[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.191' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 43.025944] ================================================================== [ 43.033555] BUG: KASAN: use-after-free in vgem_gem_dumb_create+0x22c/0x240 [ 43.041046] Read of size 8 at addr ffff888092fb1440 by task syz-executor256/10161 [ 43.048973] [ 43.050726] CPU: 1 PID: 10161 Comm: syz-executor256 Not tainted 4.19.193-syzkaller #0 [ 43.058786] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.068193] Call Trace: [ 43.070809] dump_stack+0x1fc/0x2ef [ 43.074446] print_address_description.cold+0x54/0x219 [ 43.079756] kasan_report_error.cold+0x8a/0x1b9 [ 43.084435] ? vgem_gem_dumb_create+0x22c/0x240 [ 43.089132] __asan_report_load8_noabort+0x88/0x90 [ 43.094107] ? drm_gem_object_put_unlocked+0xd0/0x180 [ 43.099308] ? vgem_gem_dumb_create+0x22c/0x240 [ 43.104015] vgem_gem_dumb_create+0x22c/0x240 [ 43.108625] drm_mode_create_dumb+0x27c/0x300 [ 43.113189] drm_ioctl_kernel+0x208/0x2a0 [ 43.117343] ? drm_mode_create_dumb+0x300/0x300 [ 43.122011] ? drm_ioctl_permit+0x210/0x210 [ 43.126333] ? __might_fault+0x192/0x1d0 [ 43.130399] drm_ioctl+0x507/0x9c0 [ 43.133953] ? drm_mode_create_dumb+0x300/0x300 [ 43.138735] ? drm_getstats+0x20/0x20 [ 43.142544] ? cmp_ex_sort+0xc0/0xc0 [ 43.146540] ? __do_page_fault+0x180/0xd60 [ 43.150781] ? retint_kernel+0x2d/0x2d [ 43.154698] ? futex_exit_release+0x220/0x220 [ 43.159300] ? drm_getstats+0x20/0x20 [ 43.163102] do_vfs_ioctl+0xcdb/0x12e0 [ 43.167019] ? lock_downgrade+0x720/0x720 [ 43.171216] ? check_preemption_disabled+0x41/0x280 [ 43.176813] ? ioctl_preallocate+0x200/0x200 [ 43.181366] ? __fget+0x356/0x510 [ 43.184921] ? do_dup2+0x450/0x450 [ 43.188658] ? __se_sys_futex+0x298/0x3b0 [ 43.192947] ksys_ioctl+0x9b/0xc0 [ 43.196439] __x64_sys_ioctl+0x6f/0xb0 [ 43.200341] ? lockdep_hardirqs_on+0x3a8/0x5c0 [ 43.204929] do_syscall_64+0xf9/0x620 [ 43.208737] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 43.213947] RIP: 0033:0x44a4a9 [ 43.217152] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 00 00 90 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 [ 43.236159] RSP: 002b:00007fda1c08b308 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 43.244709] RAX: ffffffffffffffda RBX: 00000000004cb428 RCX: 000000000044a4a9 [ 43.252138] RDX: 00000000200000c0 RSI: 00000000c02064b2 RDI: 0000000000000004 [ 43.259428] RBP: 00000000004cb420 R08: 0000000000000000 R09: 0000000000000000 [ 43.266697] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004cb42c [ 43.273963] R13: 000000000049b07c R14: 6972642f7665642f R15: 0000000000022000 [ 43.281257] [ 43.282877] Allocated by task 10161: [ 43.286597] kmem_cache_alloc_trace+0x12f/0x380 [ 43.291265] __vgem_gem_create+0x44/0xf0 [ 43.295693] vgem_gem_dumb_create+0xcf/0x240 [ 43.300492] drm_mode_create_dumb+0x27c/0x300 [ 43.305080] drm_ioctl_kernel+0x208/0x2a0 [ 43.309240] drm_ioctl+0x507/0x9c0 [ 43.312868] do_vfs_ioctl+0xcdb/0x12e0 [ 43.316756] ksys_ioctl+0x9b/0xc0 [ 43.320274] __x64_sys_ioctl+0x6f/0xb0 [ 43.324358] do_syscall_64+0xf9/0x620 [ 43.328164] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 43.333361] [ 43.334993] Freed by task 10161: [ 43.338371] kfree+0xcc/0x210 [ 43.341492] drm_gem_object_free+0x91/0x1c0 [ 43.345975] drm_gem_object_put_unlocked+0xd1/0x180 [ 43.351221] vgem_gem_dumb_create+0x10c/0x240 [ 43.355737] drm_mode_create_dumb+0x27c/0x300 [ 43.360260] drm_ioctl_kernel+0x208/0x2a0 [ 43.364413] drm_ioctl+0x507/0x9c0 [ 43.367975] do_vfs_ioctl+0xcdb/0x12e0 [ 43.372037] ksys_ioctl+0x9b/0xc0 [ 43.375526] __x64_sys_ioctl+0x6f/0xb0 [ 43.379429] do_syscall_64+0xf9/0x620 [ 43.383239] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 43.388448] [ 43.390088] The buggy address belongs to the object at ffff888092fb1340 [ 43.390088] which belongs to the cache kmalloc-512 of size 512 [ 43.402917] The buggy address is located 256 bytes inside of [ 43.402917] 512-byte region [ffff888092fb1340, ffff888092fb1540) [ 43.414805] The buggy address belongs to the page: [ 43.419850] page:ffffea00024bec40 count:1 mapcount:0 mapping:ffff88813bff0940 index:0x0 [ 43.427989] flags: 0xfff00000000100(slab) [ 43.432156] raw: 00fff00000000100 ffffea0002a66748 ffff88813bff1748 ffff88813bff0940 [ 43.440129] raw: 0000000000000000 ffff888092fb10c0 0000000100000006 0000000000000000 [ 43.448120] page dumped because: kasan: bad access detected [ 43.453849] [ 43.455653] Memory state around the buggy address: [ 43.460832] ffff888092fb1300: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 43.468305] ffff888092fb1380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 43.475690] >ffff888092fb1400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 43.483053] ^ [ 43.488511] ffff888092fb1480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 43.495871] ffff888092fb1500: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 43.503587] ================================================================== [ 43.511159] Disabling lock debugging due to kernel taint [ 43.526276] Kernel panic - not syncing: panic_on_warn set ... [ 43.526276] [ 43.533747] CPU: 0 PID: 10161 Comm: syz-executor256 Tainted: G B 4.19.193-syzkaller #0 [ 43.543155] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.552520] Call Trace: [ 43.555134] dump_stack+0x1fc/0x2ef [ 43.558870] panic+0x26a/0x50e [ 43.562062] ? __warn_printk+0xf3/0xf3 [ 43.566151] ? preempt_schedule_common+0x45/0xc0 [ 43.571001] ? ___preempt_schedule+0x16/0x18 [ 43.575427] ? trace_hardirqs_on+0x55/0x210 [ 43.581287] kasan_end_report+0x43/0x49 [ 43.585368] kasan_report_error.cold+0xa7/0x1b9 [ 43.590098] ? vgem_gem_dumb_create+0x22c/0x240 [ 43.594798] __asan_report_load8_noabort+0x88/0x90 [ 43.599752] ? drm_gem_object_put_unlocked+0xd0/0x180 [ 43.605203] ? vgem_gem_dumb_create+0x22c/0x240 [ 43.609917] vgem_gem_dumb_create+0x22c/0x240 [ 43.614414] drm_mode_create_dumb+0x27c/0x300 [ 43.618919] drm_ioctl_kernel+0x208/0x2a0 [ 43.623081] ? drm_mode_create_dumb+0x300/0x300 [ 43.627767] ? drm_ioctl_permit+0x210/0x210 [ 43.632179] ? __might_fault+0x192/0x1d0 [ 43.636240] drm_ioctl+0x507/0x9c0 [ 43.639830] ? drm_mode_create_dumb+0x300/0x300 [ 43.644501] ? drm_getstats+0x20/0x20 [ 43.648320] ? cmp_ex_sort+0xc0/0xc0 [ 43.652081] ? __do_page_fault+0x180/0xd60 [ 43.656417] ? retint_kernel+0x2d/0x2d [ 43.660307] ? futex_exit_release+0x220/0x220 [ 43.664805] ? drm_getstats+0x20/0x20 [ 43.668609] do_vfs_ioctl+0xcdb/0x12e0 [ 43.672715] ? lock_downgrade+0x720/0x720 [ 43.676880] ? check_preemption_disabled+0x41/0x280 [ 43.681909] ? ioctl_preallocate+0x200/0x200 [ 43.686438] ? __fget+0x356/0x510 [ 43.689911] ? do_dup2+0x450/0x450 [ 43.693839] ? __se_sys_futex+0x298/0x3b0 [ 43.698133] ksys_ioctl+0x9b/0xc0 [ 43.701600] __x64_sys_ioctl+0x6f/0xb0 [ 43.705491] ? lockdep_hardirqs_on+0x3a8/0x5c0 [ 43.710077] do_syscall_64+0xf9/0x620 [ 43.714009] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 43.719240] RIP: 0033:0x44a4a9 [ 43.722429] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 00 00 90 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 [ 43.741425] RSP: 002b:00007fda1c08b308 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 43.749328] RAX: ffffffffffffffda RBX: 00000000004cb428 RCX: 000000000044a4a9 [ 43.756754] RDX: 00000000200000c0 RSI: 00000000c02064b2 RDI: 0000000000000004 [ 43.764031] RBP: 00000000004cb420 R08: 0000000000000000 R09: 0000000000000000 [ 43.771297] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004cb42c [ 43.778585] R13: 000000000049b07c R14: 6972642f7665642f R15: 0000000000022000 [ 43.786646] Kernel Offset: disabled [ 43.790286] Rebooting in 86400 seconds..