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BUG: KASAN: use-after-free in __tcp_hdrlen include/linux/tcp.h:31 [inline]
BUG: KASAN: use-after-free in qdisc_pkt_len_segs_init+0x7f8/0xa30 net/core/dev.c:4138
Read of size 2 at addr ffff88814ffe5a74 by task syz.1.7062/546

CPU: 1 UID: 0 PID: 546 Comm: syz.1.7062 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
 <IRQ>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xba/0x230 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 __tcp_hdrlen include/linux/tcp.h:31 [inline]
 qdisc_pkt_len_segs_init+0x7f8/0xa30 net/core/dev.c:4138
 __dev_queue_xmit+0x29a/0x3920 net/core/dev.c:4780
 dev_queue_xmit include/linux/netdevice.h:3394 [inline]
 br_dev_queue_push_xmit+0x370/0x4b0 net/bridge/br_forward.c:53
 NF_HOOK+0x360/0x3f0 include/linux/netfilter.h:318
 br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66
 NF_HOOK+0x360/0x3f0 include/linux/netfilter.h:318
 __br_forward+0x397/0x540 net/bridge/br_forward.c:115
 deliver_clone net/bridge/br_forward.c:131 [inline]
 maybe_deliver net/bridge/br_forward.c:191 [inline]
 br_flood+0x6ee/0xb80 net/bridge/br_forward.c:238
 br_handle_frame_finish+0x1521/0x1c80 net/bridge/br_input.c:229
 nf_hook_bridge_pre net/bridge/br_input.c:313 [inline]
 br_handle_frame+0x80f/0x1510 net/bridge/br_input.c:442
 __netif_receive_skb_core+0x98f/0x31a0 net/core/dev.c:6093
 __netif_receive_skb_list_core+0x24d/0x810 net/core/dev.c:6281
 __netif_receive_skb_list net/core/dev.c:6348 [inline]
 netif_receive_skb_list_internal+0x995/0xcf0 net/core/dev.c:6439
 gro_normal_list include/net/gro.h:523 [inline]
 gro_flush_normal include/net/gro.h:531 [inline]
 napi_complete_done+0x299/0x730 net/core/dev.c:6807
 gro_cell_poll+0x5a9/0x5d0 net/core/gro_cells.c:74
 __napi_poll+0xae/0x340 net/core/dev.c:7734
 napi_poll net/core/dev.c:7797 [inline]
 net_rx_action+0x627/0xf70 net/core/dev.c:7954
 handle_softirqs+0x22a/0x870 kernel/softirq.c:622
 do_softirq+0x76/0xd0 kernel/softirq.c:523
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 tun_rx_batched+0x617/0x790 drivers/net/tun.c:-1
 tun_get_user+0x2aeb/0x3ed0 drivers/net/tun.c:1953
 tun_chr_write_iter+0x113/0x200 drivers/net/tun.c:1999
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x61d/0xb90 fs/read_write.c:688
 ksys_write+0x150/0x270 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f08d399c819
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:00007f08d48de028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f08d3c15fa0 RCX: 00007f08d399c819
RDX: 000000000000fdef RSI: 00002000000002c0 RDI: 0000000000000008
RBP: 00007f08d3a32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f08d3c16038 R14: 00007f08d3c15fa0 R15: 00007ffdaaad39e8
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14ffe5
flags: 0x57ff00000000000(node=1|zone=2|lastcpupid=0x7ff)
raw: 057ff00000000000 dead000000000100 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x4069c2(GFP_NOWAIT|__GFP_HIGHMEM|__GFP_IO|__GFP_FS|__GFP_ZERO|__GFP_RETRY_MAYFAIL|__GFP_ACCOUNT), pid 29339, tgid 29338 (syz.3.6151), ts 744893675883, free_ts 746847051097
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889
 prep_new_page mm/page_alloc.c:1897 [inline]
 get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3962
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2490
 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline]
 alloc_pages_noprof+0xa8/0x1a0 mm/mempolicy.c:2581
 vm_area_alloc_pages mm/vmalloc.c:3662 [inline]
 __vmalloc_area_node mm/vmalloc.c:3876 [inline]
 __vmalloc_node_range_noprof+0x79b/0x1730 mm/vmalloc.c:4064
 __bpf_map_area_alloc kernel/bpf/syscall.c:404 [inline]
 bpf_map_area_alloc+0x12d/0x170 kernel/bpf/syscall.c:411
 bloom_map_alloc+0x22f/0x470 kernel/bpf/bloom_filter.c:146
 map_create+0xafd/0x16a0 kernel/bpf/syscall.c:1507
 __sys_bpf+0x6e1/0x950 kernel/bpf/syscall.c:6210
 __do_sys_bpf kernel/bpf/syscall.c:6341 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6339 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6339
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 22330 tgid 22330 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1433 [inline]
 __free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978
 vfree+0x25a/0x400 mm/vmalloc.c:3479
 cleanup_vm_area_work+0xa2/0x100 mm/vmalloc.c:3776
 process_one_work kernel/workqueue.c:3276 [inline]
 process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88814ffe5900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88814ffe5980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88814ffe5a00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                             ^
 ffff88814ffe5a80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88814ffe5b00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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