[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 61.414724][ T26] audit: type=1800 audit(1575358560.256:25): pid=9064 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 61.438744][ T26] audit: type=1800 audit(1575358560.256:26): pid=9064 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 61.490062][ T26] audit: type=1800 audit(1575358560.256:27): pid=9064 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.115' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 73.323467][ T9216] ================================================================== [ 73.323513][ T9216] BUG: KASAN: global-out-of-bounds in vga16fb_imageblit+0x1c8b/0x2200 [ 73.323521][ T9216] Read of size 2 at addr ffffffff8874be58 by task syz-executor641/9216 [ 73.323523][ T9216] [ 73.323533][ T9216] CPU: 0 PID: 9216 Comm: syz-executor641 Not tainted 5.4.0-syzkaller #0 [ 73.323539][ T9216] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.323542][ T9216] Call Trace: [ 73.323555][ T9216] dump_stack+0x197/0x210 [ 73.323564][ T9216] ? vga16fb_imageblit+0x1c8b/0x2200 [ 73.323575][ T9216] print_address_description.constprop.0.cold+0x5/0x30b [ 73.323584][ T9216] ? vga16fb_imageblit+0x1c8b/0x2200 [ 73.323592][ T9216] ? vga16fb_imageblit+0x1c8b/0x2200 [ 73.323600][ T9216] __kasan_report.cold+0x1b/0x41 [ 73.323610][ T9216] ? vga16fb_imageblit+0x1c8b/0x2200 [ 73.323619][ T9216] kasan_report+0x12/0x20 [ 73.323628][ T9216] __asan_report_load2_noabort+0x14/0x20 [ 73.323636][ T9216] vga16fb_imageblit+0x1c8b/0x2200 [ 73.323653][ T9216] soft_cursor+0x4fb/0xa30 [ 73.323664][ T9216] ? __lock_task_sighand+0x125/0x2f0 [ 73.323678][ T9216] bit_cursor+0x12fc/0x1a60 [ 73.323691][ T9216] ? bit_clear+0x530/0x530 [ 73.323701][ T9216] ? find_held_lock+0x35/0x130 [ 73.323716][ T9216] ? __sanitizer_cov_trace_switch+0x49/0x80 [ 73.323726][ T9216] ? get_color+0x225/0x430 [ 73.323736][ T9216] fbcon_cursor+0x487/0x660 [ 73.323743][ T9216] ? bit_clear+0x530/0x530 [ 73.323753][ T9216] hide_cursor+0x9d/0x2b0 [ 73.323762][ T9216] redraw_screen+0x60b/0x7d0 [ 73.323771][ T9216] ? respond_string+0x2c0/0x2c0 [ 73.323783][ T9216] vc_do_resize+0x10c9/0x1460 [ 73.323791][ T9216] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 73.323807][ T9216] ? vc_uniscr_alloc+0xd0/0xd0 [ 73.323821][ T9216] vc_resize+0x4d/0x60 [ 73.323830][ T9216] fbcon_modechanged+0x367/0x790 [ 73.323841][ T9216] fbcon_update_vcs+0x42/0x50 [ 73.323849][ T9216] fb_set_var+0xb32/0xdd0 [ 73.323857][ T9216] ? fb_blank+0x1a0/0x1a0 [ 73.323865][ T9216] ? lock_acquire+0x190/0x410 [ 73.323878][ T9216] ? __mutex_lock+0x458/0x13c0 [ 73.323885][ T9216] ? down+0x50/0x90 [ 73.323904][ T9216] ? do_fb_ioctl+0x335/0x7d0 [ 73.323916][ T9216] do_fb_ioctl+0x390/0x7d0 [ 73.323924][ T9216] ? fb_mmap+0x520/0x520 [ 73.323931][ T9216] ? tomoyo_path_number_perm+0x214/0x520 [ 73.323940][ T9216] ? find_held_lock+0x35/0x130 [ 73.323948][ T9216] ? tomoyo_path_number_perm+0x214/0x520 [ 73.323959][ T9216] ? lock_downgrade+0x920/0x920 [ 73.323966][ T9216] ? lockdep_hardirqs_on+0x421/0x5e0 [ 73.323976][ T9216] ? tomoyo_path_number_perm+0x454/0x520 [ 73.323999][ T9216] fb_ioctl+0xe6/0x130 [ 73.324005][ T9216] ? do_fb_ioctl+0x7d0/0x7d0 [ 73.324013][ T9216] do_vfs_ioctl+0xdb6/0x13e0 [ 73.324023][ T9216] ? compat_ioctl_preallocate+0x210/0x210 [ 73.324032][ T9216] ? kmem_cache_free+0x26b/0x320 [ 73.324042][ T9216] ? putname+0xf4/0x130 [ 73.324050][ T9216] ? do_sys_open+0x31d/0x5d0 [ 73.324061][ T9216] ? tomoyo_file_ioctl+0x23/0x30 [ 73.324069][ T9216] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 73.324076][ T9216] ? security_file_ioctl+0x8d/0xc0 [ 73.324085][ T9216] ksys_ioctl+0xab/0xd0 [ 73.324094][ T9216] __x64_sys_ioctl+0x73/0xb0 [ 73.324106][ T9216] do_syscall_64+0xfa/0x790 [ 73.324117][ T9216] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 73.324124][ T9216] RIP: 0033:0x440309 [ 73.324134][ T9216] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 73.324138][ T9216] RSP: 002b:00007fffb34a8d88 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 73.324151][ T9216] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440309 [ 73.324156][ T9216] RDX: 0000000020000340 RSI: 0000000000004601 RDI: 0000000000000003 [ 73.324161][ T9216] RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 [ 73.324166][ T9216] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401b90 [ 73.324170][ T9216] R13: 0000000000401c20 R14: 0000000000000000 R15: 0000000000000000 [ 73.324180][ T9216] [ 73.324183][ T9216] The buggy address belongs to the variable: [ 73.324191][ T9216] transl_h+0x38/0x40 [ 73.324193][ T9216] [ 73.324196][ T9216] Memory state around the buggy address: [ 73.324203][ T9216] ffffffff8874bd00: 00 00 00 00 fa fa fa fa 00 00 00 00 fa fa fa fa [ 73.324209][ T9216] ffffffff8874bd80: 00 00 00 00 00 fa fa fa fa fa fa fa 04 fa fa fa [ 73.324215][ T9216] >ffffffff8874be00: fa fa fa fa 00 00 00 00 fa fa fa fa 00 00 00 00 [ 73.324219][ T9216] ^ [ 73.324224][ T9216] ffffffff8874be80: fa fa fa fa 00 01 fa fa fa fa fa fa 00 00 00 04 [ 73.324230][ T9216] ffffffff8874bf00: fa fa fa fa 00 00 04 fa fa fa fa fa 00 00 00 00 [ 73.324233][ T9216] ================================================================== [ 73.324236][ T9216] Disabling lock debugging due to kernel taint [ 73.324241][ T9216] Kernel panic - not syncing: panic_on_warn set ... [ 73.324249][ T9216] CPU: 0 PID: 9216 Comm: syz-executor641 Tainted: G B 5.4.0-syzkaller #0 [ 73.324252][ T9216] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.324254][ T9216] Call Trace: [ 73.324262][ T9216] dump_stack+0x197/0x210 [ 73.324271][ T9216] panic+0x2e3/0x75c [ 73.324278][ T9216] ? add_taint.cold+0x16/0x16 [ 73.324290][ T9216] ? trace_hardirqs_on+0x67/0x240 [ 73.324297][ T9216] ? trace_hardirqs_on+0x5e/0x240 [ 73.324305][ T9216] ? vga16fb_imageblit+0x1c8b/0x2200 [ 73.324311][ T9216] end_report+0x47/0x4f [ 73.324319][ T9216] ? vga16fb_imageblit+0x1c8b/0x2200 [ 73.324325][ T9216] __kasan_report.cold+0xe/0x41 [ 73.324333][ T9216] ? vga16fb_imageblit+0x1c8b/0x2200 [ 73.324340][ T9216] kasan_report+0x12/0x20 [ 73.324348][ T9216] __asan_report_load2_noabort+0x14/0x20 [ 73.324355][ T9216] vga16fb_imageblit+0x1c8b/0x2200 [ 73.324366][ T9216] soft_cursor+0x4fb/0xa30 [ 73.324374][ T9216] ? __lock_task_sighand+0x125/0x2f0 [ 73.324384][ T9216] bit_cursor+0x12fc/0x1a60 [ 73.324394][ T9216] ? bit_clear+0x530/0x530 [ 73.324401][ T9216] ? find_held_lock+0x35/0x130 [ 73.324411][ T9216] ? __sanitizer_cov_trace_switch+0x49/0x80 [ 73.324418][ T9216] ? get_color+0x225/0x430 [ 73.324426][ T9216] fbcon_cursor+0x487/0x660 [ 73.324433][ T9216] ? bit_clear+0x530/0x530 [ 73.324440][ T9216] hide_cursor+0x9d/0x2b0 [ 73.324447][ T9216] redraw_screen+0x60b/0x7d0 [ 73.324454][ T9216] ? respond_string+0x2c0/0x2c0 [ 73.324463][ T9216] vc_do_resize+0x10c9/0x1460 [ 73.324470][ T9216] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 73.324481][ T9216] ? vc_uniscr_alloc+0xd0/0xd0 [ 73.324490][ T9216] vc_resize+0x4d/0x60 [ 73.324498][ T9216] fbcon_modechanged+0x367/0x790 [ 73.324507][ T9216] fbcon_update_vcs+0x42/0x50 [ 73.324513][ T9216] fb_set_var+0xb32/0xdd0 [ 73.324520][ T9216] ? fb_blank+0x1a0/0x1a0 [ 73.324526][ T9216] ? lock_acquire+0x190/0x410 [ 73.324535][ T9216] ? __mutex_lock+0x458/0x13c0 [ 73.324542][ T9216] ? down+0x50/0x90 [ 73.324553][ T9216] ? do_fb_ioctl+0x335/0x7d0 [ 73.324562][ T9216] do_fb_ioctl+0x390/0x7d0 [ 73.324568][ T9216] ? fb_mmap+0x520/0x520 [ 73.324575][ T9216] ? tomoyo_path_number_perm+0x214/0x520 [ 73.324583][ T9216] ? find_held_lock+0x35/0x130 [ 73.324590][ T9216] ? tomoyo_path_number_perm+0x214/0x520 [ 73.324598][ T9216] ? lock_downgrade+0x920/0x920 [ 73.324604][ T9216] ? lockdep_hardirqs_on+0x421/0x5e0 [ 73.324612][ T9216] ? tomoyo_path_number_perm+0x454/0x520 [ 73.324626][ T9216] fb_ioctl+0xe6/0x130 [ 73.324632][ T9216] ? do_fb_ioctl+0x7d0/0x7d0 [ 73.324638][ T9216] do_vfs_ioctl+0xdb6/0x13e0 [ 73.324646][ T9216] ? compat_ioctl_preallocate+0x210/0x210 [ 73.324653][ T9216] ? kmem_cache_free+0x26b/0x320 [ 73.324661][ T9216] ? putname+0xf4/0x130 [ 73.324667][ T9216] ? do_sys_open+0x31d/0x5d0 [ 73.324675][ T9216] ? tomoyo_file_ioctl+0x23/0x30 [ 73.324683][ T9216] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 73.324689][ T9216] ? security_file_ioctl+0x8d/0xc0 [ 73.324696][ T9216] ksys_ioctl+0xab/0xd0 [ 73.324703][ T9216] __x64_sys_ioctl+0x73/0xb0 [ 73.324711][ T9216] do_syscall_64+0xfa/0x790 [ 73.324719][ T9216] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 73.324724][ T9216] RIP: 0033:0x440309 [ 73.324730][ T9216] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 73.324734][ T9216] RSP: 002b:00007fffb34a8d88 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 73.324741][ T9216] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440309 [ 73.324745][ T9216] RDX: 0000000020000340 RSI: 0000000000004601 RDI: 0000000000000003 [ 73.324749][ T9216] RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 [ 73.324753][ T9216] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401b90 [ 73.324757][ T9216] R13: 0000000000401c20 R14: 0000000000000000 R15: 0000000000000000 [ 73.326479][ T9216] Kernel Offset: disabled [ 74.192731][ T9216] Rebooting in 86400 seconds..