[v6.1] KASAN: use-after-free Read in search_by_entry_key

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f17b0ab65d17 Linux 6.1.25
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=17dcf757c80000
kernel config: https://syzkaller.appspot.com/x/.config?x=73f7ee8e484b74b7
dashboard link: https://syzkaller.appspot.com/bug?extid=f1695d226551f134846a
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/553994c02131/disk-f17b0ab6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/c88e4d2795a5/vmlinux-f17b0ab6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d788d429a3a9/Image-f17b0ab6.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f1695d...@syzkaller.appspotmail.com

REISERFS (device loop1): Using r5 hash to sort names
==================================================================
BUG: KASAN: use-after-free in bin_search_in_dir_item fs/reiserfs/namei.c:40 [inline]
BUG: KASAN: use-after-free in search_by_entry_key+0x45c/0xe88 fs/reiserfs/namei.c:165
Read of size 4 at addr ffff000134ba5fc4 by task syz-executor.1/7035

CPU: 0 PID: 7035 Comm: syz-executor.1 Not tainted 6.1.25-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
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:284 [inline]
print_report+0x174/0x4c0 mm/kasan/report.c:395
kasan_report+0xd4/0x130 mm/kasan/report.c:495
__asan_report_load_n_noabort+0x28/0x34 mm/kasan/report_generic.c:361
bin_search_in_dir_item fs/reiserfs/namei.c:40 [inline]
search_by_entry_key+0x45c/0xe88 fs/reiserfs/namei.c:165
reiserfs_find_entry+0x288/0x149c fs/reiserfs/namei.c:322
reiserfs_lookup+0x184/0x3c4 fs/reiserfs/namei.c:368
__lookup_slow+0x250/0x374 fs/namei.c:1685
lookup_one_len+0x178/0x28c fs/namei.c:2711
reiserfs_lookup_privroot+0x8c/0x204 fs/reiserfs/xattr.c:973
reiserfs_fill_super+0x1bc0/0x2028 fs/reiserfs/super.c:2174
mount_bdev+0x26c/0x368 fs/super.c:1423
get_super_block+0x44/0x58 fs/reiserfs/super.c:2601
legacy_get_tree+0xd4/0x16c fs/fs_context.c:610
vfs_get_tree+0x90/0x274 fs/super.c:1553
do_new_mount+0x25c/0x8c8 fs/namespace.c:3040
path_mount+0x590/0xe58 fs/namespace.c:3370
do_mount fs/namespace.c:3383 [inline]
__do_sys_mount fs/namespace.c:3591 [inline]
__se_sys_mount fs/namespace.c:3568 [inline]
__arm64_sys_mount+0x45c/0x594 fs/namespace.c:3568
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
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:581

The buggy address belongs to the physical page:
page:000000007b990b99 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x174ba5
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0004d2e988 fffffc0004d2e908 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff000134ba5e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff000134ba5f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff000134ba5f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff000134ba6000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff000134ba6080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
REISERFS (device loop1): Created .reiserfs_priv - reserved for xattr storage.


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: ca48fc16c493 Linux 6.1.27
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=12758dbc280000
kernel config: https://syzkaller.appspot.com/x/.config?x=aea4bb7802570997

dashboard link: https://syzkaller.appspot.com/bug?extid=f1695d226551f134846a
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16273bea280000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1322de42280000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ec11c1903c52/disk-ca48fc16.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8ce41c1ad391/vmlinux-ca48fc16.xz
kernel image: https://storage.googleapis.com/syzbot-assets/affba5631cad/Image-ca48fc16.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/afba74c80fc2/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f1695d...@syzkaller.appspotmail.com

REISERFS (device loop0): journal params: device loop0, size 512, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30
REISERFS (device loop0): checking transaction log (loop0)
REISERFS (device loop0): Using r5 hash to sort names

==================================================================
BUG: KASAN: use-after-free in bin_search_in_dir_item fs/reiserfs/namei.c:40 [inline]
BUG: KASAN: use-after-free in search_by_entry_key+0x45c/0xe88 fs/reiserfs/namei.c:165

Read of size 4 at addr ffff0000e0e74004 by task syz-executor275/4216

CPU: 0 PID: 4216 Comm: syz-executor275 Not tainted 6.1.27-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023

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:284 [inline]
print_report+0x174/0x4c0 mm/kasan/report.c:395
kasan_report+0xd4/0x130 mm/kasan/report.c:495
__asan_report_load_n_noabort+0x28/0x34 mm/kasan/report_generic.c:361
bin_search_in_dir_item fs/reiserfs/namei.c:40 [inline]
search_by_entry_key+0x45c/0xe88 fs/reiserfs/namei.c:165

reiserfs_find_entry+0xd20/0x149c fs/reiserfs/namei.c:322

reiserfs_lookup+0x184/0x3c4 fs/reiserfs/namei.c:368
__lookup_slow+0x250/0x374 fs/namei.c:1685
lookup_one_len+0x178/0x28c fs/namei.c:2711
reiserfs_lookup_privroot+0x8c/0x204 fs/reiserfs/xattr.c:973

reiserfs_fill_super+0x15b4/0x2028 fs/reiserfs/super.c:2192

mount_bdev+0x26c/0x368 fs/super.c:1423
get_super_block+0x44/0x58 fs/reiserfs/super.c:2601
legacy_get_tree+0xd4/0x16c fs/fs_context.c:610
vfs_get_tree+0x90/0x274 fs/super.c:1553
do_new_mount+0x25c/0x8c8 fs/namespace.c:3040
path_mount+0x590/0xe58 fs/namespace.c:3370
do_mount fs/namespace.c:3383 [inline]
__do_sys_mount fs/namespace.c:3591 [inline]
__se_sys_mount fs/namespace.c:3568 [inline]
__arm64_sys_mount+0x45c/0x594 fs/namespace.c:3568
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
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:581

The buggy address belongs to the physical page:

page:00000000d4852bc2 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x120e74
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0003839d48 ffff0001b45cc220 0000000000000000

raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:

ffff0000e0e73f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff0000e0e73f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff0000e0e74000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff0000e0e74080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff0000e0e74100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================


---
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