syzbot

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BUG: KASAN: use-after-free in dev_xdp_mode net/core/dev.c:9197 [inline]
BUG: KASAN: use-after-free in dev_xdp_mode net/core/dev.c:9189 [inline]
BUG: KASAN: use-after-free in dev_xdp_detach_link net/core/dev.c:9451 [inline]
BUG: KASAN: use-after-free in bpf_xdp_link_release+0x4a2/0x4f0 net/core/dev.c:9471
Read of size 8 at addr ffff88805caa80c8 by task syz-executor.4/24768

CPU: 0 PID: 24768 Comm: syz-executor.4 Not tainted 5.12.0-rc4-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:232
 __kasan_report mm/kasan/report.c:399 [inline]
 kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416
 dev_xdp_mode net/core/dev.c:9197 [inline]
 dev_xdp_mode net/core/dev.c:9189 [inline]
 dev_xdp_detach_link net/core/dev.c:9451 [inline]
 bpf_xdp_link_release+0x4a2/0x4f0 net/core/dev.c:9471
 bpf_link_free+0xe6/0x1b0 kernel/bpf/syscall.c:2332
 bpf_link_put+0x161/0x1b0 kernel/bpf/syscall.c:2358
 bpf_link_release+0x33/0x40 kernel/bpf/syscall.c:2366
 __fput+0x288/0x920 fs/file_table.c:280
 task_work_run+0xdd/0x1a0 kernel/task_work.c:140
 exit_task_work include/linux/task_work.h:30 [inline]
 do_exit+0xbfc/0x2a60 kernel/exit.c:825
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x42c/0x2100 kernel/signal.c:2777
 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:789
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x466459
Code: Unable to access opcode bytes at RIP 0x46642f.
RSP: 002b:00007fd714baf188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 0000000020000080 RSI: 00000000000089a1 RDI: 000000000000000b
RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffeca61dcdf R14: 00007fd714baf300 R15: 0000000000022000

Allocated by task 8436:
 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:427 [inline]
 ____kasan_kmalloc mm/kasan/common.c:506 [inline]
 ____kasan_kmalloc mm/kasan/common.c:465 [inline]
 __kasan_kmalloc+0x99/0xc0 mm/kasan/common.c:515
 kmalloc_node include/linux/slab.h:577 [inline]
 kvmalloc_node+0xb4/0xf0 mm/util.c:587
 kvmalloc include/linux/mm.h:785 [inline]
 kvzalloc include/linux/mm.h:793 [inline]
 alloc_netdev_mqs+0x97/0xeb0 net/core/dev.c:10694
 rtnl_create_link+0x1a4/0xae0 net/core/rtnetlink.c:3171
 __rtnl_newlink+0xf72/0x1710 net/core/rtnetlink.c:3433
 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3491
 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5553
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2502
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:674
 __sys_sendto+0x21c/0x320 net/socket.c:1977
 __do_sys_sendto net/socket.c:1989 [inline]
 __se_sys_sendto net/socket.c:1985 [inline]
 __x64_sys_sendto+0xdd/0x1b0 net/socket.c:1985
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 24768:
 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+0xf5/0x130 mm/kasan/common.c:367
 kasan_slab_free include/linux/kasan.h:199 [inline]
 slab_free_hook mm/slub.c:1562 [inline]
 slab_free_freelist_hook+0x92/0x210 mm/slub.c:1600
 slab_free mm/slub.c:3161 [inline]
 kfree+0xe5/0x7f0 mm/slub.c:4213
 kvfree+0x42/0x50 mm/util.c:616
 device_release+0x9f/0x240 drivers/base/core.c:2108
 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
 netdev_run_todo+0x96a/0xdd0 net/core/dev.c:10504
 br_del_bridge+0xd2/0x110 net/bridge/br_if.c:488
 br_ioctl_deviceless_stub+0x28b/0x770 net/bridge/br_ioctl.c:375
 sock_ioctl+0x3e8/0x6a0 net/socket.c:1137
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 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
 insert_work+0x48/0x370 kernel/workqueue.c:1331
 __queue_work+0x5c1/0xf00 kernel/workqueue.c:1497
 queue_work_on+0xee/0x110 kernel/workqueue.c:1524
 queue_work include/linux/workqueue.h:507 [inline]
 schedule_work include/linux/workqueue.h:568 [inline]
 __rhashtable_remove_fast_one include/linux/rhashtable.h:1059 [inline]
 __rhashtable_remove_fast include/linux/rhashtable.h:1083 [inline]
 rhashtable_remove_fast include/linux/rhashtable.h:1112 [inline]
 fdb_delete+0x7f2/0x1150 net/bridge/br_fdb.c:205
 fdb_delete_local+0x5a6/0x700 net/bridge/br_fdb.c:243
 br_fdb_delete_by_port+0x248/0x340 net/bridge/br_fdb.c:422
 del_nbp+0x3e7/0xd40 net/bridge/br_if.c:347
 br_dev_delete+0x95/0x190 net/bridge/br_if.c:376
 br_del_bridge+0xc8/0x110 net/bridge/br_if.c:486
 br_ioctl_deviceless_stub+0x28b/0x770 net/bridge/br_ioctl.c:375
 sock_ioctl+0x3e8/0x6a0 net/socket.c:1137
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Second to 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
 insert_work+0x48/0x370 kernel/workqueue.c:1331
 __queue_work+0x5c1/0xf00 kernel/workqueue.c:1497
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1431
 expire_timers kernel/time/timer.c:1471 [inline]
 __run_timers.part.0+0x4a6/0xa50 kernel/time/timer.c:1745
 __run_timers kernel/time/timer.c:1726 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1758
 __do_softirq+0x29b/0x9f6 kernel/softirq.c:345

The buggy address belongs to the object at ffff88805caa8000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 200 bytes inside of
 8192-byte region [ffff88805caa8000, ffff88805caaa000)
The buggy address belongs to the page:
page:ffffea000172aa00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5caa8
head:ffffea000172aa00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010442280
raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88805caa7f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805caa8000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805caa8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff88805caa8100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805caa8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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