program syz-executor5 not setting count and/or reply_len properly
==================================================================
BUG: KASAN: wild-memory-access on address ffe708746e2dd000
Read of size 183 by task syz-executor5/8533
CPU: 0 PID: 8533 Comm: syz-executor5 Not tainted 4.9.56-g05c85a6 #64
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801a9d5f9e8 ffffffff81d93979 ffe708746e2dd000 00000000000000b7
 0000000000000000 ffff8801a5ea9360 ffe708746e2dd000 ffff8801a9d5fa70
 ffffffff8153d5cf 0000000000000000 0000000000000001 ffffffff8266525b
Call Trace:
 [<ffffffff81d93979>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d93979>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8153d5cf>] kasan_report_error mm/kasan/report.c:284 [inline]
 [<ffffffff8153d5cf>] kasan_report.part.1+0x40f/0x500 mm/kasan/report.c:309
 [<ffffffff8153d9a0>] kasan_report+0x20/0x30 mm/kasan/report.c:296
 [<ffffffff8153c2e7>] check_memory_region_inline mm/kasan/kasan.c:308 [inline]
 [<ffffffff8153c2e7>] check_memory_region+0x137/0x190 mm/kasan/kasan.c:315
 [<ffffffff8153c351>] kasan_check_read+0x11/0x20 mm/kasan/kasan.c:320
 [<ffffffff8266525b>] __copy_to_user arch/x86/include/asm/uaccess_64.h:182 [inline]
 [<ffffffff8266525b>] sg_read_oxfer drivers/scsi/sg.c:1978 [inline]
 [<ffffffff8266525b>] sg_read+0x124b/0x1400 drivers/scsi/sg.c:520
 [<ffffffff8156bc81>] do_loop_readv_writev.part.17+0x141/0x1e0 fs/read_write.c:714
 [<ffffffff8156fa50>] do_loop_readv_writev fs/read_write.c:880 [inline]
 [<ffffffff8156fa50>] do_readv_writev+0x520/0x750 fs/read_write.c:874
 [<ffffffff8156fd04>] vfs_readv+0x84/0xc0 fs/read_write.c:898
 [<ffffffff8156fe26>] do_readv+0xe6/0x250 fs/read_write.c:924
 [<ffffffff815732a7>] SYSC_readv fs/read_write.c:1011 [inline]
 [<ffffffff815732a7>] SyS_readv+0x27/0x30 fs/read_write.c:1008
 [<ffffffff838ad085>] entry_SYSCALL_64_fastpath+0x23/0xc6
==================================================================
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 8533 Comm: syz-executor5 Tainted: G    B           4.9.56-g05c85a6 #64
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801cf68e000 task.stack: ffff8801a9d58000
RIP: 0010:[<ffffffff8144e4b1>]  [<ffffffff8144e4b1>] __read_once_size include/linux/compiler.h:243 [inline]
RIP: 0010:[<ffffffff8144e4b1>]  [<ffffffff8144e4b1>] atomic_read arch/x86/include/asm/atomic.h:26 [inline]
RIP: 0010:[<ffffffff8144e4b1>]  [<ffffffff8144e4b1>] page_ref_count include/linux/page_ref.h:66 [inline]
RIP: 0010:[<ffffffff8144e4b1>]  [<ffffffff8144e4b1>] put_page_testzero include/linux/mm.h:445 [inline]
RIP: 0010:[<ffffffff8144e4b1>]  [<ffffffff8144e4b1>] __free_pages+0x21/0x80 mm/page_alloc.c:3901
RSP: 0018:ffff8801a9d5fb00  EFLAGS: 00010a07
RAX: dffffc0000000000 RBX: dead4ead00000000 RCX: ffffc90003052000
RDX: 1bd5a9d5a0000003 RSI: 0000000000000000 RDI: dead4ead0000001c
RBP: ffff8801a9d5fb10 R08: ffffed0034bd5240 R09: 0000000000000000
R10: fffc9dc000000000 R11: ffffed0034bd5240 R12: 0000000000000004
R13: 0000000000000020 R14: ffff8801c668a100 R15: dffffc0000000000
FS:  00007f60d8b48700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f336bba5db8 CR3: 00000001c98f8000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 0000000000000000 ffff8801c668a258 ffff8801a9d5fb70 ffffffff82662851
 ffff8801c668a270 ffffed0038cd144b ffffed0038cd144e ffff8801c668a268
 dead4ead00000000 ffff8801c668a240 0000000000000000 0000000000000000
Call Trace:
 [<ffffffff82662851>] sg_remove_scat.isra.20+0x1c1/0x2d0 drivers/scsi/sg.c:1954
 [<ffffffff82662c15>] sg_finish_rem_req+0x2b5/0x340 drivers/scsi/sg.c:1836
 [<ffffffff8266492c>] sg_read+0x91c/0x1400 drivers/scsi/sg.c:527
 [<ffffffff8156d893>] __vfs_read+0x103/0x670 fs/read_write.c:452
 [<ffffffff8156ee27>] vfs_read+0x107/0x330 fs/read_write.c:475
 [<ffffffff81572ac9>] SYSC_read fs/read_write.c:591 [inline]
 [<ffffffff81572ac9>] SyS_read+0xd9/0x1b0 fs/read_write.c:584
 [<ffffffff838ad085>] entry_SYSCALL_64_fastpath+0x23/0xc6
Code: ff 66 0f 1f 84 00 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 53 48 89 fb 48 83 c7 1c 48 89 fa 48 83 ec 08 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 3d 
RIP  [<ffffffff8144e4b1>] __read_once_size include/linux/compiler.h:243 [inline]
RIP  [<ffffffff8144e4b1>] atomic_read arch/x86/include/asm/atomic.h:26 [inline]
RIP  [<ffffffff8144e4b1>] page_ref_count include/linux/page_ref.h:66 [inline]
RIP  [<ffffffff8144e4b1>] put_page_testzero include/linux/mm.h:445 [inline]
RIP  [<ffffffff8144e4b1>] __free_pages+0x21/0x80 mm/page_alloc.c:3901
 RSP <ffff8801a9d5fb00>
---[ end trace ac9f2f2435c7cef8 ]---