================================================================== 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 ffff888124fac8d8 by task syz.6.380/1429 CPU: 1 PID: 1429 Comm: syz.6.380 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 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:5613 netlink_rcv_skb+0x1e9/0x430 net/netlink/af_netlink.c:2508 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5640 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: 0033:0x7fee95eebb19 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:00007fee94901028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fee96172180 RCX: 00007fee95eebb19 RDX: 0000000020000000 RSI: 00002000000006c0 RDI: 0000000000000006 RBP: 00007fee95f83b70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fee96172218 R14: 00007fee96172180 R15: 00007ffda7aae278 Allocated by task 1429: 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:434 tcf_idr_create_from_flags+0x61/0x70 net/sched/act_api.c:492 tcf_gact_init+0x2e6/0x560 net/sched/act_gact.c:107 tcf_action_init_1+0x443/0x6d0 net/sched/act_api.c:1056 tcf_action_init+0x227/0x780 net/sched/act_api.c:1113 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:5613 netlink_rcv_skb+0x1e9/0x430 net/netlink/af_netlink.c:2508 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5640 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 unregister_sysctl_table+0x75/0x120 fs/proc/proc_sysctl.c:1722 unregister_net_sysctl_table+0x15/0x20 net/sysctl_net.c:127 ip4_frags_ns_ctl_unregister net/ipv4/ip_fragment.c:629 [inline] ipv4_frags_exit_net+0x60/0xa0 net/ipv4/ip_fragment.c:697 ops_exit_list net/core/net_namespace.c:185 [inline] cleanup_net+0x589/0xb80 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 ffff888124fac800 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 216 bytes inside of 256-byte region [ffff888124fac800, ffff888124fac900) The buggy address belongs to the page: page:ffffea000493eb00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x124fac head:ffffea000493eb00 order:1 compound_mapcount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 ffffea0004944180 0000000400000004 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 280, ts 25597609455, free_ts 25597497110 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] new_dir fs/proc/proc_sysctl.c:958 [inline] get_subdir fs/proc/proc_sysctl.c:1003 [inline] __register_sysctl_table+0xa35/0x1240 fs/proc/proc_sysctl.c:1352 register_net_sysctl+0x2c/0x40 net/sysctl_net.c:121 sysctl_route_net_init+0xf4/0x150 net/ipv4/route.c:3518 ops_init+0x2c0/0x470 net/core/net_namespace.c:144 setup_net+0x34f/0xae0 net/core/net_namespace.c:345 copy_net_ns+0x314/0x520 net/core/net_namespace.c:486 create_new_namespaces+0x3a8/0x650 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x120/0x170 kernel/nsproxy.c:231 ksys_unshare+0x4fa/0x820 kernel/fork.c:3156 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_pages_ok+0x80b/0x830 mm/page_alloc.c:1629 free_the_page mm/page_alloc.c:5445 [inline] __free_pages+0xd8/0x390 mm/page_alloc.c:5454 free_pages+0x82/0x90 mm/page_alloc.c:5465 __stack_depot_save+0x492/0x4c0 lib/stackdepot.c:359 kasan_save_stack mm/kasan/common.c:39 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:430 [inline] __kasan_slab_alloc+0xc9/0xe0 mm/kasan/common.c:463 kasan_slab_alloc include/linux/kasan.h:244 [inline] slab_post_alloc_hook+0x5d/0x2f0 mm/slab.h:580 slab_alloc_node mm/slub.c:2952 [inline] slab_alloc mm/slub.c:2960 [inline] kmem_cache_alloc+0x15a/0x2d0 mm/slub.c:2965 kmem_cache_zalloc include/linux/slab.h:657 [inline] __proc_create+0x376/0x8f0 fs/proc/generic.c:432 proc_create_reg+0x96/0x110 fs/proc/generic.c:559 proc_create_net_data+0x95/0x1a0 fs/proc/proc_net.c:110 fib_proc_init+0xc6/0x140 net/ipv4/fib_trie.c:2978 fib_net_init+0x1bb/0x2d0 net/ipv4/fib_frontend.c:1612 ops_init+0x2c0/0x470 net/core/net_namespace.c:144 setup_net+0x34f/0xae0 net/core/net_namespace.c:345 copy_net_ns+0x314/0x520 net/core/net_namespace.c:486 create_new_namespaces+0x3a8/0x650 kernel/nsproxy.c:110 Memory state around the buggy address: ffff888124fac780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888124fac800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888124fac880: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc ^ ffff888124fac900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888124fac980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 280, ts 25597609455, free_ts 25597497110 page last free stack trace: