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: slab-out-of-bounds in strlen+0x91/0xa0 lib/string.c:481
Read of size 1 at addr ffff8801b78f4740 by task syz-executor676/3790

CPU: 0 PID: 3790 Comm: syz-executor676 Not tainted 4.9.96-g71fce1e #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801b6b0f978 ffffffff81eb0b69 ffffea0006de3d00 ffff8801b78f4740
 0000000000000000 ffff8801b78f4740 ffff8801b78f4738 ffff8801b6b0f9b0
 ffffffff8156540b ffff8801b78f4740 0000000000000001 0000000000000000
Call Trace:
 [<ffffffff81eb0b69>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb0b69>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8156540b>] print_address_description+0x6c/0x234 mm/kasan/report.c:256
 [<ffffffff81565815>] kasan_report_error mm/kasan/report.c:355 [inline]
 [<ffffffff81565815>] kasan_report.cold.6+0x242/0x2fe mm/kasan/report.c:412
 [<ffffffff81539434>] __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430
 [<ffffffff81ecdeb1>] strlen+0x91/0xa0 lib/string.c:481
 [<ffffffff815a6064>] getname_kernel+0x24/0x340 fs/namei.c:215
 [<ffffffff815a7684>] kern_path_mountpoint+0x24/0x70 fs/namei.c:2754
 [<ffffffff81901dce>] find_autofs_mount.isra.4+0x8e/0x200 fs/autofs4/dev-ioctl.c:213
 [<ffffffff81902c03>] autofs_dev_ioctl_open_mountpoint fs/autofs4/dev-ioctl.c:258 [inline]
 [<ffffffff81902c03>] autofs_dev_ioctl_openmount+0x153/0x2d0 fs/autofs4/dev-ioctl.c:303
 [<ffffffff81901b4b>] _autofs_dev_ioctl+0x4fb/0x690 fs/autofs4/dev-ioctl.c:699
 [<ffffffff81901cfb>] autofs_dev_ioctl+0x1b/0x30 fs/autofs4/dev-ioctl.c:714
 [<ffffffff815b051c>] vfs_ioctl fs/ioctl.c:43 [inline]
 [<ffffffff815b051c>] file_ioctl fs/ioctl.c:493 [inline]
 [<ffffffff815b051c>] do_vfs_ioctl+0x1ac/0x11a0 fs/ioctl.c:677
 [<ffffffff815b159f>] SYSC_ioctl fs/ioctl.c:694 [inline]
 [<ffffffff815b159f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f3313>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Allocated by task 3790:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57
 save_stack+0x43/0xd0 mm/kasan/kasan.c:505
 set_track mm/kasan/kasan.c:517 [inline]
 kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:609
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:547
 slab_post_alloc_hook mm/slab.h:417 [inline]
 slab_alloc_node mm/slub.c:2715 [inline]
 slab_alloc mm/slub.c:2723 [inline]
 __kmalloc_track_caller+0xdc/0x2b0 mm/slub.c:4232
 memdup_user+0x2c/0xb0 mm/util.c:161
 copy_dev_ioctl fs/autofs4/dev-ioctl.c:110 [inline]
 _autofs_dev_ioctl+0x13a/0x690 fs/autofs4/dev-ioctl.c:645
 autofs_dev_ioctl+0x1b/0x30 fs/autofs4/dev-ioctl.c:714
 vfs_ioctl fs/ioctl.c:43 [inline]
 file_ioctl fs/ioctl.c:493 [inline]
 do_vfs_ioctl+0x1ac/0x11a0 fs/ioctl.c:677
 SYSC_ioctl fs/ioctl.c:694 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685
 do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Freed by task 2441:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57
 save_stack+0x43/0xd0 mm/kasan/kasan.c:505
 set_track mm/kasan/kasan.c:517 [inline]
 kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:582
 slab_free_hook mm/slub.c:1355 [inline]
 slab_free_freelist_hook mm/slub.c:1377 [inline]
 slab_free mm/slub.c:2958 [inline]
 kfree+0xfb/0x310 mm/slub.c:3878
 single_release+0x88/0xb0 fs/seq_file.c:609
 __fput+0x263/0x700 fs/file_table.c:208
 ____fput+0x15/0x20 fs/file_table.c:244
 task_work_run+0x10c/0x180 kernel/task_work.c:116
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0xfc/0x120 arch/x86/entry/common.c:161
 prepare_exit_to_usermode arch/x86/entry/common.c:191 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:260 [inline]
 do_syscall_64+0x364/0x490 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_swapgs+0x5d/0xdb

The buggy address belongs to the object at ffff8801b78f4720
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes to the right of
 32-byte region [ffff8801b78f4720, ffff8801b78f4740)
The buggy address belongs to the page:
page:ffffea0006de3d00 count:1 mapcount:0 mapping:          (null) index:0x0
flags: 0x8000000000000080(slab)
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b78f4600: fb fb fb fb fc fc fb fb fb fb fc fc fb fb fb fb
 ffff8801b78f4680: fc fc fb fb fb fb fc fc fb fb fb fb fc fc fb fb
>ffff8801b78f4700: fb fb fc fc 00 00 00 00 fc fc fb fb fb fb fc fc
                                           ^
 ffff8801b78f4780: 00 00 00 00 fc fc fb fb fb fb fc fc fb fb fb fb
 ffff8801b78f4800: fc fc fb fb fb fb fc fc fb fb fb fb fc fc fb fb
==================================================================