [ 116.572129][ T8472] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 116.582187][ T8472] Call Trace: [ 116.585458][ T8472] dump_stack+0x1df/0x240 [ 116.589767][ T8472] panic+0x3d5/0xc3e [ 116.593656][ T8472] kmsan_report+0x1df/0x1e0 [ 116.598235][ T8472] __msan_warning+0x58/0xa0 [ 116.603325][ T8472] fuse_dev_do_write+0xcc8/0xc490 [ 116.608327][ T8472] ? kmsan_get_shadow_origin_ptr+0x81/0xb0 [ 116.614203][ T8472] ? __msan_metadata_ptr_for_load_4+0x10/0x20 [ 116.620247][ T8472] ? __kmalloc_node+0x233/0x11f0 [ 116.625175][ T8472] ? kmsan_get_metadata+0x4f/0x180 [ 116.630279][ T8472] fuse_dev_splice_write+0x1020/0x1230 [ 116.635740][ T8472] ? fuse_dev_fasync+0x170/0x170 [ 116.640656][ T8472] direct_splice_actor+0x1fd/0x580 [ 116.645749][ T8472] ? kmsan_get_metadata+0x4f/0x180 [ 116.650924][ T8472] splice_direct_to_actor+0x6b2/0xf50 [ 116.656295][ T8472] ? do_splice_direct+0x580/0x580 [ 116.661330][ T8472] do_splice_direct+0x342/0x580 [ 116.666173][ T8472] do_sendfile+0x101b/0x1d40 [ 116.670760][ T8472] __se_sys_sendfile64+0x2bb/0x360 [ 116.675854][ T8472] ? kmsan_get_metadata+0x4f/0x180 [ 116.680964][ T8472] __x64_sys_sendfile64+0x56/0x70 [ 116.685971][ T8472] do_syscall_64+0xb0/0x150 [ 116.690455][ T8472] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 116.696329][ T8472] RIP: 0033:0x4402e9 [ 116.700195][ T8472] Code: Bad RIP value. [ 116.704237][ T8472] RSP: 002b:00007ffd9dac5ae8 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 [ 116.712626][ T8472] RAX: ffffffffffffffda RBX: 00007ffd9dac5af0 RCX: 00000000004402e9 [ 116.720573][ T8472] RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000004 [ 116.728524][ T8472] RBP: 00000000006ca018 R08: 65732f636f72702f R09: 65732f636f72702f [ 116.736564][ T8472] R10: 000000000000edc0 R11: 0000000000000246 R12: 0000000000401b50 [ 116.744624][ T8472] R13: 0000000000401be0 R14: 0000000000000000 R15: 0000000000000000 [ 116.754469][ T8472] Kernel Offset: 0xf600000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 116.766031][ T8472] Rebooting in 86400 seconds..