syzbot

random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
==================================================================
BUG: KASAN: use-after-free in tls_sk_proto_close+0x8ab/0x9c0 net/tls/tls_main.c:297
Read of size 1 at addr ffff8801b4b4c258 by task syz-executor486/4512

CPU: 1 PID: 4512 Comm: syz-executor486 Not tainted 4.17.0-rc3+ #34
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+0x1b9/0x294 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430
 tls_sk_proto_close+0x8ab/0x9c0 net/tls/tls_main.c:297
 inet_release+0x104/0x1f0 net/ipv4/af_inet.c:427
 inet6_release+0x50/0x70 net/ipv6/af_inet6.c:460
 sock_release+0x96/0x1b0 net/socket.c:594
 sock_close+0x16/0x20 net/socket.c:1149
 __fput+0x34d/0x890 fs/file_table.c:209
 ____fput+0x15/0x20 fs/file_table.c:243
 task_work_run+0x1e4/0x290 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x1aee/0x2730 kernel/exit.c:865
 do_group_exit+0x16f/0x430 kernel/exit.c:968
 __do_sys_exit_group kernel/exit.c:979 [inline]
 __se_sys_exit_group kernel/exit.c:977 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:977
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x43eb58
RSP: 002b:00007ffe5de43c38 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043eb58
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004be500 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 0000000020000100 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006cc160 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 4512:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
 kmem_cache_alloc_trace+0x152/0x780 mm/slab.c:3620
 kmalloc include/linux/slab.h:512 [inline]
 kzalloc include/linux/slab.h:701 [inline]
 create_ctx net/tls/tls_main.c:521 [inline]
 tls_init+0x1f9/0xb00 net/tls/tls_main.c:633
 tcp_set_ulp+0x1bc/0x520 net/ipv4/tcp_ulp.c:153
 do_tcp_setsockopt.isra.39+0x44a/0x2600 net/ipv4/tcp.c:2588
 tcp_setsockopt+0xc1/0xe0 net/ipv4/tcp.c:2893
 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3039
 __sys_setsockopt+0x1bd/0x390 net/socket.c:1903
 __do_sys_setsockopt net/socket.c:1914 [inline]
 __se_sys_setsockopt net/socket.c:1911 [inline]
 __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1911
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 4512:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xd9/0x260 mm/slab.c:3813
 tls_sw_free_resources+0x2a3/0x360 net/tls/tls_sw.c:1037
 tls_sk_proto_close+0x67c/0x9c0 net/tls/tls_main.c:288
 inet_release+0x104/0x1f0 net/ipv4/af_inet.c:427
 inet6_release+0x50/0x70 net/ipv6/af_inet6.c:460
 sock_release+0x96/0x1b0 net/socket.c:594
 sock_close+0x16/0x20 net/socket.c:1149
 __fput+0x34d/0x890 fs/file_table.c:209
 ____fput+0x15/0x20 fs/file_table.c:243
 task_work_run+0x1e4/0x290 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x1aee/0x2730 kernel/exit.c:865
 do_group_exit+0x16f/0x430 kernel/exit.c:968
 __do_sys_exit_group kernel/exit.c:979 [inline]
 __se_sys_exit_group kernel/exit.c:977 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:977
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801b4b4c200
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 88 bytes inside of
 256-byte region [ffff8801b4b4c200, ffff8801b4b4c300)
The buggy address belongs to the page:
page:ffffea0006d2d300 count:1 mapcount:0 mapping:ffff8801b4b4c0c0 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801b4b4c0c0 0000000000000000 000000010000000c
raw: ffffea0006be3320 ffff8801da801648 ffff8801da8007c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b4b4c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801b4b4c180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff8801b4b4c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff8801b4b4c280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801b4b4c300: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
==================================================================