================================================================== BUG: KASAN: slab-use-after-free in flow_block_cb_is_busy net/core/flow_offload.c:328 [inline] BUG: KASAN: slab-use-after-free in flow_block_cb_setup_simple+0x1cc/0x740 net/core/flow_offload.c:353 Read of size 8 at addr ffff888028d4d220 by task syz.1.52/6177 CPU: 0 UID: 0 PID: 6177 Comm: syz.1.52 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 flow_block_cb_is_busy net/core/flow_offload.c:328 [inline] flow_block_cb_setup_simple+0x1cc/0x740 net/core/flow_offload.c:353 nft_block_offload_cmd net/netfilter/nf_tables_offload.c:397 [inline] nft_chain_offload_cmd+0x290/0x660 net/netfilter/nf_tables_offload.c:451 nft_flow_block_chain net/netfilter/nf_tables_offload.c:471 [inline] nft_flow_offload_chain net/netfilter/nf_tables_offload.c:513 [inline] nft_flow_rule_offload_commit+0x814/0x1b60 net/netfilter/nf_tables_offload.c:584 nf_tables_commit+0x675/0x8700 net/netfilter/nf_tables_api.c:10933 nfnetlink_rcv_batch net/netfilter/nfnetlink.c:574 [inline] nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:647 [inline] nfnetlink_rcv+0x1a4e/0x2520 net/netfilter/nfnetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4f5978eec9 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:00007ffceff1bd48 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f4f599e5fa0 RCX: 00007f4f5978eec9 RDX: 0000000000000000 RSI: 000020000000c2c0 RDI: 0000000000000003 RBP: 00007f4f59811f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4f599e5fa0 R14: 00007f4f599e5fa0 R15: 0000000000000003 Allocated by task 6176: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:388 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4407 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] flow_block_cb_alloc net/core/flow_offload.c:267 [inline] flow_block_cb_setup_simple+0x2a1/0x740 net/core/flow_offload.c:356 nft_block_offload_cmd net/netfilter/nf_tables_offload.c:397 [inline] nft_chain_offload_cmd+0x290/0x660 net/netfilter/nf_tables_offload.c:451 nft_flow_block_chain net/netfilter/nf_tables_offload.c:471 [inline] nft_flow_offload_chain net/netfilter/nf_tables_offload.c:513 [inline] nft_flow_rule_offload_commit+0x814/0x1b60 net/netfilter/nf_tables_offload.c:584 nf_tables_commit+0x675/0x8700 net/netfilter/nf_tables_api.c:10933 nfnetlink_rcv_batch net/netfilter/nfnetlink.c:574 [inline] nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:647 [inline] nfnetlink_rcv+0x1a4e/0x2520 net/netfilter/nfnetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 6176: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2422 [inline] slab_free mm/slub.c:4695 [inline] kfree+0x18e/0x440 mm/slub.c:4894 nft_flow_offload_unbind+0x3c0/0x440 net/netfilter/nf_tables_offload.c:344 nft_chain_offload_cmd+0x43f/0x660 net/netfilter/nf_tables_offload.c:-1 nft_flow_block_chain net/netfilter/nf_tables_offload.c:471 [inline] nft_flow_offload_chain net/netfilter/nf_tables_offload.c:513 [inline] nft_flow_rule_offload_commit+0x40d/0x1b60 net/netfilter/nf_tables_offload.c:592 nf_tables_commit+0x675/0x8700 net/netfilter/nf_tables_api.c:10933 nfnetlink_rcv_batch net/netfilter/nfnetlink.c:574 [inline] nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:647 [inline] nfnetlink_rcv+0x1a4e/0x2520 net/netfilter/nfnetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888028d4d200 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 32 bytes inside of freed 192-byte region [ffff888028d4d200, ffff888028d4d2c0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28d4d ksm flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801a4413c0 ffffea0000a02100 dead000000000003 raw: 0000000000000000 0000000080100010 00000000f5000000 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 0x52c00(GFP_NOIO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 10, tgid 10 (kworker/0:1), ts 10525090471, free_ts 10120770569 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2492 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2660 new_slab mm/slub.c:2714 [inline] ___slab_alloc+0xbeb/0x1420 mm/slub.c:3901 __slab_alloc mm/slub.c:3992 [inline] __slab_alloc_node mm/slub.c:4067 [inline] slab_alloc_node mm/slub.c:4228 [inline] __do_kmalloc_node mm/slub.c:4375 [inline] __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4388 kmalloc_noprof include/linux/slab.h:909 [inline] usb_alloc_urb+0x46/0x150 drivers/usb/core/urb.c:75 usb_internal_control_msg drivers/usb/core/message.c:96 [inline] usb_control_msg+0x118/0x3e0 drivers/usb/core/message.c:154 get_port_status drivers/usb/core/hub.c:611 [inline] hub_ext_port_status+0x116/0x820 drivers/usb/core/hub.c:628 usb_hub_port_status drivers/usb/core/hub.c:678 [inline] hub_activate+0x77d/0x1a70 drivers/usb/core/hub.c:1189 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 page last free pid 10 tgid 10 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895 vfree+0x25a/0x400 mm/vmalloc.c:3434 delayed_vfree_work+0x55/0x80 mm/vmalloc.c:3353 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888028d4d100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888028d4d180: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc >ffff888028d4d200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888028d4d280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888028d4d300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================