================================================================== BUG: KASAN: use-after-free in flow_block_cb_is_busy net/core/flow_offload.c:314 [inline] BUG: KASAN: use-after-free in flow_block_cb_setup_simple+0x1c8/0x740 net/core/flow_offload.c:339 Read of size 8 at addr ffff88807ed61620 by task syz.2.661/7766 CPU: 0 PID: 7766 Comm: syz.2.661 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 flow_block_cb_is_busy net/core/flow_offload.c:314 [inline] flow_block_cb_setup_simple+0x1c8/0x740 net/core/flow_offload.c:339 nft_block_offload_cmd net/netfilter/nf_tables_offload.c:392 [inline] nft_chain_offload_cmd+0x278/0x630 net/netfilter/nf_tables_offload.c:446 nft_flow_block_chain net/netfilter/nf_tables_offload.c:466 [inline] nft_flow_offload_chain net/netfilter/nf_tables_offload.c:505 [inline] nft_flow_rule_offload_commit+0x640/0x18c0 net/netfilter/nf_tables_offload.c:576 nf_tables_commit+0x585/0x74e0 net/netfilter/nf_tables_api.c:9698 nfnetlink_rcv_batch net/netfilter/nfnetlink.c:569 [inline] nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:639 [inline] nfnetlink_rcv+0x18b6/0x2170 net/netfilter/nfnetlink.c:657 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x89e/0xbc0 net/netlink/af_netlink.c:1872 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x59b/0x970 net/socket.c:2519 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573 __sys_sendmsg net/socket.c:2602 [inline] __do_sys_sendmsg net/socket.c:2611 [inline] __se_sys_sendmsg+0x19e/0x270 net/socket.c:2609 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f076fb8efc9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f07709f5038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f076fde6090 RCX: 00007f076fb8efc9 RDX: 0000000000000004 RSI: 000020000000c2c0 RDI: 0000000000000009 RBP: 00007f076fc11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f076fde6128 R14: 00007f076fde6090 R15: 00007fff25386998 Allocated by task 7704: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] flow_block_cb_alloc net/core/flow_offload.c:253 [inline] flow_block_cb_setup_simple+0x29d/0x740 net/core/flow_offload.c:342 nft_block_offload_cmd net/netfilter/nf_tables_offload.c:392 [inline] nft_chain_offload_cmd+0x278/0x630 net/netfilter/nf_tables_offload.c:446 nft_flow_block_chain net/netfilter/nf_tables_offload.c:466 [inline] nft_flow_offload_chain net/netfilter/nf_tables_offload.c:505 [inline] nft_flow_rule_offload_commit+0x640/0x18c0 net/netfilter/nf_tables_offload.c:576 nf_tables_commit+0x585/0x74e0 net/netfilter/nf_tables_api.c:9698 nfnetlink_rcv_batch net/netfilter/nfnetlink.c:569 [inline] nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:639 [inline] nfnetlink_rcv+0x18b6/0x2170 net/netfilter/nfnetlink.c:657 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x89e/0xbc0 net/netlink/af_netlink.c:1872 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x59b/0x970 net/socket.c:2519 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573 __sys_sendmsg net/socket.c:2602 [inline] __do_sys_sendmsg net/socket.c:2611 [inline] __se_sys_sendmsg+0x19e/0x270 net/socket.c:2609 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 7704: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700 nft_flow_offload_unbind+0x3bc/0x430 net/netfilter/nf_tables_offload.c:339 nft_chain_offload_cmd+0x416/0x630 net/netfilter/nf_tables_offload.c:-1 nft_flow_block_chain net/netfilter/nf_tables_offload.c:466 [inline] nft_flow_offload_chain net/netfilter/nf_tables_offload.c:505 [inline] nft_flow_rule_offload_commit+0x4d2/0x18c0 net/netfilter/nf_tables_offload.c:584 nf_tables_commit+0x585/0x74e0 net/netfilter/nf_tables_api.c:9698 nfnetlink_rcv_batch net/netfilter/nfnetlink.c:569 [inline] nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:639 [inline] nfnetlink_rcv+0x18b6/0x2170 net/netfilter/nfnetlink.c:657 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x89e/0xbc0 net/netlink/af_netlink.c:1872 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x59b/0x970 net/socket.c:2519 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573 __sys_sendmsg net/socket.c:2602 [inline] __do_sys_sendmsg net/socket.c:2611 [inline] __se_sys_sendmsg+0x19e/0x270 net/socket.c:2609 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88807ed61600 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 32 bytes inside of 192-byte region [ffff88807ed61600, ffff88807ed616c0) The buggy address belongs to the physical page: page:ffffea0001fb5840 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ed61 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 dead000000000001 ffff888017441a00 raw: 0000000000000000 0000000000100010 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 6943, tgid 6943 (dhcpcd-run-hook), ts 374002034554, free_ts 372426167465 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614 __alloc_pages_node include/linux/gfp.h:237 [inline] alloc_slab_page+0x4f/0x160 mm/slub.c:1801 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1230 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node+0xa0/0x240 mm/slab_common.c:943 kmalloc_array_node include/linux/slab.h:676 [inline] kcalloc_node include/linux/slab.h:681 [inline] memcg_alloc_slab_cgroups+0x83/0x120 mm/memcontrol.c:2889 account_slab mm/slab.h:635 [inline] allocate_slab mm/slub.c:1962 [inline] new_slab+0xc3/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1230 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc+0x1b7/0x2f0 mm/slub.c:3383 vm_area_dup+0x23/0x1a0 kernel/fork.c:467 dup_mmap kernel/fork.c:646 [inline] dup_mm kernel/fork.c:1541 [inline] copy_mm+0xa7e/0x15c0 kernel/fork.c:1590 copy_process+0x1953/0x4020 kernel/fork.c:2351 kernel_clone+0x225/0x8b0 kernel/fork.c:2757 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare mm/page_alloc.c:1509 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] __kmem_cache_alloc_node+0x140/0x260 mm/slub.c:3398 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] netdevice_queue_work drivers/infiniband/core/roce_gid_mgmt.c:643 [inline] netdevice_event+0x325/0x900 drivers/infiniband/core/roce_gid_mgmt.c:802 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455 call_netdevice_notifiers_extack net/core/dev.c:2039 [inline] call_netdevice_notifiers net/core/dev.c:2053 [inline] unregister_netdevice_many+0xfdc/0x1840 net/core/dev.c:10990 default_device_exit_batch+0x9c3/0xa50 net/core/dev.c:11503 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x77b/0xb80 net/core/net_namespace.c:640 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 Memory state around the buggy address: ffff88807ed61500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807ed61580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88807ed61600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807ed61680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88807ed61700: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================