tmpfs: Bad mount option Z|
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BUG: KASAN: use-after-free in ____bpf_clone_redirect net/core/filter.c:1767 [inline]
BUG: KASAN: use-after-free in bpf_clone_redirect+0x29a/0x2b0 net/core/filter.c:1758
Read of size 8 at addr ffff8801c6559450 by task syz-executor4/20444

CPU: 1 PID: 20444 Comm: syz-executor4 Not tainted 4.14.79+ #2
input: þÿÿÿ as /devices/virtual/input/input44
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x11b lib/dump_stack.c:53
 print_address_description+0x60/0x22b mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report.cold.6+0x11b/0x2dd mm/kasan/report.c:409
 ____bpf_clone_redirect net/core/filter.c:1767 [inline]
 bpf_clone_redirect+0x29a/0x2b0 net/core/filter.c:1758
input: þÿÿÿ as /devices/virtual/input/input45
 ___bpf_prog_run+0x248e/0x5c70 kernel/bpf/core.c:1012

Allocated by task 1784:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc.part.1+0x4f/0xd0 mm/kasan/kasan.c:551
 slab_post_alloc_hook mm/slab.h:442 [inline]
 slab_alloc_node mm/slub.c:2723 [inline]
 slab_alloc mm/slub.c:2731 [inline]
 kmem_cache_alloc+0xe4/0x2b0 mm/slub.c:2736
 __build_skb+0x30/0x2c0 net/core/skbuff.c:281
 __napi_alloc_skb+0x1ca/0x300 net/core/skbuff.c:482
 napi_alloc_skb include/linux/skbuff.h:2655 [inline]
 page_to_skb.isra.18+0xa3/0x690 drivers/net/virtio_net.c:321
 receive_mergeable drivers/net/virtio_net.c:714 [inline]
 receive_buf+0x1721/0x42c0 drivers/net/virtio_net.c:819
 virtnet_receive drivers/net/virtio_net.c:1093 [inline]
 virtnet_poll+0x2af/0x910 drivers/net/virtio_net.c:1174
 napi_poll net/core/dev.c:5591 [inline]
 net_rx_action+0x371/0xce0 net/core/dev.c:5657
 __do_softirq+0x215/0x997 kernel/softirq.c:288

Freed by task 1784:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xac/0x190 mm/kasan/kasan.c:524
 slab_free_hook mm/slub.c:1389 [inline]
 slab_free_freelist_hook mm/slub.c:1410 [inline]
 slab_free mm/slub.c:2966 [inline]
 kmem_cache_free+0x12d/0x350 mm/slub.c:2988
 kfree_skbmem+0x9e/0x100 net/core/skbuff.c:582
 tcp_rcv_established+0xd8d/0x1660 net/ipv4/tcp_input.c:5472
 tcp_v4_do_rcv+0x55f/0x6f0 net/ipv4/tcp_ipv4.c:1466
 sk_backlog_rcv include/net/sock.h:902 [inline]
 __release_sock+0x135/0x350 net/core/sock.c:2261
 release_sock+0x54/0x1b0 net/core/sock.c:2773
 tcp_sendmsg+0x34/0x40 net/ipv4/tcp.c:1447
 inet_sendmsg+0x168/0x540 net/ipv4/af_inet.c:781
 sock_sendmsg_nosec net/socket.c:645 [inline]
 sock_sendmsg+0xb5/0x100 net/socket.c:655
 sock_write_iter+0x209/0x350 net/socket.c:924
 call_write_iter include/linux/fs.h:1782 [inline]
 new_sync_write fs/read_write.c:471 [inline]
 __vfs_write+0x417/0x5c0 fs/read_write.c:484
 vfs_write+0x17f/0x4d0 fs/read_write.c:546
 SYSC_write fs/read_write.c:593 [inline]
 SyS_write+0xc2/0x1a0 fs/read_write.c:585
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

The buggy address belongs to the object at ffff8801c65593c0
 which belongs to the cache skbuff_head_cache of size 224
The buggy address is located 144 bytes inside of
 224-byte region [ffff8801c65593c0, ffff8801c65594a0)
The buggy address belongs to the page:
page:ffffea0007195640 count:1 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000100(slab)
raw: 4000000000000100 0000000000000000 0000000000000000 00000001800c000c
raw: dead000000000100 dead000000000200 ffff8801dab70200 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c6559300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff8801c6559380: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
>ffff8801c6559400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff8801c6559480: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801c6559500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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