KASAN: out-of-bounds Write in tls_push_record

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 9f31eb60 Linux 4.19.53
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=164a2ad6a00000
kernel config: https://syzkaller.appspot.com/x/.config?x=7a36b9832db62b25
dashboard link: https://syzkaller.appspot.com/bug?extid=d79ed422dc06ae26a022
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+d79ed4...@syzkaller.appspotmail.com

TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending
cookies. Check SNMP counters.
*** Guest State ***
CR0: actual=0x0000000000000020, shadow=0x0000000000000000,
gh_mask=fffffffffffffff7
CR4: actual=0x00000000000120e0, shadow=0x00000000000100a0,
gh_mask=ffffffffffffe871
==================================================================
BUG: KASAN: out-of-bounds in tls_fill_prepend include/net/tls.h:372 [inline]
BUG: KASAN: out-of-bounds in tls_push_record+0x102a/0x13a0
net/tls/tls_sw.c:220
Write of size 1 at addr ffff88805d598000 by task syz-executor.1/24945

CPU: 1 PID: 24945 Comm: syz-executor.1 Not tainted 4.19.53+ #25
CR3 = 0x0000000000000000
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
PDPTR0 = 0x0000000000000000 PDPTR1 = 0x0000000000000000
print_address_description.cold+0x7c/0x20d mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:354 [inline]
kasan_report mm/kasan/report.c:412 [inline]
kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396
__asan_report_store1_noabort+0x17/0x20 mm/kasan/report.c:435
tls_fill_prepend include/net/tls.h:372 [inline]
tls_push_record+0x102a/0x13a0 net/tls/tls_sw.c:220
tls_sw_push_pending_record+0x23/0x30 net/tls/tls_sw.c:257
tls_handle_open_record net/tls/tls_main.c:156 [inline]
tls_sk_proto_close+0x5bb/0xa20 net/tls/tls_main.c:271
inet_release+0xff/0x1e0 net/ipv4/af_inet.c:428
inet6_release+0x53/0x80 net/ipv6/af_inet6.c:472
__sock_release+0xce/0x2a0 net/socket.c:579
sock_close+0x1b/0x30 net/socket.c:1140
__fput+0x2dd/0x8b0 fs/file_table.c:278
____fput+0x16/0x20 fs/file_table.c:309
task_work_run+0x145/0x1c0 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:193 [inline]
exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:167
prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
do_syscall_64+0x53d/0x620 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4592c9
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fc97edfac78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: 0000000000004000 RBX: 00007fc97edfac90 RCX: 00000000004592c9
RDX: ffffffffffffffc1 RSI: 00000000200005c0 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 1201000000003618
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc97edfb6d4
R13: 00000000004c707f R14: 00000000004dc260 R15: 0000000000000006

The buggy address belongs to the page:
page:ffffea0001756600 count:1 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x1fffc0000000000()
raw: 01fffc0000000000 dead000000000100 dead000000000200 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff88805d597f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88805d597f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ffff88805d598000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
^
ffff88805d598080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88805d598100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
PDPTR2 = 0x0000000000000000 PDPTR3 = 0x0000000000000000
RSP = 0x0000000000000000 RIP = 0x000000000000fff0


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.