================================================================== BUG: KASAN: use-after-free in __nft_trace_packet+0x137/0x150 net/netfilter/nf_tables_core.c:30 Read of size 2 at addr ffff88805500f580 by task ksoftirqd/1/20 CPU: 1 PID: 20 Comm: ksoftirqd/1 Not tainted 5.15.179-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 print_address_description+0x63/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x16b/0x1c0 mm/kasan/report.c:451 __nft_trace_packet+0x137/0x150 net/netfilter/nf_tables_core.c:30 nft_trace_verdict net/netfilter/nf_tables_core.c:110 [inline] nft_do_chain+0x1453/0x16b0 net/netfilter/nf_tables_core.c:256 nft_do_chain_inet+0x3f8/0x680 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_slow+0xae/0x1e0 net/netfilter/core.c:584 nf_hook include/linux/netfilter.h:257 [inline] NF_HOOK+0x26b/0x410 include/linux/netfilter.h:300 NF_HOOK+0x364/0x410 include/linux/netfilter.h:302 __netif_receive_skb_one_core net/core/dev.c:5524 [inline] __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5638 process_backlog+0x363/0x7f0 net/core/dev.c:6515 __napi_poll+0xc7/0x440 net/core/dev.c:7074 napi_poll net/core/dev.c:7141 [inline] net_rx_action+0x617/0xda0 net/core/dev.c:7231 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 run_ksoftirqd+0xc6/0x120 kernel/softirq.c:925 smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 20: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x53/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3220 [inline] kmem_cache_alloc_node+0x121/0x2c0 mm/slub.c:3256 __alloc_skb+0xdd/0x590 net/core/skbuff.c:415 alloc_skb include/linux/skbuff.h:1162 [inline] synproxy_send_client_synack_ipv6+0x1b6/0xc30 net/netfilter/nf_synproxy_core.c:895 nft_synproxy_eval_v6 net/netfilter/nft_synproxy.c:90 [inline] nft_synproxy_do_eval+0x733/0xa60 net/netfilter/nft_synproxy.c:145 expr_call_ops_eval net/netfilter/nf_tables_core.c:198 [inline] nft_do_chain+0x467/0x16b0 net/netfilter/nf_tables_core.c:238 nft_do_chain_inet+0x3f8/0x680 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_slow+0xae/0x1e0 net/netfilter/core.c:584 nf_hook include/linux/netfilter.h:257 [inline] NF_HOOK+0x26b/0x410 include/linux/netfilter.h:300 NF_HOOK+0x364/0x410 include/linux/netfilter.h:302 __netif_receive_skb_one_core net/core/dev.c:5524 [inline] __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5638 process_backlog+0x363/0x7f0 net/core/dev.c:6515 __napi_poll+0xc7/0x440 net/core/dev.c:7074 napi_poll net/core/dev.c:7141 [inline] net_rx_action+0x617/0xda0 net/core/dev.c:7231 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 run_ksoftirqd+0xc6/0x120 kernel/softirq.c:925 smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Freed by task 20: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kmem_cache_free+0x91/0x1f0 mm/slub.c:3515 nft_synproxy_eval_v6 net/netfilter/nft_synproxy.c:-1 [inline] nft_synproxy_do_eval+0x740/0xa60 net/netfilter/nft_synproxy.c:145 expr_call_ops_eval net/netfilter/nf_tables_core.c:198 [inline] nft_do_chain+0x467/0x16b0 net/netfilter/nf_tables_core.c:238 nft_do_chain_inet+0x3f8/0x680 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_slow+0xae/0x1e0 net/netfilter/core.c:584 nf_hook include/linux/netfilter.h:257 [inline] NF_HOOK+0x26b/0x410 include/linux/netfilter.h:300 NF_HOOK+0x364/0x410 include/linux/netfilter.h:302 __netif_receive_skb_one_core net/core/dev.c:5524 [inline] __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5638 process_backlog+0x363/0x7f0 net/core/dev.c:6515 __napi_poll+0xc7/0x440 net/core/dev.c:7074 napi_poll net/core/dev.c:7141 [inline] net_rx_action+0x617/0xda0 net/core/dev.c:7231 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 run_ksoftirqd+0xc6/0x120 kernel/softirq.c:925 smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 The buggy address belongs to the object at ffff88805500f500 which belongs to the cache skbuff_head_cache of size 232 The buggy address is located 128 bytes inside of 232-byte region [ffff88805500f500, ffff88805500f5e8) The buggy address belongs to the page: page:ffffea00015403c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5500f flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 0000000100000001 ffff88801c1e7140 raw: 0000000000000000 00000000000c000c 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 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 4434, ts 809761222279, free_ts 809737819094 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x3b78/0x3d40 mm/page_alloc.c:4192 __alloc_pages+0x272/0x700 mm/page_alloc.c:5466 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xbb/0x4b0 mm/slub.c:1975 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] kmem_cache_alloc_node+0x1ba/0x2c0 mm/slub.c:3256 __alloc_skb+0xdd/0x590 net/core/skbuff.c:415 alloc_skb include/linux/skbuff.h:1162 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:664 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:721 [inline] nsim_dev_trap_report_work+0x25e/0xab0 drivers/net/netdevsim/dev.c:762 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396 free_slab mm/slub.c:2015 [inline] discard_slab mm/slub.c:2021 [inline] __unfreeze_partials+0x1b7/0x210 mm/slub.c:2507 put_cpu_partial+0x132/0x1a0 mm/slub.c:2587 do_slab_free mm/slub.c:3487 [inline] ___cache_free+0xe3/0x100 mm/slub.c:3506 qlist_free_all+0x36/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x162/0x180 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x53/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3220 [inline] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233 getname_flags+0xb8/0x4e0 fs/namei.c:138 user_path_at_empty+0x2a/0x180 fs/namei.c:2882 do_readlinkat+0x114/0x3a0 fs/stat.c:442 __do_sys_readlink fs/stat.c:475 [inline] __se_sys_readlink fs/stat.c:472 [inline] __x64_sys_readlink+0x7b/0x90 fs/stat.c:472 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Memory state around the buggy address: ffff88805500f480: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc ffff88805500f500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805500f580: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ^ ffff88805500f600: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ffff88805500f680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================