================================================================== BUG: KASAN: slab-use-after-free in tcf_action_destroy+0x17f/0x1b0 net/sched/act_api.c:1121 Read of size 8 at addr ffff888072828c00 by task kworker/u4:5/2416 CPU: 0 PID: 2416 Comm: kworker/u4:5 Not tainted 6.3.0-rc5-syzkaller-01262-g48b7ea1d22dd #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023 Workqueue: tc_filter_workqueue fl_destroy_filter_work Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:319 print_report mm/kasan/report.c:430 [inline] kasan_report+0x11c/0x130 mm/kasan/report.c:536 tcf_action_destroy+0x17f/0x1b0 net/sched/act_api.c:1121 tcf_exts_destroy+0xc5/0x160 net/sched/cls_api.c:3248 __fl_destroy_filter+0x1a/0x100 net/sched/cls_flower.c:418 process_one_work+0x991/0x15c0 kernel/workqueue.c:2390 worker_thread+0x669/0x1090 kernel/workqueue.c:2537 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Allocated by task 7397: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] ____kasan_kmalloc mm/kasan/common.c:333 [inline] __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:580 [inline] kmalloc_array include/linux/slab.h:635 [inline] kcalloc include/linux/slab.h:667 [inline] tcf_exts_init_ex+0xe4/0x5a0 net/sched/cls_api.c:3218 fl_change+0x56f/0x4ac0 net/sched/cls_flower.c:2237 tc_new_tfilter+0x97c/0x2290 net/sched/cls_api.c:2310 rtnetlink_rcv_msg+0x996/0xd50 net/core/rtnetlink.c:6379 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2575 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg+0xde/0x190 net/socket.c:747 ____sys_sendmsg+0x334/0x900 net/socket.c:2501 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2555 __sys_sendmmsg+0x18f/0x460 net/socket.c:2641 __do_sys_sendmmsg net/socket.c:2670 [inline] __se_sys_sendmmsg net/socket.c:2667 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2667 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 7397: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:521 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3787 [inline] __kmem_cache_free+0xaf/0x2d0 mm/slub.c:3800 tcf_exts_destroy+0xe5/0x160 net/sched/cls_api.c:3249 tcf_exts_init_ex net/sched/cls_api.c:3237 [inline] tcf_exts_init_ex+0x484/0x5a0 net/sched/cls_api.c:3205 fl_change+0x56f/0x4ac0 net/sched/cls_flower.c:2237 tc_new_tfilter+0x97c/0x2290 net/sched/cls_api.c:2310 rtnetlink_rcv_msg+0x996/0xd50 net/core/rtnetlink.c:6379 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2575 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg+0xde/0x190 net/socket.c:747 ____sys_sendmsg+0x334/0x900 net/socket.c:2501 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2555 __sys_sendmmsg+0x18f/0x460 net/socket.c:2641 __do_sys_sendmmsg net/socket.c:2670 [inline] __se_sys_sendmmsg net/socket.c:2667 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2667 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:491 kvfree_call_rcu+0x70/0xad0 kernel/rcu/tree.c:3316 drop_sysctl_table+0x3c2/0x4e0 fs/proc/proc_sysctl.c:1715 unregister_sysctl_table fs/proc/proc_sysctl.c:1753 [inline] unregister_sysctl_table+0xc4/0x190 fs/proc/proc_sysctl.c:1728 __addrconf_sysctl_unregister net/ipv6/addrconf.c:7118 [inline] addrconf_sysctl_unregister+0xee/0x1c0 net/ipv6/addrconf.c:7146 addrconf_ifdown.isra.0+0x1350/0x1940 net/ipv6/addrconf.c:3908 addrconf_notify+0x106/0x19f0 net/ipv6/addrconf.c:3678 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb9/0x130 net/core/dev.c:1935 call_netdevice_notifiers_extack net/core/dev.c:1973 [inline] call_netdevice_notifiers net/core/dev.c:1987 [inline] unregister_netdevice_many_notify+0x77c/0x1910 net/core/dev.c:10867 unregister_netdevice_many net/core/dev.c:10923 [inline] default_device_exit_batch+0x451/0x5b0 net/core/dev.c:11376 ops_exit_list+0x125/0x170 net/core/net_namespace.c:174 setup_net+0x7fb/0xc50 net/core/net_namespace.c:361 copy_net_ns+0x4ee/0x8e0 net/core/net_namespace.c:490 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:228 ksys_unshare+0x449/0x920 kernel/fork.c:3200 __do_sys_unshare kernel/fork.c:3271 [inline] __se_sys_unshare kernel/fork.c:3269 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:3269 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888072828c00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 0 bytes inside of freed 256-byte region [ffff888072828c00, ffff888072828d00) The buggy address belongs to the physical page: page:ffffea0001ca0a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x72828 head:ffffea0001ca0a00 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 ksm flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888012441b40 ffffea0001dbbf00 0000000000000007 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 6794, tgid 6792 (syz-executor.3), ts 1046565724513, free_ts 1046546913540 prep_new_page mm/page_alloc.c:2553 [inline] get_page_from_freelist+0x1190/0x2e20 mm/page_alloc.c:4326 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:5592 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2283 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x25f/0x390 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3193 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3292 __slab_alloc_node mm/slub.c:3345 [inline] slab_alloc_node mm/slub.c:3442 [inline] __kmem_cache_alloc_node+0x136/0x320 mm/slub.c:3491 __do_kmalloc_node mm/slab_common.c:966 [inline] __kmalloc+0x4e/0x190 mm/slab_common.c:980 kmalloc include/linux/slab.h:584 [inline] kzalloc include/linux/slab.h:720 [inline] new_dir fs/proc/proc_sysctl.c:971 [inline] get_subdir fs/proc/proc_sysctl.c:1015 [inline] __register_sysctl_table+0xbfd/0x1550 fs/proc/proc_sysctl.c:1372 mpls_net_init+0x183/0x240 net/mpls/af_mpls.c:2691 ops_init+0xb9/0x6b0 net/core/net_namespace.c:135 setup_net+0x5d1/0xc50 net/core/net_namespace.c:338 copy_net_ns+0x4ee/0x8e0 net/core/net_namespace.c:490 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:228 ksys_unshare+0x449/0x920 kernel/fork.c:3200 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1454 [inline] free_pcp_prepare+0x5d5/0xa50 mm/page_alloc.c:1504 free_unref_page_prepare mm/page_alloc.c:3388 [inline] free_unref_page+0x1d/0x490 mm/page_alloc.c:3483 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2637 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x192/0x220 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x63/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook mm/slab.h:769 [inline] slab_alloc_node mm/slub.c:3452 [inline] slab_alloc mm/slub.c:3460 [inline] __kmem_cache_alloc_lru mm/slub.c:3467 [inline] kmem_cache_alloc+0x17c/0x3b0 mm/slub.c:3476 kmem_cache_zalloc include/linux/slab.h:710 [inline] __proc_create+0x2b3/0x8b0 fs/proc/generic.c:426 proc_create_reg+0xb6/0x180 fs/proc/generic.c:553 proc_create_net_data+0x90/0x1b0 fs/proc/proc_net.c:120 raw_init_net+0x59/0x80 net/ipv4/raw.c:1060 ops_init+0xb9/0x6b0 net/core/net_namespace.c:135 setup_net+0x5d1/0xc50 net/core/net_namespace.c:338 copy_net_ns+0x4ee/0x8e0 net/core/net_namespace.c:490 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:228 Memory state around the buggy address: ffff888072828b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888072828b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888072828c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888072828c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888072828d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================