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BUG: KASAN: use-after-free in prog_list_prog kernel/bpf/cgroup.c:174 [inline]
BUG: KASAN: use-after-free in prog_list_length kernel/bpf/cgroup.c:187 [inline]
BUG: KASAN: use-after-free in compute_effective_progs+0x1d3/0x6e0 kernel/bpf/cgroup.c:240
Read of size 8 at addr ffff88811c2de218 by task syz-executor.4/13389

CPU: 0 PID: 13389 Comm: syz-executor.4 Tainted: G        W         5.10.109-syzkaller-00693-g414e6c8e941c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118
 print_address_description+0x8d/0x3d0 mm/kasan/report.c:233
 __kasan_report+0x142/0x220 mm/kasan/report.c:419
 kasan_report+0x51/0x70 mm/kasan/report.c:436
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309
 prog_list_prog kernel/bpf/cgroup.c:174 [inline]
 prog_list_length kernel/bpf/cgroup.c:187 [inline]
 compute_effective_progs+0x1d3/0x6e0 kernel/bpf/cgroup.c:240
 update_effective_progs+0x79/0x310 kernel/bpf/cgroup.c:343
 __cgroup_bpf_detach+0x312/0x570 kernel/bpf/cgroup.c:689
 bpf_cgroup_link_release+0x94/0x260 kernel/bpf/cgroup.c:833
 bpf_link_free kernel/bpf/syscall.c:2350 [inline]
 bpf_link_put+0x1e9/0x270 kernel/bpf/syscall.c:2376
 bpf_link_release+0x3b/0x40 kernel/bpf/syscall.c:2384
 __fput+0x348/0x7d0 fs/file_table.c:281
 ____fput+0x15/0x20 fs/file_table.c:314
 task_work_run+0x147/0x1b0 kernel/task_work.c:154
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
 exit_to_user_mode_prepare+0xc3/0xe0 kernel/entry/common.c:191
 syscall_exit_to_user_mode+0x24/0x40 kernel/entry/common.c:266
 do_syscall_64+0x3d/0x70 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f3a48506c8b
Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44
RSP: 002b:00007ffe1da08300 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000015 RCX: 00007f3a48506c8b
RDX: 0000000000000000 RSI: 0000001b33421798 RDI: 0000000000000014
RBP: 00007f3a48668960 R08: 0000000000000000 R09: 00000000eb3bfc5d
R10: 0000000000000000 R11: 0000000000000293 R12: 00000000000ecb85
R13: 00007ffe1da08400 R14: 00007ffe1da08420 R15: 0000000000000032

Allocated by task 13390:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:428 [inline]
 ____kasan_kmalloc+0xdc/0x110 mm/kasan/common.c:507
 __kasan_kmalloc+0x9/0x10 mm/kasan/common.c:516
 kasan_kmalloc include/linux/kasan.h:269 [inline]
 kmem_cache_alloc_trace+0x210/0x3a0 mm/slub.c:2983
 kmalloc include/linux/slab.h:552 [inline]
 kzalloc include/linux/slab.h:664 [inline]
 cgroup_bpf_link_attach+0x12e/0x4a0 kernel/bpf/cgroup.c:918
 link_create kernel/bpf/syscall.c:4092 [inline]
 __do_sys_bpf+0xab8e/0x116b0 kernel/bpf/syscall.c:4497
 __se_sys_bpf kernel/bpf/syscall.c:4383 [inline]
 __x64_sys_bpf+0x7a/0x90 kernel/bpf/syscall.c:4383
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 13390:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:357
 ____kasan_slab_free+0x133/0x170 mm/kasan/common.c:360
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:368
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:1604 [inline]
 slab_free_freelist_hook+0xcc/0x1a0 mm/slub.c:1630
 slab_free mm/slub.c:3212 [inline]
 kfree+0xd5/0x320 mm/slub.c:4200
 bpf_cgroup_link_dealloc+0x15/0x20 kernel/bpf/cgroup.c:849
 bpf_link_free kernel/bpf/syscall.c:2354 [inline]
 bpf_link_put+0x243/0x270 kernel/bpf/syscall.c:2376
 bpf_link_release+0x3b/0x40 kernel/bpf/syscall.c:2384
 __fput+0x348/0x7d0 fs/file_table.c:281
 ____fput+0x15/0x20 fs/file_table.c:314
 task_work_run+0x147/0x1b0 kernel/task_work.c:154
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
 exit_to_user_mode_prepare+0xc3/0xe0 kernel/entry/common.c:191
 syscall_exit_to_user_mode+0x24/0x40 kernel/entry/common.c:266
 do_syscall_64+0x3d/0x70 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xd3/0xf0 mm/kasan/generic.c:345
 insert_work+0x56/0x330 kernel/workqueue.c:1348
 __queue_work+0x951/0xda0 kernel/workqueue.c:1514
 queue_work_on+0xef/0x150 kernel/workqueue.c:1541
 queue_work include/linux/workqueue.h:513 [inline]
 schedule_work include/linux/workqueue.h:574 [inline]
 nf_nat_masq_schedule+0x49a/0x5b0 net/netfilter/nf_nat_masquerade.c:125
 masq_device_event+0xa2/0xd0 net/netfilter/nf_nat_masquerade.c:157
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0x8e/0xf0 kernel/notifier.c:410
 __dev_notify_flags+0x306/0x5e0 net/core/dev.c:2054
 dev_change_flags+0xec/0x190 net/core/dev.c:8568
 do_setlink+0xd2f/0x4190 net/core/rtnetlink.c:2709
 rtnl_group_changelink net/core/rtnetlink.c:3228 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3384 [inline]
 rtnl_newlink+0x1132/0x1dc0 net/core/rtnetlink.c:3505
 rtnetlink_rcv_msg+0xbae/0xd70 net/core/rtnetlink.c:5571
 netlink_rcv_skb+0x200/0x470 net/netlink/af_netlink.c:2507
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5589
 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
 netlink_unicast+0x814/0x9f0 net/netlink/af_netlink.c:1337
 netlink_sendmsg+0xb47/0xe60 net/netlink/af_netlink.c:1932
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 ____sys_sendmsg+0x5b9/0x910 net/socket.c:2343
 ___sys_sendmsg net/socket.c:2397 [inline]
 __sys_sendmsg+0x384/0x470 net/socket.c:2430
 __do_sys_sendmsg net/socket.c:2439 [inline]
 __se_sys_sendmsg net/socket.c:2437 [inline]
 __x64_sys_sendmsg+0x7f/0x90 net/socket.c:2437
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff88811c2de200
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
 96-byte region [ffff88811c2de200, ffff88811c2de260)
The buggy address belongs to the page:
page:ffffea000470b780 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11c2de
flags: 0x8000000000000200(slab)
raw: 8000000000000200 dead000000000100 dead000000000122 ffff888100043680
raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 297, ts 16130895489, free_ts 0
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2385 [inline]
 prep_new_page mm/page_alloc.c:2391 [inline]
 get_page_from_freelist+0xa74/0xa90 mm/page_alloc.c:4063
 __alloc_pages_nodemask+0x3c8/0x820 mm/page_alloc.c:5113
 alloc_slab_page mm/slub.c:1815 [inline]
 allocate_slab+0x6b/0x350 mm/slub.c:1817
 new_slab mm/slub.c:1878 [inline]
 new_slab_objects mm/slub.c:2637 [inline]
 ___slab_alloc+0x143/0x2f0 mm/slub.c:2800
 __slab_alloc mm/slub.c:2840 [inline]
 slab_alloc_node mm/slub.c:2922 [inline]
 slab_alloc mm/slub.c:2964 [inline]
 kmem_cache_alloc_trace+0x278/0x3a0 mm/slub.c:2981
 kmem_cache_alloc_node_trace include/linux/slab.h:440 [inline]
 kmalloc_node include/linux/slab.h:570 [inline]
 kzalloc_node include/linux/slab.h:675 [inline]
 __get_vm_area_node+0x134/0x200 mm/vmalloc.c:2077
 __vmalloc_node_range+0xd8/0x750 mm/vmalloc.c:2560
 alloc_thread_stack_node kernel/fork.c:250 [inline]
 dup_task_struct+0x6e6/0xde0 kernel/fork.c:899
 copy_process+0x67a/0x5350 kernel/fork.c:1992
 kernel_clone+0x21f/0x9a0 kernel/fork.c:2523
 __do_sys_clone kernel/fork.c:2642 [inline]
 __se_sys_clone kernel/fork.c:2626 [inline]
 __x64_sys_clone+0x258/0x2d0 kernel/fork.c:2626
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88811c2de100: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
 ffff88811c2de180: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
>ffff88811c2de200: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                            ^
 ffff88811c2de280: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff88811c2de300: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
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