================================================================== BUG: KASAN: slab-out-of-bounds in is_tcf_tunnel_set include/net/tc_act/tc_tunnel_key.h:33 [inline] BUG: KASAN: slab-out-of-bounds in tc_setup_flow_action+0x88e/0x3160 net/sched/cls_api.c:3640 Read of size 8 at addr ffff8881212b3cd8 by task syz.4.1192/4876 CPU: 0 PID: 4876 Comm: syz.4.1192 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:77 dump_stack_lvl+0x1a7/0x208 lib/dump_stack.c:118 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0x100/0x140 mm/kasan/report.c:452 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309 is_tcf_tunnel_set include/net/tc_act/tc_tunnel_key.h:33 [inline] tc_setup_flow_action+0x88e/0x3160 net/sched/cls_api.c:3640 mall_replace_hw_filter+0x2db/0x8c0 net/sched/cls_matchall.c:100 mall_change+0x546/0x770 net/sched/cls_matchall.c:236 tc_new_tfilter+0x1487/0x1ab0 net/sched/cls_api.c:2134 rtnetlink_rcv_msg+0x811/0xca0 net/core/rtnetlink.c:5605 netlink_rcv_skb+0x1e9/0x430 net/netlink/af_netlink.c:2508 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5632 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x86c/0xa30 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x949/0xb70 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] __sock_sendmsg net/socket.c:664 [inline] ____sys_sendmsg+0x5be/0x8f0 net/socket.c:2377 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2431 __sys_sendmsg net/socket.c:2460 [inline] __do_sys_sendmsg net/socket.c:2469 [inline] __se_sys_sendmsg net/socket.c:2467 [inline] __x64_sys_sendmsg+0x201/0x2d0 net/socket.c:2467 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f12bf379e99 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f12bdd91028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f12bf602180 RCX: 00007f12bf379e99 RDX: 0000000020000000 RSI: 0000200000000580 RDI: 0000000000000007 RBP: 00007f12bf40feaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f12bf602218 R14: 00007f12bf602180 R15: 00007ffc7c247a38 Allocated by task 4876: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:430 [inline] ____kasan_kmalloc mm/kasan/common.c:509 [inline] __kasan_kmalloc+0xd4/0x100 mm/kasan/common.c:518 kasan_kmalloc include/linux/kasan.h:254 [inline] __kmalloc+0x19f/0x330 mm/slub.c:4038 kmalloc include/linux/slab.h:560 [inline] kzalloc include/linux/slab.h:667 [inline] tcf_idr_create+0x5f/0x790 net/sched/act_api.c:425 tcf_idr_create_from_flags+0x61/0x70 net/sched/act_api.c:483 tcf_gact_init+0x2e6/0x560 net/sched/act_gact.c:102 tcf_action_init_1+0x443/0x6d0 net/sched/act_api.c:1047 tcf_action_init+0x227/0x780 net/sched/act_api.c:1104 tcf_exts_validate+0x23c/0x540 net/sched/cls_api.c:3087 mall_set_parms+0x4a/0x450 net/sched/cls_matchall.c:171 mall_change+0x47a/0x770 net/sched/cls_matchall.c:230 tc_new_tfilter+0x1487/0x1ab0 net/sched/cls_api.c:2134 rtnetlink_rcv_msg+0x811/0xca0 net/core/rtnetlink.c:5605 netlink_rcv_skb+0x1e9/0x430 net/netlink/af_netlink.c:2508 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5632 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x86c/0xa30 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x949/0xb70 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] __sock_sendmsg net/socket.c:664 [inline] ____sys_sendmsg+0x5be/0x8f0 net/socket.c:2377 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2431 __sys_sendmsg net/socket.c:2460 [inline] __do_sys_sendmsg net/socket.c:2469 [inline] __se_sys_sendmsg net/socket.c:2467 [inline] __x64_sys_sendmsg+0x201/0x2d0 net/socket.c:2467 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 kvfree_call_rcu+0x117/0x670 kernel/rcu/tree.c:3539 drop_sysctl_table+0x2f5/0x430 fs/proc/proc_sysctl.c:1684 drop_sysctl_table+0x2e4/0x430 fs/proc/proc_sysctl.c:1687 unregister_sysctl_table+0x75/0x120 fs/proc/proc_sysctl.c:1722 unregister_net_sysctl_table+0x15/0x20 net/sysctl_net.c:127 __addrconf_sysctl_unregister net/ipv6/addrconf.c:7091 [inline] addrconf_sysctl_unregister net/ipv6/addrconf.c:7119 [inline] addrconf_ifdown+0x1597/0x1890 net/ipv6/addrconf.c:3939 addrconf_notify+0x3bd/0xea0 net/ipv6/addrconf.c:-1 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2052 [inline] call_netdevice_notifiers_extack net/core/dev.c:2064 [inline] call_netdevice_notifiers net/core/dev.c:2078 [inline] unregister_netdevice_many+0x100e/0x19f0 net/core/dev.c:10778 default_device_exit_batch+0x35e/0x3c0 net/core/dev.c:11298 ops_exit_list net/core/net_namespace.c:190 [inline] cleanup_net+0x5fe/0xb80 net/core/net_namespace.c:609 process_one_work+0x6fd/0xbc0 kernel/workqueue.c:2301 worker_thread+0xa8e/0x13c0 kernel/workqueue.c:2447 kthread+0x324/0x3b0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Second to last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 __call_rcu kernel/rcu/tree.c:2980 [inline] call_rcu+0x11a/0x1090 kernel/rcu/tree.c:3054 free_fib_info net/ipv4/fib_semantics.c:255 [inline] fib_info_put include/net/ip_fib.h:531 [inline] fib_release_info+0x526/0x600 net/ipv4/fib_semantics.c:281 fib_table_flush+0xb5a/0x1340 net/ipv4/fib_trie.c:2022 fib_flush net/ipv4/fib_frontend.c:194 [inline] fib_disable_ip net/ipv4/fib_frontend.c:1431 [inline] fib_netdev_event+0x3d8/0x5b0 net/ipv4/fib_frontend.c:1500 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2052 [inline] call_netdevice_notifiers_extack net/core/dev.c:2064 [inline] call_netdevice_notifiers net/core/dev.c:2078 [inline] dev_close_many+0x328/0x4d0 net/core/dev.c:1653 unregister_netdevice_many+0x477/0x19f0 net/core/dev.c:10755 default_device_exit_batch+0x35e/0x3c0 net/core/dev.c:11298 ops_exit_list net/core/net_namespace.c:190 [inline] cleanup_net+0x5fe/0xb80 net/core/net_namespace.c:609 process_one_work+0x6fd/0xbc0 kernel/workqueue.c:2301 worker_thread+0xa8e/0x13c0 kernel/workqueue.c:2447 kthread+0x324/0x3b0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the object at ffff8881212b3c00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 216 bytes inside of 256-byte region [ffff8881212b3c00, ffff8881212b3d00) The buggy address belongs to the page: page:ffffea000484ac80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1212b2 head:ffffea000484ac80 order:1 compound_mapcount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 ffffea0004640e80 0000000400000003 ffff888100043200 raw: 0000000000000000 0000000080100010 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 2924, ts 137356711726, free_ts 135395667891 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x176/0x190 mm/page_alloc.c:2462 get_page_from_freelist+0x225f/0x23f0 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x29a/0x640 mm/page_alloc.c:5384 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1813 [inline] new_slab+0x84/0x3f0 mm/slub.c:1874 new_slab_objects mm/slub.c:2632 [inline] ___slab_alloc+0x2f8/0x4c0 mm/slub.c:2796 __slab_alloc+0x63/0xa0 mm/slub.c:2836 slab_alloc_node mm/slub.c:2918 [inline] slab_alloc mm/slub.c:2960 [inline] __kmalloc+0x1f9/0x330 mm/slub.c:4034 kmalloc include/linux/slab.h:560 [inline] kzalloc include/linux/slab.h:667 [inline] fib_create_info+0x8eb/0x1ed0 net/ipv4/fib_semantics.c:1477 fib_table_insert+0xc2/0x1d50 net/ipv4/fib_trie.c:1170 fib_magic net/ipv4/fib_frontend.c:1107 [inline] fib_add_ifaddr+0x360/0xf90 net/ipv4/fib_frontend.c:1129 fib_netdev_event+0x22e/0x5b0 net/ipv4/fib_frontend.c:1491 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2052 [inline] call_netdevice_notifiers_extack net/core/dev.c:2064 [inline] call_netdevice_notifiers net/core/dev.c:2078 [inline] __dev_notify_flags+0x2f4/0x5b0 net/core/dev.c:8583 dev_change_flags+0xe3/0x1a0 net/core/dev.c:8621 do_setlink+0xb19/0x29a0 net/core/rtnetlink.c:2736 __rtnl_newlink net/core/rtnetlink.c:3414 [inline] rtnl_newlink+0x13e6/0x1830 net/core/rtnetlink.c:3534 page last free stack trace: reset_page_owner include/linux/page_owner.h:28 [inline] free_pages_prepare mm/page_alloc.c:1349 [inline] free_pcp_prepare mm/page_alloc.c:1421 [inline] free_unref_page_prepare+0x2b7/0x2d0 mm/page_alloc.c:3336 free_unref_page mm/page_alloc.c:3391 [inline] free_the_page mm/page_alloc.c:5443 [inline] __free_pages+0x146/0x390 mm/page_alloc.c:5454 __vunmap+0x801/0x980 mm/vmalloc.c:2307 __vfree mm/vmalloc.c:2356 [inline] vfree+0x61/0x90 mm/vmalloc.c:2387 kcov_put kernel/kcov.c:408 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:510 __fput+0x2dc/0x730 fs/file_table.c:281 ____fput+0x15/0x20 fs/file_table.c:314 task_work_run+0x127/0x190 kernel/task_work.c:189 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xa7c/0x24e0 kernel/exit.c:873 do_group_exit+0x149/0x310 kernel/exit.c:987 __do_sys_exit_group kernel/exit.c:998 [inline] __se_sys_exit_group kernel/exit.c:996 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:996 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb Memory state around the buggy address: ffff8881212b3b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881212b3c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881212b3c80: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc ^ ffff8881212b3d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881212b3d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc 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