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BUG: KASAN: use-after-free in skb_clear_hash include/linux/skbuff.h:1062 [inline]
BUG: KASAN: use-after-free in ip_check_defrag net/ipv4/ip_fragment.c:738 [inline]
BUG: KASAN: use-after-free in ip_check_defrag+0x571/0x5b0 net/ipv4/ip_fragment.c:703
Write of size 4 at addr ffff8801b121459c by task syz-executor4/10055

CPU: 0 PID: 10055 Comm: syz-executor4 Not tainted 4.9.154+ #21
 ffff8801db607a68 ffffffff81b47411 0000000000000001 ffffea0006c48500
 ffff8801b121459c 0000000000000004 ffffffff824a4c01 ffff8801db607aa0
 ffffffff81502615 0000000000000001 ffff8801b121459c ffff8801b121459c
Call Trace:
 <IRQ> [ 2397.150343]  [<ffffffff81b47411>] __dump_stack lib/dump_stack.c:15 [inline]
 <IRQ> [ 2397.150343]  [<ffffffff81b47411>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
 [<ffffffff81502615>] print_address_description+0x6f/0x238 mm/kasan/report.c:256
 [<ffffffff8150286a>] kasan_report_error mm/kasan/report.c:355 [inline]
 [<ffffffff8150286a>] kasan_report mm/kasan/report.c:412 [inline]
 [<ffffffff8150286a>] kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:397
 [<ffffffff814f4ae7>] __asan_report_store4_noabort+0x17/0x20 mm/kasan/report.c:437
 [<ffffffff824a4c01>] skb_clear_hash include/linux/skbuff.h:1062 [inline]
 [<ffffffff824a4c01>] ip_check_defrag net/ipv4/ip_fragment.c:738 [inline]
 [<ffffffff824a4c01>] ip_check_defrag+0x571/0x5b0 net/ipv4/ip_fragment.c:703
 [<ffffffff827db11e>] packet_rcv_fanout+0x51e/0x5f0 net/packet/af_packet.c:1458
 [<ffffffff823012f6>] deliver_skb net/core/dev.c:1857 [inline]
 [<ffffffff823012f6>] __netif_receive_skb_core+0xba6/0x2990 net/core/dev.c:4198
 [<ffffffff8230a368>] __netif_receive_skb+0x58/0x1c0 net/core/dev.c:4327
 [<ffffffff82311d48>] process_backlog+0x1e8/0x610 net/core/dev.c:4952
 [<ffffffff8231113a>] napi_poll net/core/dev.c:5253 [inline]
 [<ffffffff8231113a>] net_rx_action+0x3aa/0xdd0 net/core/dev.c:5318
 [<ffffffff8281b87d>] __do_softirq+0x22d/0x964 kernel/softirq.c:288
 [<ffffffff8281735c>] do_softirq_own_stack+0x1c/0x30 arch/x86/entry/entry_64.S:843
 <EOI> [ 2397.308467]  [<ffffffff810ee772>] do_softirq.part.0+0x62/0x70 kernel/softirq.c:332
 [<ffffffff810ee84e>] do_softirq kernel/softirq.c:324 [inline]
 [<ffffffff810ee84e>] __local_bh_enable_ip+0xce/0xe0 kernel/softirq.c:185
 [<ffffffff824abcea>] local_bh_enable include/linux/bottom_half.h:31 [inline]
 [<ffffffff824abcea>] rcu_read_unlock_bh include/linux/rcupdate.h:971 [inline]
 [<ffffffff824abcea>] ip_finish_output2+0x6ea/0x1280 net/ipv4/ip_output.c:227
 [<ffffffff824aea99>] ip_do_fragment+0x1859/0x1f30 net/ipv4/ip_output.c:671
 [<ffffffff824b269b>] ip_fragment.constprop.0+0x14b/0x200 net/ipv4/ip_output.c:544
 [<ffffffff824b2f1b>] ip_finish_output+0x7cb/0xce0 net/ipv4/ip_output.c:311
 [<ffffffff824b6fcc>] NF_HOOK_COND include/linux/netfilter.h:246 [inline]
 [<ffffffff824b6fcc>] ip_output+0x1ec/0x5b0 net/ipv4/ip_output.c:401
 [<ffffffff824b3d3c>] dst_output include/net/dst.h:507 [inline]
 [<ffffffff824b3d3c>] ip_local_out+0x9c/0x180 net/ipv4/ip_output.c:124
 [<ffffffff824b9cde>] ip_send_skb+0x3e/0xc0 net/ipv4/ip_output.c:1489
 [<ffffffff824b9dc4>] ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1509
 [<ffffffff8255e253>] raw_sendmsg+0xbf3/0x23e0 net/ipv4/raw.c:658
 [<ffffffff825955e2>] inet_sendmsg+0x202/0x4d0 net/ipv4/af_inet.c:770
 [<ffffffff822a392e>] sock_sendmsg_nosec net/socket.c:648 [inline]
 [<ffffffff822a392e>] sock_sendmsg+0xbe/0x110 net/socket.c:658
 [<ffffffff822a3d94>] kernel_sendmsg+0x44/0x50 net/socket.c:666
 [<ffffffff822ae466>] sock_no_sendpage+0x116/0x150 net/core/sock.c:2335
 [<ffffffff82596d4c>] inet_sendpage+0x3bc/0x520 net/ipv4/af_inet.c:788
 [<ffffffff822a3605>] kernel_sendpage+0x95/0xf0 net/socket.c:3334
 [<ffffffff822a36eb>] sock_sendpage+0x8b/0xc0 net/socket.c:802
 [<ffffffff815ac06d>] pipe_to_sendpage+0x28d/0x3d0 fs/splice.c:470
 [<ffffffff815afe61>] splice_from_pipe_feed fs/splice.c:521 [inline]
 [<ffffffff815afe61>] __splice_from_pipe+0x351/0x790 fs/splice.c:645
 [<ffffffff815b1868>] splice_from_pipe+0x108/0x170 fs/splice.c:680
 [<ffffffff815b190c>] generic_splice_sendpage+0x3c/0x50 fs/splice.c:851
 [<ffffffff815b2a1d>] do_splice_from fs/splice.c:870 [inline]
 [<ffffffff815b2a1d>] do_splice fs/splice.c:1166 [inline]
 [<ffffffff815b2a1d>] SYSC_splice fs/splice.c:1416 [inline]
 [<ffffffff815b2a1d>] SyS_splice+0xddd/0x1440 fs/splice.c:1399
 [<ffffffff810056bd>] do_syscall_64+0x1ad/0x570 arch/x86/entry/common.c:285
 [<ffffffff82816493>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Allocated by task 10055:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57
 save_stack mm/kasan/kasan.c:505 [inline]
 set_track mm/kasan/kasan.c:517 [inline]
 kasan_kmalloc.part.0+0x62/0xf0 mm/kasan/kasan.c:609
 kasan_kmalloc+0xb7/0xd0 mm/kasan/kasan.c:594
 kasan_slab_alloc+0xf/0x20 mm/kasan/kasan.c:547
 slab_post_alloc_hook mm/slab.h:417 [inline]
 slab_alloc_node mm/slub.c:2715 [inline]
 slab_alloc mm/slub.c:2723 [inline]
 kmem_cache_alloc+0xd5/0x2b0 mm/slub.c:2728
 skb_clone+0x122/0x2a0 net/core/skbuff.c:1034
 skb_share_check include/linux/skbuff.h:1428 [inline]
 ip_check_defrag net/ipv4/ip_fragment.c:725 [inline]
 ip_check_defrag+0x2d9/0x5b0 net/ipv4/ip_fragment.c:703
 packet_rcv_fanout+0x51e/0x5f0 net/packet/af_packet.c:1458
 deliver_skb net/core/dev.c:1857 [inline]
 __netif_receive_skb_core+0xba6/0x2990 net/core/dev.c:4198
 __netif_receive_skb+0x58/0x1c0 net/core/dev.c:4327
 process_backlog+0x1e8/0x610 net/core/dev.c:4952
 napi_poll net/core/dev.c:5253 [inline]
 net_rx_action+0x3aa/0xdd0 net/core/dev.c:5318
 __do_softirq+0x22d/0x964 kernel/softirq.c:288

Freed by task 10055:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57
 save_stack mm/kasan/kasan.c:505 [inline]
 set_track mm/kasan/kasan.c:517 [inline]
 kasan_slab_free+0xb0/0x190 mm/kasan/kasan.c:582
 slab_free_hook mm/slub.c:1355 [inline]
 slab_free_freelist_hook mm/slub.c:1377 [inline]
 slab_free mm/slub.c:2958 [inline]
 kmem_cache_free+0xbe/0x310 mm/slub.c:2980
 kfree_skbmem+0x9f/0x100 net/core/skbuff.c:623
 __kfree_skb net/core/skbuff.c:685 [inline]
 kfree_skb+0xd4/0x350 net/core/skbuff.c:705
 ip_frag_queue net/ipv4/ip_fragment.c:505 [inline]
 ip_defrag+0x620/0x3bc0 net/ipv4/ip_fragment.c:690
 ip_check_defrag net/ipv4/ip_fragment.c:736 [inline]
 ip_check_defrag+0x3d6/0x5b0 net/ipv4/ip_fragment.c:703
 packet_rcv_fanout+0x51e/0x5f0 net/packet/af_packet.c:1458
 deliver_skb net/core/dev.c:1857 [inline]
 __netif_receive_skb_core+0xba6/0x2990 net/core/dev.c:4198
 __netif_receive_skb+0x58/0x1c0 net/core/dev.c:4327
 process_backlog+0x1e8/0x610 net/core/dev.c:4952
 napi_poll net/core/dev.c:5253 [inline]
 net_rx_action+0x3aa/0xdd0 net/core/dev.c:5318
 __do_softirq+0x22d/0x964 kernel/softirq.c:288

The buggy address belongs to the object at ffff8801b1214500
 which belongs to the cache skbuff_head_cache of size 224
The buggy address is located 156 bytes inside of
 224-byte region [ffff8801b1214500, ffff8801b12145e0)
The buggy address belongs to the page:
page:ffffea0006c48500 count:1 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000080(slab)
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b1214480: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801b1214500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801b1214580: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                            ^
 ffff8801b1214600: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
 ffff8801b1214680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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