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BUG: KASAN: use-after-free in ____bpf_clone_redirect net/core/filter.c:1768 [inline]
BUG: KASAN: use-after-free in bpf_clone_redirect+0x2a7/0x2b0 net/core/filter.c:1759
Read of size 8 at addr ffff88818c871a90 by task syz-executor.0/18296

CPU: 1 PID: 18296 Comm: syz-executor.0 Not tainted 4.14.139+ #36
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xca/0x134 lib/dump_stack.c:53
 print_address_description+0x60/0x226 mm/kasan/report.c:187
 __kasan_report.cold+0x1a/0x41 mm/kasan/report.c:316
 ____bpf_clone_redirect net/core/filter.c:1768 [inline]
 bpf_clone_redirect+0x2a7/0x2b0 net/core/filter.c:1759
 ___bpf_prog_run+0x2478/0x5510 kernel/bpf/core.c:1033

Allocated by task 17112:
 save_stack mm/kasan/common.c:76 [inline]
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc.part.0+0x53/0xc0 mm/kasan/common.c:495
 slab_post_alloc_hook mm/slab.h:439 [inline]
 slab_alloc_node mm/slub.c:2758 [inline]
 slab_alloc mm/slub.c:2766 [inline]
 kmem_cache_alloc+0xd2/0x2e0 mm/slub.c:2771
 __build_skb+0x30/0x2f0 net/core/skbuff.c:281
 __napi_alloc_skb+0x1e1/0x320 net/core/skbuff.c:486
 napi_alloc_skb include/linux/skbuff.h:2674 [inline]
 page_to_skb+0xaf/0x6e0 drivers/net/virtio_net.c:323
 receive_mergeable drivers/net/virtio_net.c:719 [inline]
 receive_buf+0x17a5/0x4310 drivers/net/virtio_net.c:824
 virtnet_receive drivers/net/virtio_net.c:1098 [inline]
 virtnet_poll+0x4e6/0x9f0 drivers/net/virtio_net.c:1189
 napi_poll net/core/dev.c:5598 [inline]
 net_rx_action+0x366/0xcd0 net/core/dev.c:5664
 __do_softirq+0x234/0x9ec kernel/softirq.c:288

Freed by task 17112:
 save_stack mm/kasan/common.c:76 [inline]
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x164/0x210 mm/kasan/common.c:457
 slab_free_hook mm/slub.c:1403 [inline]
 slab_free_freelist_hook mm/slub.c:1430 [inline]
 slab_free mm/slub.c:3005 [inline]
 kmem_cache_free+0xcb/0x340 mm/slub.c:3021
 kfree_skb_partial net/core/skbuff.c:4778 [inline]
 kfree_skb_partial+0x2c/0x50 net/core/skbuff.c:4774
 tcp_rcv_established+0x12d8/0x1610 net/ipv4/tcp_input.c:5535
 tcp_v4_do_rcv+0x568/0x700 net/ipv4/tcp_ipv4.c:1467
 tcp_v4_rcv+0x23e9/0x3230 net/ipv4/tcp_ipv4.c:1741
 ip_local_deliver_finish+0x3a3/0xa30 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:250 [inline]
 ip_local_deliver+0x373/0x450 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:468 [inline]
 ip_rcv_finish+0x4ed/0x1610 net/ipv4/ip_input.c:396
 NF_HOOK include/linux/netfilter.h:250 [inline]
 ip_rcv+0xa30/0xf55 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x13ad/0x2cf0 net/core/dev.c:4477
 __netif_receive_skb+0x66/0x210 net/core/dev.c:4515
 netif_receive_skb_internal+0x11f/0x5f0 net/core/dev.c:4588
 napi_skb_finish net/core/dev.c:4949 [inline]
 napi_gro_receive+0x206/0x410 net/core/dev.c:4980
 receive_buf+0x503/0x4310 drivers/net/virtio_net.c:852
 virtnet_receive drivers/net/virtio_net.c:1098 [inline]
 virtnet_poll+0x4e6/0x9f0 drivers/net/virtio_net.c:1189
 napi_poll net/core/dev.c:5598 [inline]
 net_rx_action+0x366/0xcd0 net/core/dev.c:5664
 __do_softirq+0x234/0x9ec kernel/softirq.c:288

The buggy address belongs to the object at ffff88818c871a00
 which belongs to the cache skbuff_head_cache of size 224
The buggy address is located 144 bytes inside of
 224-byte region [ffff88818c871a00, ffff88818c871ae0)
The buggy address belongs to the page:
page:ffffea0006321c40 count:1 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000200(slab)
raw: 4000000000000200 0000000000000000 0000000000000000 00000001800c000c
raw: 0000000000000000 0000000900000001 ffff8881dab70200 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88818c871980: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88818c871a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88818c871a80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                         ^
 ffff88818c871b00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff88818c871b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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