KASAN: slab-out-of-bounds Read in dbAdjTree

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 9d5c0b3a8e1a Linux 4.14.295
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=169e4532880000
kernel config: https://syzkaller.appspot.com/x/.config?x=746c079015a92425
dashboard link: https://syzkaller.appspot.com/bug?extid=2aa0d1c312850487b23f
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=112c3648880000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=110e9148880000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ed6fcf5895a2/disk-9d5c0b3a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/341aa3534116/vmlinux-9d5c0b3a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2aa0d1...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: slab-out-of-bounds in dbAdjTree+0x20d/0x280 fs/jfs/jfs_dmap.c:2918
Read of size 1 at addr ffff8880af2dd078 by task syz-executor423/7959

CPU: 1 PID: 7959 Comm: syz-executor423 Not tainted 4.14.295-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x281 lib/dump_stack.c:58
print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351
kasan_report mm/kasan/report.c:409 [inline]
__asan_report_load1_noabort+0x68/0x70 mm/kasan/report.c:427
dbAdjTree+0x20d/0x280 fs/jfs/jfs_dmap.c:2918
dbSplit+0xeb/0x130 fs/jfs/jfs_dmap.c:2690
dbAllocBits+0x10b/0x4a0 fs/jfs/jfs_dmap.c:2239
dbAllocDmap+0x5f/0x100 fs/jfs/jfs_dmap.c:2080
dbAllocNear fs/jfs/jfs_dmap.c:1309 [inline]
dbAlloc+0x679/0x980 fs/jfs/jfs_dmap.c:826
diNewExt+0x5b0/0x1780 fs/jfs/jfs_imap.c:2272
diAllocExt fs/jfs/jfs_imap.c:1966 [inline]
diAllocAG+0x14ee/0x2110 fs/jfs/jfs_imap.c:1683
diAlloc+0x69d/0x1230 fs/jfs/jfs_imap.c:1604
ialloc+0x7b/0x940 fs/jfs/jfs_inode.c:70
jfs_mkdir.part.0+0xfd/0x7e0 fs/jfs/namei.c:238
jfs_mkdir+0x35/0x50 fs/jfs/namei.c:223
vfs_mkdir+0x463/0x6e0 fs/namei.c:3851
SYSC_mkdirat fs/namei.c:3874 [inline]
SyS_mkdirat+0x1fd/0x270 fs/namei.c:3858
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f24d3892e49
RSP: 002b:00007ffc991e54c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f24d3892e49
RDX: 00007f24d38513e3 RSI: 0000000000000000 RDI: 00000000200052c0
RBP: 00007f24d38526b0 R08: 00005555574f02c0 R09: 0000000000000000
R10: 00007ffc991e5390 R11: 0000000000000246 R12: 00000000f8008000
R13: 0000000000000000 R14: 00080000000000fc R15: 0000000000000000

Allocated by task 4632:
save_stack mm/kasan/kasan.c:447 [inline]
set_track mm/kasan/kasan.c:459 [inline]
kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551
__do_kmalloc mm/slab.c:3720 [inline]
__kmalloc+0x15a/0x400 mm/slab.c:3729
kmalloc include/linux/slab.h:493 [inline]
kernfs_fop_write+0x2fe/0x440 fs/kernfs/file.c:293
__vfs_write+0xe4/0x630 fs/read_write.c:480
vfs_write+0x17f/0x4d0 fs/read_write.c:544
SYSC_write fs/read_write.c:590 [inline]
SyS_write+0xf2/0x210 fs/read_write.c:582
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb

Freed by task 4632:
save_stack mm/kasan/kasan.c:447 [inline]
set_track mm/kasan/kasan.c:459 [inline]
kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524
__cache_free mm/slab.c:3496 [inline]
kfree+0xc9/0x250 mm/slab.c:3815
kernfs_fop_write+0x161/0x440 fs/kernfs/file.c:330
__vfs_write+0xe4/0x630 fs/read_write.c:480
vfs_write+0x17f/0x4d0 fs/read_write.c:544
SYSC_write fs/read_write.c:590 [inline]
SyS_write+0xf2/0x210 fs/read_write.c:582
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb

The buggy address belongs to the object at ffff8880af2dd040
which belongs to the cache kmalloc-32 of size 32
The buggy address is located 24 bytes to the right of
32-byte region [ffff8880af2dd040, ffff8880af2dd060)
The buggy address belongs to the page:
page:ffffea0002bcb740 count:1 mapcount:0 mapping:ffff8880af2dd000 index:0xffff8880af2ddfc1
flags: 0xfff00000000100(slab)
raw: 00fff00000000100 ffff8880af2dd000 ffff8880af2ddfc1 0000000100000006
raw: ffffea0002ae6ce0 ffffea0002b06960 ffff88813fe741c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff8880af2dcf00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff8880af2dcf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880af2dd000: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
^
ffff8880af2dd080: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
ffff8880af2dd100: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
==================================================================


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