[v6.1] KASAN: slab-out-of-bounds Read in dtInsertEntry

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3dfebb87d7eb Linux 6.1.133
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1307ba74580000
kernel config: https://syzkaller.appspot.com/x/.config?x=98f87318ae7e5ebb
dashboard link: https://syzkaller.appspot.com/bug?extid=45b09b7bfabcb2112ea2
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d6040a992ff7/disk-3dfebb87.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7d99423d8a71/vmlinux-3dfebb87.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2098792ab6b2/bzImage-3dfebb87.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+45b09b...@syzkaller.appspotmail.com

read_mapping_page failed!
ERROR: (device loop2): txCommit:
==================================================================
BUG: KASAN: slab-out-of-bounds in dtInsertEntry+0x10d6/0x1770 fs/jfs/jfs_dtree.c:3752
Read of size 4 at addr ffff888056e2404c by task syz.2.90/4791

CPU: 1 PID: 4791 Comm: syz.2.90 Not tainted 6.1.133-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
print_address_description mm/kasan/report.c:316 [inline]
print_report+0x15f/0x4f0 mm/kasan/report.c:427
kasan_report+0x136/0x160 mm/kasan/report.c:531
dtInsertEntry+0x10d6/0x1770 fs/jfs/jfs_dtree.c:3752
dtSplitPage+0x2d8f/0x3ec0 fs/jfs/jfs_dtree.c:1595
dtSplitUp fs/jfs/jfs_dtree.c:1091 [inline]
dtInsert+0x14bc/0x6c80 fs/jfs/jfs_dtree.c:870
jfs_create+0x7b2/0xbb0 fs/jfs/namei.c:137
lookup_open fs/namei.c:3482 [inline]
open_last_lookups fs/namei.c:3550 [inline]
path_openat+0x12f1/0x2e60 fs/namei.c:3780
do_filp_open+0x230/0x480 fs/namei.c:3810
do_sys_openat2+0x13b/0x4f0 fs/open.c:1318
do_sys_open fs/open.c:1334 [inline]
__do_sys_open fs/open.c:1342 [inline]
__se_sys_open fs/open.c:1338 [inline]
__x64_sys_open+0x221/0x270 fs/open.c:1338
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9cab58d169
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9cac3ba038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f9cab7a5fa0 RCX: 00007f9cab58d169
RDX: 0000000000000023 RSI: 0000000000064842 RDI: 0000200000000080
RBP: 00007f9cab60e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f9cab7a5fa0 R15: 00007fff781508b8
</TASK>

Allocated by task 4791:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
__kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
slab_alloc_node mm/slub.c:3398 [inline]
slab_alloc mm/slub.c:3406 [inline]
__kmem_cache_alloc_lru mm/slub.c:3413 [inline]
kmem_cache_alloc_lru+0x10c/0x2d0 mm/slub.c:3429
alloc_inode_sb include/linux/fs.h:3245 [inline]
jfs_alloc_inode+0x24/0x60 fs/jfs/super.c:105
alloc_inode fs/inode.c:261 [inline]
iget_locked+0x1c8/0x830 fs/inode.c:1373
jfs_iget+0x1e/0x3b0 fs/jfs/inode.c:29
jfs_lookup+0x222/0x400 fs/jfs/namei.c:1467
__lookup_slow+0x27e/0x3d0 fs/namei.c:1690
lookup_slow+0x53/0x70 fs/namei.c:1707
walk_component fs/namei.c:1998 [inline]
link_path_walk+0x9d6/0xee0 fs/namei.c:2325
path_parentat fs/namei.c:2526 [inline]
__filename_parentat+0x25e/0x6e0 fs/namei.c:2550
filename_parentat fs/namei.c:2568 [inline]
do_renameat2+0x39b/0x1440 fs/namei.c:4943
__do_sys_renameat2 fs/namei.c:5060 [inline]
__se_sys_renameat2 fs/namei.c:5057 [inline]
__x64_sys_renameat2+0xce/0xe0 fs/namei.c:5057
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff888056e23780
which belongs to the cache jfs_ip of size 2240
The buggy address is located 12 bytes to the right of
2240-byte region [ffff888056e23780, ffff888056e24040)

The buggy address belongs to the physical page:
page:ffffea00015b8800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x56e20
head:ffffea00015b8800 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888076d42201
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff88801af8b500
raw: 0000000000000000 00000000800d000d 00000001ffffffff ffff888076d42201
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 4791, tgid 4790 (syz.2.90), ts 120062058612, free_ts 108004892238
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2532
prep_new_page mm/page_alloc.c:2539 [inline]
get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4328
__alloc_pages+0x28d/0x770 mm/page_alloc.c:5606
alloc_slab_page+0x6a/0x150 mm/slub.c:1794
allocate_slab mm/slub.c:1939 [inline]
new_slab+0x84/0x2d0 mm/slub.c:1992
___slab_alloc+0xc20/0x1270 mm/slub.c:3180
__slab_alloc mm/slub.c:3279 [inline]
slab_alloc_node mm/slub.c:3364 [inline]
slab_alloc mm/slub.c:3406 [inline]
__kmem_cache_alloc_lru mm/slub.c:3413 [inline]
kmem_cache_alloc_lru+0x1a5/0x2d0 mm/slub.c:3429
alloc_inode_sb include/linux/fs.h:3245 [inline]
jfs_alloc_inode+0x24/0x60 fs/jfs/super.c:105
alloc_inode fs/inode.c:261 [inline]
new_inode_pseudo+0x61/0x1d0 fs/inode.c:1063
new_inode+0x25/0x1d0 fs/inode.c:1091
jfs_fill_super+0x404/0xc40 fs/jfs/super.c:544
mount_bdev+0x2c9/0x3f0 fs/super.c:1443
legacy_get_tree+0xeb/0x180 fs/fs_context.c:632
vfs_get_tree+0x88/0x270 fs/super.c:1573
do_new_mount+0x2ba/0xb40 fs/namespace.c:3056
do_mount fs/namespace.c:3399 [inline]
__do_sys_mount fs/namespace.c:3607 [inline]
__se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3584
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1459 [inline]
free_pcp_prepare mm/page_alloc.c:1509 [inline]
free_unref_page_prepare+0x12a6/0x15b0 mm/page_alloc.c:3384
free_unref_page+0x33/0x3e0 mm/page_alloc.c:3479
free_slab mm/slub.c:2031 [inline]
discard_slab mm/slub.c:2037 [inline]
__unfreeze_partials+0x1b7/0x210 mm/slub.c:2586
put_cpu_partial+0x17b/0x250 mm/slub.c:2662
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
slab_alloc_node mm/slub.c:3398 [inline]
kmem_cache_alloc_node+0x136/0x310 mm/slub.c:3443
__alloc_skb+0xd3/0x2c0 net/core/skbuff.c:505
alloc_skb include/linux/skbuff.h:1271 [inline]
alloc_skb_with_frags+0xa4/0x740 net/core/skbuff.c:6162
sock_alloc_send_pskb+0x915/0xa50 net/core/sock.c:2750
unix_dgram_sendmsg+0x5b1/0x2060 net/unix/af_unix.c:1918
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
__sys_sendto+0x480/0x600 net/socket.c:2153
__do_sys_sendto net/socket.c:2165 [inline]
__se_sys_sendto net/socket.c:2161 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2161
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81

Memory state around the buggy address:
ffff888056e23f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff888056e23f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888056e24000: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
^
ffff888056e24080: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
ffff888056e24100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 420102835862 Linux 6.1.134
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16957398580000
kernel config: https://syzkaller.appspot.com/x/.config?x=8378dd042adba5b4

dashboard link: https://syzkaller.appspot.com/bug?extid=45b09b7bfabcb2112ea2
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11957398580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1230cfe4580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a5ee15572a4a/disk-42010283.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/728dbc1d7c01/vmlinux-42010283.xz
kernel image: https://storage.googleapis.com/syzbot-assets/319d47731f5b/Image-42010283.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/f68ae3078b2d/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=10b320cc580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+45b09b...@syzkaller.appspotmail.com

ERROR: (device loop0): txAbort:
read_mapping_page failed!
ERROR: (device loop0): txAbort:
==================================================================
BUG: KASAN: slab-out-of-bounds in dtInsertEntry+0xc78/0x1170 fs/jfs/jfs_dtree.c:3753
Read of size 4 at addr ffff0000e1e5c04c by task syz-executor350/4291

CPU: 1 PID: 4291 Comm: syz-executor350 Not tainted 6.1.134-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025

Call trace:
dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:316 [inline]
print_report+0x174/0x4c0 mm/kasan/report.c:427
kasan_report+0xd4/0x130 mm/kasan/report.c:531
__asan_report_load4_noabort+0x2c/0x38 mm/kasan/report_generic.c:350
dtInsertEntry+0xc78/0x1170 fs/jfs/jfs_dtree.c:3753
dtSplitPage+0x22c8/0x3088 fs/jfs/jfs_dtree.c:1596
dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline]
dtInsert+0x110c/0x57a4 fs/jfs/jfs_dtree.c:871
jfs_create+0x698/0xa1c fs/jfs/namei.c:137
vfs_create+0x2cc/0x434 fs/namei.c:3184
do_mknodat+0x390/0x610 fs/namei.c:4035
__do_sys_mknodat fs/namei.c:4063 [inline]
__se_sys_mknodat fs/namei.c:4060 [inline]
__arm64_sys_mknodat+0xb0/0xcc fs/namei.c:4060
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Allocated by task 4291:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4c/0x80 mm/kasan/common.c:52
kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505
__kasan_slab_alloc+0x74/0x8c mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x74/0x458 mm/slab.h:737

slab_alloc_node mm/slub.c:3398 [inline]
slab_alloc mm/slub.c:3406 [inline]
__kmem_cache_alloc_lru mm/slub.c:3413 [inline]

kmem_cache_alloc_lru+0x1ac/0x2f8 mm/slub.c:3429
alloc_inode_sb include/linux/fs.h:3245 [inline]
jfs_alloc_inode+0x2c/0x68 fs/jfs/super.c:105
alloc_inode fs/inode.c:261 [inline]
iget_locked+0x170/0x708 fs/inode.c:1373
jfs_iget+0x30/0x364 fs/jfs/inode.c:29
jfs_lookup+0x1e8/0x39c fs/jfs/namei.c:1467
__lookup_slow+0x250/0x374 fs/namei.c:1690
lookup_slow+0x60/0x84 fs/namei.c:1707
walk_component fs/namei.c:1998 [inline]
link_path_walk+0x830/0xcc8 fs/namei.c:2325
path_parentat fs/namei.c:2526 [inline]
__filename_parentat+0x1e4/0x5d0 fs/namei.c:2550
filename_parentat fs/namei.c:2568 [inline]
do_renameat2+0x2f4/0xe64 fs/namei.c:4943

__do_sys_renameat2 fs/namei.c:5060 [inline]
__se_sys_renameat2 fs/namei.c:5057 [inline]

__arm64_sys_renameat2+0xe0/0xfc fs/namei.c:5057
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the object at ffff0000e1e5b780

which belongs to the cache jfs_ip of size 2240
The buggy address is located 12 bytes to the right of

2240-byte region [ffff0000e1e5b780, ffff0000e1e5c040)

The buggy address belongs to the physical page:

page:000000006b35f598 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x121e58
head:000000006b35f598 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000010200 0000000000000000 dead000000000122 ffff0000c6f9a300
raw: 0000000000000000 00000000800d000d 00000001ffffffff 0000000000000000

page dumped because: kasan: bad access detected

Memory state around the buggy address:

ffff0000e1e5bf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff0000e1e5bf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff0000e1e5c000: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
^
ffff0000e1e5c080: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
ffff0000e1e5c100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
find_entry called with index >= next_index
read_mapping_page failed!
ERROR: (device loop0): txAbort:



---
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