==================================================================
BUG: KASAN: slab-use-after-free in __xsk_map_flush+0x2f9/0x310 net/xdp/xsk.c:392
Read of size 8 at addr ffff888020377710 by task syz.2.1106/11145

CPU: 1 UID: 0 PID: 11145 Comm: syz.2.1106 Not tainted 6.10.0-syzkaller-11840-g933069701c1b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 __xsk_map_flush+0x2f9/0x310 net/xdp/xsk.c:392
 xdp_do_check_flushed+0x175/0x4e0 net/core/filter.c:4308
 __napi_poll.constprop.0+0xd1/0x550 net/core/dev.c:6774
 napi_poll net/core/dev.c:6840 [inline]
 net_rx_action+0xa92/0x1010 net/core/dev.c:6962
 handle_softirqs+0x216/0x8f0 kernel/softirq.c:554
 do_softirq kernel/softirq.c:455 [inline]
 do_softirq+0xb2/0xf0 kernel/softirq.c:442
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:382
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 tun_rx_batched+0x43a/0x780 drivers/net/tun.c:1574
 tun_get_user+0x2a5c/0x3c30 drivers/net/tun.c:2006
 tun_chr_write_iter+0xe8/0x210 drivers/net/tun.c:2052
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6b6/0x1140 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4084174a9f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 29 8c 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 7c 8c 02 00 48
RSP: 002b:00007f4084fd6010 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f4084306038 RCX: 00007f4084174a9f
RDX: 000000000000004a RSI: 0000000020000200 RDI: 00000000000000c8
RBP: 00007f40841e4e68 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000004a R11: 0000000000000293 R12: 0000000000000000
R13: 000000000000006e R14: 00007f4084306038 R15: 00007ffd86334ac8
 </TASK>

Allocated by task 11145:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:312 [inline]
 __kasan_mempool_unpoison_object+0x193/0x1d0 mm/kasan/common.c:535
 kasan_mempool_unpoison_object include/linux/kasan.h:339 [inline]
 napi_skb_cache_get+0x327/0x890 net/core/skbuff.c:363
 __napi_build_skb+0x14/0x50 net/core/skbuff.c:533
 napi_build_skb+0x22/0x280 net/core/skbuff.c:555
 skb_pp_cow_data+0x2de/0xc00 net/core/skbuff.c:950
 skb_cow_data_for_xdp+0x88/0xb0 net/core/skbuff.c:1013
 netif_skb_check_for_xdp net/core/dev.c:5030 [inline]
 netif_receive_generic_xdp net/core/dev.c:5069 [inline]
 do_xdp_generic+0x3fc/0xd70 net/core/dev.c:5137
 __netif_receive_skb_core.constprop.0+0x12f7/0x4330 net/core/dev.c:5480
 __netif_receive_skb_one_core+0xb1/0x1e0 net/core/dev.c:5658
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5774
 netif_receive_skb_internal net/core/dev.c:5860 [inline]
 netif_receive_skb+0x13f/0x7b0 net/core/dev.c:5920
 tun_rx_batched+0x429/0x780 drivers/net/tun.c:1573
 tun_get_user+0x2a5c/0x3c30 drivers/net/tun.c:2006
 tun_chr_write_iter+0xe8/0x210 drivers/net/tun.c:2052
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6b6/0x1140 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 11145:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
 poison_slab_object+0xf7/0x160 mm/kasan/common.c:240
 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2252 [inline]
 slab_free mm/slub.c:4473 [inline]
 kmem_cache_free+0x12f/0x3a0 mm/slub.c:4548
 kfree_skbmem+0x10e/0x200 net/core/skbuff.c:1146
 __kfree_skb net/core/skbuff.c:1203 [inline]
 sk_skb_reason_drop+0x140/0x210 net/core/skbuff.c:1240
 tcp_v6_rcv+0xea8/0x4120 net/ipv6/tcp_ipv6.c:1943
 ip6_protocol_deliver_rcu+0x188/0x1530 net/ipv6/ip6_input.c:438
 ip6_input_finish+0x14f/0x2f0 net/ipv6/ip6_input.c:483
 NF_HOOK include/linux/netfilter.h:314 [inline]
 NF_HOOK include/linux/netfilter.h:308 [inline]
 ip6_input+0xa1/0xd0 net/ipv6/ip6_input.c:492
 dst_input include/net/dst.h:460 [inline]
 ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline]
 NF_HOOK include/linux/netfilter.h:314 [inline]
 NF_HOOK include/linux/netfilter.h:308 [inline]
 ipv6_rcv+0x265/0x680 net/ipv6/ip6_input.c:310
 __netif_receive_skb_one_core+0x12e/0x1e0 net/core/dev.c:5660
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5774
 netif_receive_skb_internal net/core/dev.c:5860 [inline]
 netif_receive_skb+0x13f/0x7b0 net/core/dev.c:5920
 tun_rx_batched+0x429/0x780 drivers/net/tun.c:1573
 tun_get_user+0x2a5c/0x3c30 drivers/net/tun.c:2006
 tun_chr_write_iter+0xe8/0x210 drivers/net/tun.c:2052
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6b6/0x1140 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888020377640
 which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 208 bytes inside of
 freed 240-byte region [ffff888020377640, ffff888020377730)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20377
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xfdffffff(slab)
raw: 00fff00000000000 ffff888019aa8780 ffffea0001efacc0 dead000000000004
raw: 0000000000000000 00000000000c000c 00000001fdffffff 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 0x152cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 7330, tgid 7330 (syz-executor), ts 296741864555, free_ts 296738537527
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1493
 prep_new_page mm/page_alloc.c:1501 [inline]
 get_page_from_freelist+0x1351/0x2e50 mm/page_alloc.c:3438
 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4696
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x4e/0xf0 mm/slub.c:2321
 allocate_slab mm/slub.c:2484 [inline]
 new_slab+0x84/0x260 mm/slub.c:2537
 ___slab_alloc+0xdac/0x1870 mm/slub.c:3723
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3813
 __slab_alloc_node mm/slub.c:3866 [inline]
 slab_alloc_node mm/slub.c:4025 [inline]
 kmem_cache_alloc_node_noprof+0xed/0x310 mm/slub.c:4080
 __alloc_skb+0x2b1/0x380 net/core/skbuff.c:664
 alloc_skb include/linux/skbuff.h:1320 [inline]
 nlmsg_new include/net/netlink.h:1015 [inline]
 netlink_ack+0x164/0xb90 net/netlink/af_netlink.c:2487
 netlink_rcv_skb+0x348/0x440 net/netlink/af_netlink.c:2556
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
 netlink_unicast+0x544/0x830 net/netlink/af_netlink.c:1357
 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x47f/0x4e0 net/socket.c:2204
 __do_sys_sendto net/socket.c:2216 [inline]
 __se_sys_sendto net/socket.c:2212 [inline]
 __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2212
page last free pid 6653 tgid 6653 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1094 [inline]
 free_unref_page+0x64a/0xe40 mm/page_alloc.c:2608
 vfree+0x181/0x7a0 mm/vmalloc.c:3364
 copy_entries_to_user net/ipv4/netfilter/arp_tables.c:713 [inline]
 get_entries net/ipv4/netfilter/arp_tables.c:867 [inline]
 do_arpt_get_ctl+0x846/0x9a0 net/ipv4/netfilter/arp_tables.c:1461
 nf_getsockopt+0x79/0xe0 net/netfilter/nf_sockopt.c:116
 ip_getsockopt+0x18e/0x1e0 net/ipv4/ip_sockglue.c:1777
 tcp_getsockopt+0x9e/0x100 net/ipv4/tcp.c:4409
 do_sock_getsockopt+0x2e5/0x760 net/socket.c:2386
 __sys_getsockopt+0x1a1/0x270 net/socket.c:2415
 __do_sys_getsockopt net/socket.c:2425 [inline]
 __se_sys_getsockopt net/socket.c:2422 [inline]
 __x64_sys_getsockopt+0xbd/0x160 net/socket.c:2422
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888020377600: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
 ffff888020377680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888020377700: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
                         ^
 ffff888020377780: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888020377800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
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