KASAN: use-after-free Write in diWrite

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3f8a27f9e27b Linux 4.19.211
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10ea8752880000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9277b418617afe
dashboard link: https://syzkaller.appspot.com/bug?extid=8b6aac199558389f3f80
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/98c0bdb4abb3/disk-3f8a27f9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ea228ff02669/vmlinux-3f8a27f9.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8b6aac...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in memcpy include/linux/string.h:377 [inline]
BUG: KASAN: use-after-free in diWrite+0xbf2/0x13c0 fs/jfs/jfs_imap.c:764
Write of size 32 at addr ffff88809e6e4260 by task syz-executor.2/24504

CPU: 1 PID: 24504 Comm: syz-executor.2 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
kasan_report+0x8f/0xa0 mm/kasan/report.c:412
memcpy+0x35/0x50 mm/kasan/kasan.c:303
memcpy include/linux/string.h:377 [inline]
diWrite+0xbf2/0x13c0 fs/jfs/jfs_imap.c:764
txCommit+0x5f8/0x39e0 fs/jfs/jfs_txnmgr.c:1263
jfs_create.part.0+0x76b/0x880 fs/jfs/namei.c:169
jfs_create+0x3f/0x60 fs/jfs/namei.c:90
lookup_open+0x893/0x1a20 fs/namei.c:3235
do_last fs/namei.c:3327 [inline]
path_openat+0x1094/0x2df0 fs/namei.c:3537
do_filp_open+0x18c/0x3f0 fs/namei.c:3567
do_sys_open+0x3b3/0x520 fs/open.c:1085
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f87124875a9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8710db8168 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f87125a8120 RCX: 00007f87124875a9
RDX: 0000000000000000 RSI: 0000000000101042 RDI: 0000000020000040
RBP: 00007f87124e2580 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc92f99e6f R14: 00007f8710db8300 R15: 0000000000022000

Allocated by task 24014:
kmem_cache_alloc+0x122/0x370 mm/slab.c:3559
getname_flags+0xce/0x590 fs/namei.c:140
do_sys_open+0x26c/0x520 fs/open.c:1079
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 24014:
__cache_free mm/slab.c:3503 [inline]
kmem_cache_free+0x7f/0x260 mm/slab.c:3765
putname+0xe1/0x120 fs/namei.c:261
do_sys_open+0x2ba/0x520 fs/open.c:1094
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff88809e6e4080
which belongs to the cache names_cache of size 4096
The buggy address is located 480 bytes inside of
4096-byte region [ffff88809e6e4080, ffff88809e6e5080)
The buggy address belongs to the page:
page:ffffea000279b900 count:1 mapcount:0 mapping:ffff88823b843380 index:0x0 compound_mapcount: 0
flags: 0xfff00000008100(slab|head)
raw: 00fff00000008100 ffffea0002cc2288 ffffea0001429788 ffff88823b843380
raw: 0000000000000000 ffff88809e6e4080 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff88809e6e4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88809e6e4180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88809e6e4200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88809e6e4280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88809e6e4300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 3f8a27f9e27b Linux 4.19.211
git tree: linux-4.19.y

console output: https://syzkaller.appspot.com/x/log.txt?x=1638134e880000

kernel config: https://syzkaller.appspot.com/x/.config?x=9b9277b418617afe
dashboard link: https://syzkaller.appspot.com/bug?extid=8b6aac199558389f3f80
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11d49cd2880000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/98c0bdb4abb3/disk-3f8a27f9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ea228ff02669/vmlinux-3f8a27f9.xz

mounted in repro #1: https://storage.googleapis.com/syzbot-assets/b7fe53f65137/mount_0.gz
mounted in repro #2: https://storage.googleapis.com/syzbot-assets/9d2d975cd171/mount_7.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8b6aac...@syzkaller.appspotmail.com

wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50
IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready
==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:377 [inline]
BUG: KASAN: slab-out-of-bounds in diWrite+0xbf2/0x13c0 fs/jfs/jfs_imap.c:764
Write of size 32 at addr ffff8880a636e260 by task syz-executor.4/10531

CPU: 0 PID: 10531 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
kasan_report+0x8f/0xa0 mm/kasan/report.c:412
memcpy+0x35/0x50 mm/kasan/kasan.c:303
memcpy include/linux/string.h:377 [inline]
diWrite+0xbf2/0x13c0 fs/jfs/jfs_imap.c:764
txCommit+0x5f8/0x39e0 fs/jfs/jfs_txnmgr.c:1263
jfs_create.part.0+0x76b/0x880 fs/jfs/namei.c:169
jfs_create+0x3f/0x60 fs/jfs/namei.c:90
lookup_open+0x893/0x1a20 fs/namei.c:3235
do_last fs/namei.c:3327 [inline]
path_openat+0x1094/0x2df0 fs/namei.c:3537
do_filp_open+0x18c/0x3f0 fs/namei.c:3567
do_sys_open+0x3b3/0x520 fs/open.c:1085
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe

RIP: 0033:0x7fc560c4d5a9

Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48

RSP: 002b:00007fc56039f168 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fc560d6e050 RCX: 00007fc560c4d5a9

RDX: 0000000000000000 RSI: 0000000000101042 RDI: 0000000020000040

RBP: 00007fc560ca8580 R08: 0000000000000000 R09: 0000000000000000

R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000

R13: 00007ffcad665e5f R14: 00007fc56039f300 R15: 0000000000022000

Allocated by task 4704:

kmem_cache_alloc+0x122/0x370 mm/slab.c:3559
getname_flags+0xce/0x590 fs/namei.c:140

user_path_at_empty+0x2a/0x50 fs/namei.c:2609
user_path_at include/linux/namei.h:57 [inline]
do_faccessat+0x248/0x7a0 fs/open.c:397
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 4704:

__cache_free mm/slab.c:3503 [inline]
kmem_cache_free+0x7f/0x260 mm/slab.c:3765
putname+0xe1/0x120 fs/namei.c:261

filename_lookup+0x3d0/0x5a0 fs/namei.c:2358
user_path_at include/linux/namei.h:57 [inline]
do_faccessat+0x248/0x7a0 fs/open.c:397
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8880a636e9c0

which belongs to the cache names_cache of size 4096

The buggy address is located 1888 bytes to the left of
4096-byte region [ffff8880a636e9c0, ffff8880a636f9c0)

The buggy address belongs to the page:

page:ffffea000298db80 count:1 mapcount:0 mapping:ffff88823b843380 index:0x0 compound_mapcount: 0
flags: 0xfff00000008100(slab|head)
raw: 00fff00000008100 ffffea0002990c08 ffffea00023e4d08 ffff88823b843380
raw: 0000000000000000 ffff8880a636e9c0 0000000100000001 0000000000000000

page dumped because: kasan: bad access detected

Memory state around the buggy address:

ffff8880a636e100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8880a636e180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880a636e200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff8880a636e280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8880a636e300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================