================================================================== BUG: KASAN: use-after-free in kobject_put+0x493/0x540 lib/kobject.c:749 Read of size 1 at addr ffff8880234ac4bc by task syz-executor123/27771 CPU: 1 PID: 27771 Comm: syz-executor123 Not tainted 5.13.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:436 kobject_put+0x493/0x540 lib/kobject.c:749 delete_partition+0xb9/0x180 block/partitions/core.c:294 bdev_del_partition+0xe5/0x100 block/partitions/core.c:481 blkpg_do_ioctl+0x2e8/0x340 block/ioctl.c:33 blkpg_ioctl block/ioctl.c:60 [inline] blkdev_ioctl+0x577/0x6d0 block/ioctl.c:550 block_ioctl+0xf9/0x140 fs/block_dev.c:1662 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x444309 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffed6876f78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000487062 RCX: 0000000000444309 RDX: 0000000020000240 RSI: 0000000000001269 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0023706f6f6c2f76 R09: 0000000000000001 R10: 000000000000001f R11: 0000000000000246 R12: 0000000000076392 R13: 00007ffed6876f8c R14: 00007ffed6876fa0 R15: 00007ffed6876f90 Allocated by task 27771: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:428 [inline] ____kasan_kmalloc mm/kasan/common.c:507 [inline] ____kasan_kmalloc mm/kasan/common.c:466 [inline] __kasan_kmalloc+0x9b/0xd0 mm/kasan/common.c:516 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:686 [inline] kobject_create lib/kobject.c:784 [inline] kobject_create_and_add+0x42/0xb0 lib/kobject.c:810 add_partition+0x5ee/0x910 block/partitions/core.c:394 bdev_add_partition+0xb6/0x130 block/partitions/core.c:459 blkpg_do_ioctl+0x2d0/0x340 block/ioctl.c:43 blkpg_ioctl block/ioctl.c:60 [inline] blkdev_ioctl+0x577/0x6d0 block/ioctl.c:550 block_ioctl+0xf9/0x140 fs/block_dev.c:1662 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 27775: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357 ____kasan_slab_free mm/kasan/common.c:360 [inline] ____kasan_slab_free mm/kasan/common.c:325 [inline] __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:368 kasan_slab_free include/linux/kasan.h:212 [inline] slab_free_hook mm/slub.c:1583 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1608 slab_free mm/slub.c:3168 [inline] kfree+0xe5/0x7f0 mm/slub.c:4212 kobject_cleanup lib/kobject.c:705 [inline] kobject_release lib/kobject.c:736 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1c8/0x540 lib/kobject.c:753 delete_partition+0xb9/0x180 block/partitions/core.c:294 bdev_del_partition+0xe5/0x100 block/partitions/core.c:481 blkpg_do_ioctl+0x2e8/0x340 block/ioctl.c:33 blkpg_ioctl block/ioctl.c:60 [inline] blkdev_ioctl+0x577/0x6d0 block/ioctl.c:550 block_ioctl+0xf9/0x140 fs/block_dev.c:1662 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae Last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:345 kvfree_call_rcu+0x74/0x8c0 kernel/rcu/tree.c:3597 sctp_inet6addr_event+0x387/0x800 net/sctp/ipv6.c:114 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 atomic_notifier_call_chain+0x8d/0x170 kernel/notifier.c:217 addrconf_ifdown.isra.0+0xa71/0x15b0 net/ipv6/addrconf.c:3821 addrconf_notify+0x55c/0x23e0 net/ipv6/addrconf.c:3631 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2121 call_netdevice_notifiers_extack net/core/dev.c:2133 [inline] call_netdevice_notifiers net/core/dev.c:2147 [inline] dev_close_many+0x2ff/0x620 net/core/dev.c:1722 unregister_netdevice_many+0x3ff/0x1790 net/core/dev.c:11002 default_device_exit_batch+0x2fa/0x3c0 net/core/dev.c:11555 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:178 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:595 process_one_work+0x98d/0x1600 kernel/workqueue.c:2276 worker_thread+0x64c/0x1120 kernel/workqueue.c:2422 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 The buggy address belongs to the object at ffff8880234ac480 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 60 bytes inside of 64-byte region [ffff8880234ac480, ffff8880234ac4c0) The buggy address belongs to the page: page:ffffea00008d2b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x234ac flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea000052bc00 0000001400000014 ffff888010041640 raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880234ac380: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff8880234ac400: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff8880234ac480: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff8880234ac500: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff8880234ac580: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ==================================================================