Warning: Permanently added '10.128.0.198' (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 syzkaller login: [ 528.093473][ T6982] ================================================================== [ 528.101801][ T6982] BUG: KASAN: use-after-free in kobject_put+0x245/0x2c0 [ 528.109695][ T6982] Read of size 1 at addr ffff8880a384e9bc by task syz-executor027/6982 [ 528.117921][ T6982] [ 528.120252][ T6982] CPU: 0 PID: 6982 Comm: syz-executor027 Not tainted 5.9.0-rc2-syzkaller #0 [ 528.128912][ T6982] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 528.139480][ T6982] Call Trace: [ 528.142794][ T6982] dump_stack+0x1d6/0x29e [ 528.147235][ T6982] print_address_description+0x66/0x620 [ 528.152899][ T6982] ? printk+0x62/0x83 [ 528.156996][ T6982] ? _raw_spin_lock_irqsave+0x84/0xd0 [ 528.162373][ T6982] ? vprintk_emit+0x2f0/0x370 [ 528.167082][ T6982] kasan_report+0x132/0x1d0 [ 528.171589][ T6982] ? kobject_put+0x245/0x2c0 [ 528.176181][ T6982] kobject_put+0x245/0x2c0 [ 528.180673][ T6982] bdev_del_partition+0x26a/0x380 [ 528.186665][ T6982] blkpg_do_ioctl+0x12b/0x2e0 [ 528.191363][ T6982] blkdev_ioctl+0x352/0x5d0 [ 528.195956][ T6982] block_ioctl+0xbc/0x100 [ 528.200293][ T6982] ? blkdev_iopoll+0xf0/0xf0 [ 528.204961][ T6982] __se_sys_ioctl+0xfb/0x170 [ 528.209617][ T6982] do_syscall_64+0x31/0x70 [ 528.214021][ T6982] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 528.220020][ T6982] RIP: 0033:0x446959 [ 528.223898][ T6982] Code: e8 0c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 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 db 06 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 528.243513][ T6982] RSP: 002b:00007f4a7a555d98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 528.251903][ T6982] RAX: ffffffffffffffda RBX: 00000000006dbc38 RCX: 0000000000446959 [ 528.259852][ T6982] RDX: 0000000020000000 RSI: 0000000000001269 RDI: 0000000000000005 [ 528.267818][ T6982] RBP: 00000000006dbc30 R08: 00007f4a7a556700 R09: 0000000000000000 [ 528.275765][ T6982] R10: 00007f4a7a556700 R11: 0000000000000246 R12: 00000000006dbc3c [ 528.283715][ T6982] R13: 00000000000000a9 R14: 00b747111e42e3ec R15: 02ba2b7a04b8ac00 [ 528.291671][ T6982] [ 528.293985][ T6982] Allocated by task 6977: [ 528.298343][ T6982] __kasan_kmalloc+0x100/0x130 [ 528.303086][ T6982] kmem_cache_alloc_trace+0x1e4/0x2e0 [ 528.308456][ T6982] kobject_create_and_add+0x57/0x240 [ 528.313719][ T6982] add_partition+0x884/0xcb0 [ 528.318329][ T6982] bdev_add_partition+0x1c9/0x230 [ 528.323350][ T6982] blkpg_do_ioctl+0x295/0x2e0 [ 528.328039][ T6982] blkdev_ioctl+0x352/0x5d0 [ 528.332517][ T6982] block_ioctl+0xbc/0x100 [ 528.336840][ T6982] __se_sys_ioctl+0xfb/0x170 [ 528.341405][ T6982] do_syscall_64+0x31/0x70 [ 528.345796][ T6982] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 528.351658][ T6982] [ 528.353962][ T6982] Freed by task 6979: [ 528.357920][ T6982] kasan_set_track+0x3d/0x70 [ 528.362501][ T6982] kasan_set_free_info+0x17/0x30 [ 528.367414][ T6982] __kasan_slab_free+0xdd/0x110 [ 528.372236][ T6982] kfree+0x113/0x200 [ 528.376105][ T6982] kobject_put+0x1a0/0x2c0 [ 528.380508][ T6982] bdev_del_partition+0x26a/0x380 [ 528.385521][ T6982] blkpg_do_ioctl+0x12b/0x2e0 [ 528.390170][ T6982] blkdev_ioctl+0x352/0x5d0 [ 528.394657][ T6982] block_ioctl+0xbc/0x100 [ 528.398978][ T6982] __se_sys_ioctl+0xfb/0x170 [ 528.403561][ T6982] do_syscall_64+0x31/0x70 [ 528.407954][ T6982] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 528.413815][ T6982] [ 528.416120][ T6982] The buggy address belongs to the object at ffff8880a384e980 [ 528.416120][ T6982] which belongs to the cache kmalloc-64 of size 64 [ 528.429976][ T6982] The buggy address is located 60 bytes inside of [ 528.429976][ T6982] 64-byte region [ffff8880a384e980, ffff8880a384e9c0) [ 528.443055][ T6982] The buggy address belongs to the page: [ 528.448676][ T6982] page:00000000f601aef4 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xa384e [ 528.458820][ T6982] flags: 0xfffe0000000200(slab) [ 528.463709][ T6982] raw: 00fffe0000000200 ffffea000263b548 ffffea00029bbac8 ffff8880aa440200 [ 528.472317][ T6982] raw: 0000000000000000 ffff8880a384e000 0000000100000020 0000000000000000 [ 528.480871][ T6982] page dumped because: kasan: bad access detected [ 528.487310][ T6982] [ 528.489613][ T6982] Memory state around the buggy address: [ 528.495342][ T6982] ffff8880a384e880: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc [ 528.503386][ T6982] ffff8880a384e900: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc [ 528.511454][ T6982] >ffff8880a384e980: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 528.520199][ T6982] ^ [ 528.526092][ T6982] ffff8880a384ea00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc [ 528.541631][ T6982] ffff8880a384ea80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc [ 528.549673][ T6982] ================================================================== [ 528.557724][ T6982] Disabling lock debugging due to kernel taint [ 528.575285][ T6982] Kernel panic - not syncing: panic_on_warn set ... [ 528.581922][ T6982] CPU: 0 PID: 6982 Comm: syz-executor027 Tainted: G B 5.9.0-rc2-syzkaller #0 [ 528.591970][ T6982] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 528.602010][ T6982] Call Trace: [ 528.605279][ T6982] dump_stack+0x1d6/0x29e [ 528.609700][ T6982] panic+0x2c0/0x800 [ 528.613635][ T6982] ? trace_hardirqs_on+0x30/0x80 [ 528.618561][ T6982] kasan_report+0x1c9/0x1d0 [ 528.623050][ T6982] ? kobject_put+0x245/0x2c0 [ 528.627635][ T6982] kobject_put+0x245/0x2c0 [ 528.632038][ T6982] bdev_del_partition+0x26a/0x380 [ 528.637044][ T6982] blkpg_do_ioctl+0x12b/0x2e0 [ 528.641706][ T6982] blkdev_ioctl+0x352/0x5d0 [ 528.646205][ T6982] block_ioctl+0xbc/0x100 [ 528.650516][ T6982] ? blkdev_iopoll+0xf0/0xf0 [ 528.655094][ T6982] __se_sys_ioctl+0xfb/0x170 [ 528.659674][ T6982] do_syscall_64+0x31/0x70 [ 528.664079][ T6982] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 528.669967][ T6982] RIP: 0033:0x446959 [ 528.673833][ T6982] Code: e8 0c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 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 db 06 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 528.693411][ T6982] RSP: 002b:00007f4a7a555d98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 528.701796][ T6982] RAX: ffffffffffffffda RBX: 00000000006dbc38 RCX: 0000000000446959 [ 528.709747][ T6982] RDX: 0000000020000000 RSI: 0000000000001269 RDI: 0000000000000005 [ 528.717722][ T6982] RBP: 00000000006dbc30 R08: 00007f4a7a556700 R09: 0000000000000000 [ 528.725673][ T6982] R10: 00007f4a7a556700 R11: 0000000000000246 R12: 00000000006dbc3c [ 528.733704][ T6982] R13: 00000000000000a9 R14: 00b747111e42e3ec R15: 02ba2b7a04b8ac00 [ 528.742720][ T6982] Kernel Offset: disabled [ 528.747045][ T6982] Rebooting in 86400 seconds..