syzbot


KASAN: wild-memory-access Read of size 8

Status: closed as invalid on 2017/10/18 09:01
First crash: 2388d, last: 2374d

Sample crash report:
IPVS: length: 24 != 49176
==================================================================
BUG: KASAN: wild-memory-access on address ffe708746e9a1000
Read of size 8 by task syz-executor1/10704
CPU: 1 PID: 10704 Comm: syz-executor1 Not tainted 4.9.56-g5c73594 #66
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d973f9e8 ffffffff81d93999 ffe708746e9a1000 0000000000000008
 0000000000000000 ffff8801c64367e0 ffe708746e9a1000 ffff8801d973fa70
 ffffffff8153d5cf 0000000000000000 0000000000000001 ffffffff8266527b
Call Trace:
 [<ffffffff81d93999>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d93999>] 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
 [<ffffffff8266527b>] __copy_to_user arch/x86/include/asm/uaccess_64.h:182 [inline]
 [<ffffffff8266527b>] sg_read_oxfer drivers/scsi/sg.c:1978 [inline]
 [<ffffffff8266527b>] 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
==================================================================
IPVS: length: 24 != 49176
sg_write: data in/out 93/34 bytes for SCSI command 0xfc-- guessing data in;
   program syz-executor1 not setting count and/or reply_len properly
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: 1 PID: 10732 Comm: syz-executor1 Tainted: G    B           4.9.56-g5c73594 #66
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d0f0b000 task.stack: ffff8801cbb00000
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:ffff8801cbb079b0  EFLAGS: 00010a07
RAX: dffffc0000000000 RBX: dead4ead00000000 RCX: ffffc900041f8000
RDX: 1bd5a9d5a0000003 RSI: 0000000000000001 RDI: dead4ead0000001c
RBP: ffff8801cbb079c0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 1ffff10039760f18 R12: 0000000000000004
R13: 0000000000000020 R14: ffff8801abb78000 R15: dffffc0000000000
FS:  00007fac56105700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6ab6833db8 CR3: 00000001a8489000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801d0f0b000 ffff8801abb78158 ffff8801cbb07a20 ffffffff82662871
 ffff8801abb78170 ffffed003576f02b ffffed003576f02e ffff8801abb78168
 dead4ead00000000 ffff8801abb78140 0000000000000000 0000000000000000
Call Trace:
 [<ffffffff82662871>] sg_remove_scat.isra.20+0x1c1/0x2d0 drivers/scsi/sg.c:1954
 [<ffffffff82662c35>] sg_finish_rem_req+0x2b5/0x340 drivers/scsi/sg.c:1836
 [<ffffffff82662cf9>] sg_new_read.isra.21+0x39/0x3e0 drivers/scsi/sg.c:567
 [<ffffffff826648d6>] sg_read+0x8a6/0x1400 drivers/scsi/sg.c:456
 [<ffffffff810002b8>] ? 0xffffffff810002b8
 [<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
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 <ffff8801cbb079b0>
---[ end trace 44210310ba744856 ]---

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2017/10/15 04:15 https://android.googlesource.com/kernel/common android-4.9 5c73594e214f b69d27d1 .config console log report ci-android-49-kasan-gce
2017/10/01 07:23 https://android.googlesource.com/kernel/common android-4.9 9b2b08179641 c26ea367 .config console log report ci-android-49-kasan-gce
* Struck through repros no longer work on HEAD.