CR3 = 0x00000000fffbc000
RSP = 0x0000000000000f7c  RIP = 0x0000000000000408
RFLAGS=0x00000046         DR7 = 0x0000000000000400
Sysenter RSP=0000000000000f80 CS:RIP=0050:0000000000002810
==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:347 [inline]
BUG: KASAN: slab-out-of-bounds in pdu_read+0x8a/0xc0 net/9p/protocol.c:64
Read of size 12140 at addr ffff88804996222d by task syz-executor.2/8556

CPU: 0 PID: 8556 Comm: syz-executor.2 Not tainted 4.14.176-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x13e/0x194 lib/dump_stack.c:58
 print_address_description.cold+0x7c/0x1e2 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0xa9/0x2ae mm/kasan/report.c:393
 memcpy+0x20/0x50 mm/kasan/kasan.c:302
 memcpy include/linux/string.h:347 [inline]
 pdu_read+0x8a/0xc0 net/9p/protocol.c:64
 p9pdu_vreadf net/9p/protocol.c:167 [inline]
 p9pdu_readf+0x379/0x1790 net/9p/protocol.c:540
 p9_client_version net/9p/client.c:990 [inline]
 p9_client_create+0xa1f/0x10f0 net/9p/client.c:1088
 v9fs_session_init+0x1dc/0x1620 fs/9p/v9fs.c:422
IPVS: ftp: loaded support on port[0] = 21
 v9fs_mount+0x79/0x850 fs/9p/vfs_super.c:135
 mount_fs+0x92/0x2a0 fs/super.c:1237
 vfs_kern_mount.part.0+0x5b/0x3c0 fs/namespace.c:1046
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2549 [inline]
 do_mount+0x3c9/0x24f0 fs/namespace.c:2879
 SYSC_mount fs/namespace.c:3095 [inline]
 SyS_mount+0xa8/0x120 fs/namespace.c:3072
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c889
RSP: 002b:00007fa4d68cac78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fa4d68cb6d4 RCX: 000000000045c889
RDX: 0000000020000180 RSI: 0000000020000500 RDI: 0000000000000000
RBP: 000000000076bf00 R08: 0000000020000700 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000074c R14: 00000000004ca0ed R15: 000000000076bf0c

Allocated by task 8556:
 save_stack+0x32/0xa0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc mm/kasan/kasan.c:551 [inline]
 kasan_kmalloc+0xbf/0xe0 mm/kasan/kasan.c:529
 __do_kmalloc mm/slab.c:3720 [inline]
 __kmalloc+0x15b/0x7c0 mm/slab.c:3729
 kmalloc include/linux/slab.h:493 [inline]
 p9_fcall_alloc+0x19/0x90 net/9p/client.c:242
 p9_tag_alloc net/9p/client.c:312 [inline]
 p9_client_prepare_req.part.0+0x72f/0xa90 net/9p/client.c:728
 p9_client_prepare_req net/9p/client.c:718 [inline]
 p9_client_rpc+0x170/0x1180 net/9p/client.c:763
 p9_client_version net/9p/client.c:980 [inline]
 p9_client_create+0x997/0x10f0 net/9p/client.c:1088
 v9fs_session_init+0x1dc/0x1620 fs/9p/v9fs.c:422
 v9fs_mount+0x79/0x850 fs/9p/vfs_super.c:135
 mount_fs+0x92/0x2a0 fs/super.c:1237
 vfs_kern_mount.part.0+0x5b/0x3c0 fs/namespace.c:1046
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2549 [inline]
 do_mount+0x3c9/0x24f0 fs/namespace.c:2879
 SYSC_mount fs/namespace.c:3095 [inline]
 SyS_mount+0xa8/0x120 fs/namespace.c:3072
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff888049962200
 which belongs to the cache kmalloc-16384 of size 16384
The buggy address is located 45 bytes inside of
 16384-byte region [ffff888049962200, ffff888049966200)
The buggy address belongs to the page:
page:ffffea0001265800 count:1 mapcount:0 mapping:ffff888049962200 index:0x0 compound_mapcount: 0
flags: 0xfffe0000008100(slab|head)
raw: 00fffe0000008100 ffff888049962200 0000000000000000 0000000100000001
raw: ffffea0001267a20 ffffea0001266420 ffff88812fe55200 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888049964100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888049964180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888049964200: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc
                               ^
 ffff888049964280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888049964300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
CS:   sel=0x0000, attr=0x08081, limit=0x00000000, base=0x0000000000000000
DS:   sel=0x0000, attr=0x10000, limit=0x00100000, base=0x0000000000000000
minix_free_inode: bit 1 already cleared
SS:   sel=0x0000, attr=0x08085, limit=0x00000000, base=0x0000000000000000
ES:   sel=0x0003, attr=0x10000, limit=0x00000000, base=0x0000000000000000
FS:   sel=0x0000, attr=0x10000, limit=0x00000000, base=0x0000000000000000
kauditd_printk_skb: 2 callbacks suppressed
audit: type=1800 audit(1586895964.019:26): pid=8567 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed(directio)" comm="syz-executor.1" name="file0" dev="sda1" ino=15839 res=0
minix_free_inode: bit 1 already cleared
MINIX-fs: mounting unchecked file system, running fsck is recommended
GS:   sel=0x0000, attr=0x10000, limit=0x00003000, base=0x0000000000000000
GDTR:                           limit=0x00000000, base=0x0000000000000000
LDTR: sel=0x0000, attr=0x10000, limit=0x00000002, base=0x0000000000000000
IDTR:                           limit=0x00000000, base=0x0000000000000000
TR:   sel=0x0000, attr=0x10000, limit=0x00000000, base=0x0000000000000000
jfs: Unrecognized mount option "integraty" or missing value
EFER =     0x0000000000000000  PAT = 0x0007040600070406
DebugCtl = 0x0000000000000000  DebugExceptions = 0x0000000000000000
Interruptibility = 00000000  ActivityState = 00000000
*** Host State ***
RIP = 0xffffffff8116f8df  RSP = 0xffff888049e4f9b0
CS=0010 SS=0018 DS=0000 ES=0000 FS=0000 GS=0000 TR=0040
FSBase=00007f1858a73700 GSBase=ffff8880aea00000 TRBase=fffffe0000003000
GDTBase=fffffe0000001000 IDTBase=fffffe0000000000
CR0=0000000080050033 CR3=00000000938b0000 CR4=00000000001426f0
Sysenter RSP=fffffe0000002200 CS:RIP=0010:ffffffff866018a0
EFER = 0x0000000000000d01  PAT = 0x0407050600070106
*** Control State ***
PinBased=0000003f CPUBased=b699edfa SecondaryExec=000000ea
EntryControls=0000d1ff ExitControls=002fefff
ExceptionBitmap=00060042 PFECmask=00000000 PFECmatch=00000000
VMEntry: intr_info=00000000 errcode=00000000 ilen=00000000
VMExit: intr_info=00000000 errcode=00000000 ilen=00000001
        reason=80000021 qualification=0000000000000000
IDTVectoring: info=00000000 errcode=00000000
TSC Offset = 0xffffff8f97940339
EPT pointer = 0x000000009308d01e
Virtual processor ID = 0x0001