==================================================================
BUG: KASAN: use-after-free in tcp_skb_pcount include/net/tcp.h:798 [inline]
BUG: KASAN: use-after-free in tcp_init_tso_segs net/ipv4/tcp_output.c:1631 [inline]
BUG: KASAN: use-after-free in tcp_write_xmit+0x3b22/0x4680 net/ipv4/tcp_output.c:2068
Read of size 2 at addr ffff8801d738a2b0 by task syz-executor5/4668

CPU: 0 PID: 4668 Comm: syz-executor5 Not tainted 4.4.169+ #7
 0000000000000000 87c69b8a8d1f0cef ffff8801c19cf828 ffffffff81aa635d
 ffffea00075ce280 ffff8801d738a2b0 0000000000000000 ffff8801d738a2b0
 dffffc0000000000 ffff8801c19cf860 ffffffff8148b15b ffff8801d738a2b0
Call Trace:
 [<ffffffff81aa635d>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81aa635d>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff8148b15b>] print_address_description+0x6c/0x217 mm/kasan/report.c:252
 [<ffffffff8148b47b>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff8148b47b>] kasan_report.cold.6+0x175/0x2f7 mm/kasan/report.c:408
 [<ffffffff81480164>] __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:427
 [<ffffffff82432b52>] tcp_skb_pcount include/net/tcp.h:798 [inline]
 [<ffffffff82432b52>] tcp_init_tso_segs net/ipv4/tcp_output.c:1631 [inline]
 [<ffffffff82432b52>] tcp_write_xmit+0x3b22/0x4680 net/ipv4/tcp_output.c:2068
 [<ffffffff82433f44>] __tcp_push_pending_frames+0xa4/0x2a0 net/ipv4/tcp_output.c:2323
 [<ffffffff8243afb6>] tcp_send_fin+0x176/0xab0 net/ipv4/tcp_output.c:2899
 [<ffffffff823fab67>] tcp_close+0xc97/0xf60 net/ipv4/tcp.c:2112
 [<ffffffff824a301f>] inet_release+0xff/0x1d0 net/ipv4/af_inet.c:435
 [<ffffffff821cd309>] __sock_release+0xd9/0x260 net/socket.c:592
 [<ffffffff821cd4a9>] sock_close+0x19/0x20 net/socket.c:1050
 [<ffffffff814976b5>] __fput+0x235/0x6f0 fs/file_table.c:208
 [<ffffffff81497bf5>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8112f92c>] task_work_run+0x21c/0x2d0 kernel/task_work.c:115
 [<ffffffff81102082>] get_signal+0x1182/0x14a0 kernel/signal.c:2151
 [<ffffffff8100bdc5>] do_signal+0x95/0x1840 arch/x86/kernel/signal.c:712
 [<ffffffff81003eba>] exit_to_usermode_loop+0x11a/0x160 arch/x86/entry/common.c:184
 [<ffffffff81006575>] prepare_exit_to_usermode arch/x86/entry/common.c:221 [inline]
 [<ffffffff81006575>] syscall_return_slowpath arch/x86/entry/common.c:286 [inline]
 [<ffffffff81006575>] do_syscall_32_irqs_on arch/x86/entry/common.c:336 [inline]
 [<ffffffff81006575>] do_fast_syscall_32+0x795/0xa80 arch/x86/entry/common.c:397
 [<ffffffff82717a90>] sysenter_flags_fixed+0xd/0x1a

Allocated by task 4653:
 [<ffffffff8102e3e6>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff8147f1e2>] save_stack mm/kasan/kasan.c:512 [inline]
 [<ffffffff8147f1e2>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff8147f1e2>] kasan_kmalloc.part.1+0x62/0xf0 mm/kasan/kasan.c:616
 [<ffffffff8147f45f>] kasan_kmalloc+0xaf/0xc0 mm/kasan/kasan.c:601
 [<ffffffff8147fa22>] kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:554
 [<ffffffff8147b11c>] slab_post_alloc_hook mm/slub.c:1349 [inline]
 [<ffffffff8147b11c>] slab_alloc_node mm/slub.c:2615 [inline]
 [<ffffffff8147b11c>] slab_alloc mm/slub.c:2623 [inline]
 [<ffffffff8147b11c>] kmem_cache_alloc+0xdc/0x2c0 mm/slub.c:2628
 [<ffffffff821f1466>] kmem_cache_alloc_node include/linux/slab.h:350 [inline]
 [<ffffffff821f1466>] __alloc_skb+0xe6/0x5b0 net/core/skbuff.c:218
 [<ffffffff823f5193>] alloc_skb_fclone include/linux/skbuff.h:856 [inline]
 [<ffffffff823f5193>] sk_stream_alloc_skb+0xa3/0x5d0 net/ipv4/tcp.c:833
 [<ffffffff823f7e21>] tcp_sendmsg+0xf81/0x2b30 net/ipv4/tcp.c:1178
 [<ffffffff824a50a3>] inet_sendmsg+0x203/0x4d0 net/ipv4/af_inet.c:755
 [<ffffffff821d1f1b>] sock_sendmsg_nosec net/socket.c:638 [inline]
 [<ffffffff821d1f1b>] sock_sendmsg+0xbb/0x110 net/socket.c:648
 [<ffffffff821d6120>] SYSC_sendto net/socket.c:1678 [inline]
 [<ffffffff821d6120>] SyS_sendto+0x220/0x370 net/socket.c:1646
 [<ffffffff81006101>] do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline]
 [<ffffffff81006101>] do_fast_syscall_32+0x321/0xa80 arch/x86/entry/common.c:397
 [<ffffffff82717a90>] sysenter_flags_fixed+0xd/0x1a

Freed by task 4668:
 [<ffffffff8102e3e6>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff8147fadc>] save_stack mm/kasan/kasan.c:512 [inline]
 [<ffffffff8147fadc>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff8147fadc>] kasan_slab_free+0xac/0x190 mm/kasan/kasan.c:589
 [<ffffffff8147c7de>] slab_free_hook mm/slub.c:1383 [inline]
 [<ffffffff8147c7de>] slab_free_freelist_hook mm/slub.c:1405 [inline]
 [<ffffffff8147c7de>] slab_free mm/slub.c:2859 [inline]
 [<ffffffff8147c7de>] kmem_cache_free+0xbe/0x350 mm/slub.c:2881
 [<ffffffff821e992f>] kfree_skbmem+0xcf/0x100 net/core/skbuff.c:635
 [<ffffffff821f6ccd>] __kfree_skb+0x1d/0x20 net/core/skbuff.c:676
 [<ffffffff82434d09>] sk_wmem_free_skb include/net/sock.h:1447 [inline]
 [<ffffffff82434d09>] tcp_write_queue_purge include/net/tcp.h:1460 [inline]
 [<ffffffff82434d09>] tcp_connect_init net/ipv4/tcp_output.c:3138 [inline]
 [<ffffffff82434d09>] tcp_connect+0xae9/0x3110 net/ipv4/tcp_output.c:3277
 [<ffffffff82442ce1>] tcp_v4_connect+0xf31/0x1890 net/ipv4/tcp_ipv4.c:246
 [<ffffffff824a3fb9>] __inet_stream_connect+0x2a9/0xc30 net/ipv4/af_inet.c:615
 [<ffffffff823f88a7>] tcp_sendmsg_fastopen net/ipv4/tcp.c:1092 [inline]
 [<ffffffff823f88a7>] tcp_sendmsg+0x1a07/0x2b30 net/ipv4/tcp.c:1112
 [<ffffffff824a50a3>] inet_sendmsg+0x203/0x4d0 net/ipv4/af_inet.c:755
 [<ffffffff821d1f1b>] sock_sendmsg_nosec net/socket.c:638 [inline]
 [<ffffffff821d1f1b>] sock_sendmsg+0xbb/0x110 net/socket.c:648
 [<ffffffff821d6120>] SYSC_sendto net/socket.c:1678 [inline]
 [<ffffffff821d6120>] SyS_sendto+0x220/0x370 net/socket.c:1646
 [<ffffffff81006101>] do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline]
 [<ffffffff81006101>] do_fast_syscall_32+0x321/0xa80 arch/x86/entry/common.c:397
 [<ffffffff82717a90>] sysenter_flags_fixed+0xd/0x1a

The buggy address belongs to the object at ffff8801d738a280
 which belongs to the cache skbuff_fclone_cache of size 456
The buggy address is located 48 bytes inside of
 456-byte region [ffff8801d738a280, ffff8801d738a448)
The buggy address belongs to the page:
BUG: unable to handle kernel paging request at ffffff4085894804
IP: [<ffffffff8195a9ed>] task_has_perm+0x10d/0x330 security/selinux/hooks.c:1522
PGD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 2132 Comm: syz-executor0 Not tainted 4.4.169+ #7
task: ffff8800b7ef17c0 task.stack: ffff8800a84c0000
RIP: 0010:[<ffffffff8195a9ed>]  [<ffffffff8195a9ed>] task_has_perm+0x10d/0x330 security/selinux/hooks.c:1522
RSP: 0018:ffff8800a84c79a8  EFLAGS: 00010246
RAX: 0000000000000007 RBX: 0000000000000004 RCX: ffffed0016fde410
RDX: 0000000000000000 RSI: ffffffff8195a992 RDI: ffff8800b7ef1ed0
RBP: ffff8800a84c79c8 R08: ffff8800b7ef2088 R09: 1ffff10016fde415
R10: ffffffff82835d40 R11: ffffffff831a49f8 R12: ffffff4085894800
R13: ffff8800b7ef17c0 R14: ffff8800a84c7c8c R15: ffff8800a84c7c88
FS:  0000000000000000(0000) GS:ffff8801db700000(0063) knlGS:0000000009d44900
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: ffffff4085894804 CR3: 00000000a8fee000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff8195a8e0 ffff8801c18a4740 dffffc0000000000 ffff8801c18a4740
 ffff8800a84c79e0 ffffffff8195ac33 ffffffff82f92ce0 ffff8800a84c7a10
 ffffffff819489f3 ffff8800b7ef2088 0000000040000005 0000000000000000
Call Trace:
 [<ffffffff8195ac33>] selinux_task_wait+0x23/0x30 security/selinux/hooks.c:3763
 [<ffffffff819489f3>] security_task_wait+0x73/0xb0 security/security.c:986
 [<ffffffff810dbba8>] wait_consider_task+0x298/0x35e0 kernel/exit.c:1326
 [<ffffffff810df256>] do_wait_thread kernel/exit.c:1439 [inline]
 [<ffffffff810df256>] do_wait+0x366/0xa30 kernel/exit.c:1510
 [<ffffffff810e019b>] SYSC_wait4 kernel/exit.c:1641 [inline]
 [<ffffffff810e019b>] SyS_wait4+0x12b/0x1f0 kernel/exit.c:1606
 [<ffffffff812b1bea>] C_SYSC_wait4 kernel/compat.c:543 [inline]
 [<ffffffff812b1bea>] compat_SyS_wait4+0x25a/0x2a0 kernel/compat.c:536
 [<ffffffff810bf3b5>] sys32_waitpid+0x25/0x30 arch/x86/ia32/sys_ia32.c:172
 [<ffffffff81006101>] do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline]
 [<ffffffff81006101>] do_fast_syscall_32+0x321/0xa80 arch/x86/entry/common.c:397
 [<ffffffff82717a90>] sysenter_flags_fixed+0xd/0x1a
Code: 8d 7c 24 04 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 f0 01 00 00 49 8d bd 10 07 00 00 <45> 8b 64 24 04 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 
RIP  [<ffffffff8195a9ed>] __read_once_size include/linux/compiler.h:218 [inline]
RIP  [<ffffffff8195a9ed>] task_has_perm+0x10d/0x330 security/selinux/hooks.c:1523
 RSP <ffff8800a84c79a8>
CR2: ffffff4085894804
---[ end trace 399c04567093b2e6 ]---