==================================================================
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 ffff8801d042b1b0 by task syz-executor5/4245

CPU: 1 PID: 4245 Comm: syz-executor5 Not tainted 4.4.164+ #123
 0000000000000000 5a23ec7d05789ff0 ffff8800b270f870 ffffffff81aa5d4d
 ffffea0007410a80 ffff8801d042b1b0 0000000000000000 ffff8801d042b1b0
 dffffc0000000000 ffff8800b270f8a8 ffffffff8148b2eb ffff8801d042b1b0
Call Trace:
 [<ffffffff81aa5d4d>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81aa5d4d>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff8148b2eb>] print_address_description+0x6c/0x217 mm/kasan/report.c:252
 [<ffffffff8148b60b>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff8148b60b>] kasan_report.cold.6+0x175/0x2f7 mm/kasan/report.c:408
 [<ffffffff814802f4>] __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:427
 [<ffffffff82430a32>] tcp_skb_pcount include/net/tcp.h:798 [inline]
 [<ffffffff82430a32>] tcp_init_tso_segs net/ipv4/tcp_output.c:1631 [inline]
 [<ffffffff82430a32>] tcp_write_xmit+0x3b22/0x4680 net/ipv4/tcp_output.c:2068
 [<ffffffff82431e24>] __tcp_push_pending_frames+0xa4/0x2a0 net/ipv4/tcp_output.c:2319
 [<ffffffff82438dc6>] tcp_send_fin+0x176/0xab0 net/ipv4/tcp_output.c:2895
 [<ffffffff823f8a47>] tcp_close+0xc97/0xf60 net/ipv4/tcp.c:2112
 [<ffffffff824a0e2f>] inet_release+0xff/0x1d0 net/ipv4/af_inet.c:435
 [<ffffffff821cb4c9>] __sock_release+0xd9/0x260 net/socket.c:592
 [<ffffffff821cb669>] sock_close+0x19/0x20 net/socket.c:1050
 [<ffffffff81497845>] __fput+0x235/0x6f0 fs/file_table.c:208
 [<ffffffff81497d85>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8112fa5c>] task_work_run+0x21c/0x2d0 kernel/task_work.c:115
 [<ffffffff811021c2>] get_signal+0x1182/0x14a0 kernel/signal.c:2151
 [<ffffffff8100bf65>] do_signal+0x95/0x1840 arch/x86/kernel/signal.c:712
 [<ffffffff81003eba>] exit_to_usermode_loop+0x11a/0x160 arch/x86/entry/common.c:250
 [<ffffffff81005924>] prepare_exit_to_usermode arch/x86/entry/common.c:287 [inline]
 [<ffffffff81005924>] syscall_return_slowpath+0x254/0x2d0 arch/x86/entry/common.c:352
 [<ffffffff82713fed>] int_ret_from_sys_call+0x25/0xa3

Allocated by task 4213:
 [<ffffffff8102e566>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff8147f372>] save_stack mm/kasan/kasan.c:512 [inline]
 [<ffffffff8147f372>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff8147f372>] kasan_kmalloc.part.1+0x62/0xf0 mm/kasan/kasan.c:616
 [<ffffffff8147f5ef>] kasan_kmalloc+0xaf/0xc0 mm/kasan/kasan.c:601
 [<ffffffff8147fbb2>] kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:554
 [<ffffffff8147b2ac>] slab_post_alloc_hook mm/slub.c:1349 [inline]
 [<ffffffff8147b2ac>] slab_alloc_node mm/slub.c:2615 [inline]
 [<ffffffff8147b2ac>] slab_alloc mm/slub.c:2623 [inline]
 [<ffffffff8147b2ac>] kmem_cache_alloc+0xdc/0x2c0 mm/slub.c:2628
 [<ffffffff821ef646>] kmem_cache_alloc_node include/linux/slab.h:350 [inline]
 [<ffffffff821ef646>] __alloc_skb+0xe6/0x5b0 net/core/skbuff.c:218
 [<ffffffff823f3073>] alloc_skb_fclone include/linux/skbuff.h:856 [inline]
 [<ffffffff823f3073>] sk_stream_alloc_skb+0xa3/0x5d0 net/ipv4/tcp.c:833
 [<ffffffff823f5d01>] tcp_sendmsg+0xf81/0x2b30 net/ipv4/tcp.c:1178
 [<ffffffff824a2eb3>] inet_sendmsg+0x203/0x4d0 net/ipv4/af_inet.c:755
 [<ffffffff821d00db>] sock_sendmsg_nosec net/socket.c:638 [inline]
 [<ffffffff821d00db>] sock_sendmsg+0xbb/0x110 net/socket.c:648
 [<ffffffff821d4300>] SYSC_sendto net/socket.c:1678 [inline]
 [<ffffffff821d4300>] SyS_sendto+0x220/0x370 net/socket.c:1646
 [<ffffffff82713e61>] entry_SYSCALL_64_fastpath+0x1e/0x9a

Freed by task 4245:
 [<ffffffff8102e566>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff8147fc6c>] save_stack mm/kasan/kasan.c:512 [inline]
 [<ffffffff8147fc6c>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff8147fc6c>] kasan_slab_free+0xac/0x190 mm/kasan/kasan.c:589
 [<ffffffff8147c96e>] slab_free_hook mm/slub.c:1383 [inline]
 [<ffffffff8147c96e>] slab_free_freelist_hook mm/slub.c:1405 [inline]
 [<ffffffff8147c96e>] slab_free mm/slub.c:2859 [inline]
 [<ffffffff8147c96e>] kmem_cache_free+0xbe/0x350 mm/slub.c:2881
 [<ffffffff821e7b0f>] kfree_skbmem+0xcf/0x100 net/core/skbuff.c:635
 [<ffffffff821f4ead>] __kfree_skb+0x1d/0x20 net/core/skbuff.c:676
 [<ffffffff82432be9>] sk_wmem_free_skb include/net/sock.h:1447 [inline]
 [<ffffffff82432be9>] tcp_write_queue_purge include/net/tcp.h:1460 [inline]
 [<ffffffff82432be9>] tcp_connect_init net/ipv4/tcp_output.c:3134 [inline]
 [<ffffffff82432be9>] tcp_connect+0xae9/0x3110 net/ipv4/tcp_output.c:3273
 [<ffffffff82440af1>] tcp_v4_connect+0xf31/0x1890 net/ipv4/tcp_ipv4.c:246
 [<ffffffff824a1dc9>] __inet_stream_connect+0x2a9/0xc30 net/ipv4/af_inet.c:615
 [<ffffffff823f6787>] tcp_sendmsg_fastopen net/ipv4/tcp.c:1092 [inline]
 [<ffffffff823f6787>] tcp_sendmsg+0x1a07/0x2b30 net/ipv4/tcp.c:1112
 [<ffffffff824a2eb3>] inet_sendmsg+0x203/0x4d0 net/ipv4/af_inet.c:755
 [<ffffffff821d00db>] sock_sendmsg_nosec net/socket.c:638 [inline]
 [<ffffffff821d00db>] sock_sendmsg+0xbb/0x110 net/socket.c:648
 [<ffffffff821d4300>] SYSC_sendto net/socket.c:1678 [inline]
 [<ffffffff821d4300>] SyS_sendto+0x220/0x370 net/socket.c:1646
 [<ffffffff82713e61>] entry_SYSCALL_64_fastpath+0x1e/0x9a

The buggy address belongs to the object at ffff8801d042b180
 which belongs to the cache skbuff_fclone_cache of size 456
The buggy address is located 48 bytes inside of
 456-byte region [ffff8801d042b180, ffff8801d042b348)
The buggy address belongs to the page:
BUG: unable to handle kernel paging request at fffff94000e82150
IP: [<ffffffff81ad6a19>] memset_erms+0x9/0x10 arch/x86/lib/memset_64.S:61
PGD 3304067 PUD 3303063 PMD 3302063 PTE 8000000003305161
Oops: 0003 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 584 Comm: udevd Not tainted 4.4.164+ #123
task: ffff8801d4d34740 task.stack: ffff8801d4dc8000
RIP: 0010:[<ffffffff81ad6a19>]  [<ffffffff81ad6a19>] memset_erms+0x9/0x10 arch/x86/lib/memset_64.S:61
RSP: 0018:ffff8801d4dcfb68  EFLAGS: 00010202
RAX: 1ffffd4000e82100 RBX: fffff94000e82166 RCX: 0000000000000016
RDX: 0000000000000016 RSI: 0000000000000000 RDI: fffff94000e82150
RBP: ffff8801d4dcfb80 R08: ffff8801d4d35008 R09: fffff94000e82150
R10: 0000000000000000 R11: ffffffff831a2c38 R12: 00000000000000b0
R13: ffffea0007410b2f R14: ffffea0007410a80 R15: ffffea0007410b2f
FS:  00007fd512c5d7a0(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffff94000e82150 CR3: 00000001d4db2000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff8147f475 ffffea0007410b30 ffff8801da548000 ffff8801d4dcfbc8
 ffffffff8147f58a 00000000000000b0 024000c0d4dcfbd8 4000000000004080
 ffff8801da548000 00000000024000c0 ffffffff810cf9e6 ffffea0007410a80
Call Trace:
 [<ffffffff8147f58a>] kasan_kmalloc+0x4a/0xc0 mm/kasan/kasan.c:611
 [<ffffffff8147fbb2>] kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:554
 [<ffffffff8147b2ac>] slab_post_alloc_hook mm/slub.c:1349 [inline]
 [<ffffffff8147b2ac>] slab_alloc_node mm/slub.c:2615 [inline]
 [<ffffffff8147b2ac>] slab_alloc mm/slub.c:2623 [inline]
 [<ffffffff8147b2ac>] kmem_cache_alloc+0xdc/0x2c0 mm/slub.c:2628
 [<ffffffff810cf9e6>] dup_mmap kernel/fork.c:462 [inline]
 [<ffffffff810cf9e6>] dup_mm kernel/fork.c:985 [inline]
 [<ffffffff810cf9e6>] copy_mm kernel/fork.c:1039 [inline]
 [<ffffffff810cf9e6>] copy_process+0x42c6/0x6890 kernel/fork.c:1521
 [<ffffffff810d23c6>] _do_fork+0x146/0xdc0 kernel/fork.c:1797
 [<ffffffff810d3117>] SYSC_clone kernel/fork.c:1908 [inline]
 [<ffffffff810d3117>] SyS_clone+0x37/0x50 kernel/fork.c:1902
 [<ffffffff82713e61>] entry_SYSCALL_64_fastpath+0x1e/0x9a
Code: 48 c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 <f3> aa 4c 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 
RIP  [<ffffffff81ad6a19>] memset_erms+0x9/0x10 arch/x86/lib/memset_64.S:61
 RSP <ffff8801d4dcfb68>
CR2: fffff94000e82150
---[ end trace 6f91577b7a043829 ]---