Re: [syzbot] [reiserfs?] KASAN: slab-out-of-bounds Read in search_by_key (2)

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    861deac3b092 Linux 6.7-rc7
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=121f1609e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e0c7078a6b901aa3
dashboard link: https://syzkaller.appspot.com/bug?extid=b3b14fb9f8a14c5d0267
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=10557e81e80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14206fd6e80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0ea60ee8ed32/disk-861deac3.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6d69fdc33021/vmlinux-861deac3.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f0158750d452/bzImage-861deac3.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/445a7c3f980d/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b3b14fb9f8a14c5d0267@xxxxxxxxxxxxxxxxxxxxxxxxx

REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.
=====================================================
BUG: KMSAN: uninit-value in comp_keys fs/reiserfs/stree.c:83 [inline]
BUG: KMSAN: uninit-value in bin_search fs/reiserfs/stree.c:173 [inline]
BUG: KMSAN: uninit-value in search_by_key+0x3293/0x6780 fs/reiserfs/stree.c:770
 comp_keys fs/reiserfs/stree.c:83 [inline]
 bin_search fs/reiserfs/stree.c:173 [inline]
 search_by_key+0x3293/0x6780 fs/reiserfs/stree.c:770
 reiserfs_delete_solid_item+0x4ec/0xe90 fs/reiserfs/stree.c:1419
 remove_save_link+0x2ed/0x420 fs/reiserfs/super.c:540
 reiserfs_truncate_file+0xd00/0x1b70 fs/reiserfs/inode.c:2314
 reiserfs_setattr+0x1b79/0x1ee0 fs/reiserfs/inode.c:3388
 notify_change+0x19fd/0x1af0 fs/attr.c:499
 do_truncate+0x22a/0x2a0 fs/open.c:66
 do_sys_ftruncate+0x81c/0xb30 fs/open.c:194
 __do_sys_ftruncate fs/open.c:205 [inline]
 __se_sys_ftruncate fs/open.c:203 [inline]
 __x64_sys_ftruncate+0x71/0xa0 fs/open.c:203
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Local variable cpu_key created at:
 reiserfs_delete_solid_item+0xbf/0xe90 fs/reiserfs/stree.c:1410
 remove_save_link+0x2ed/0x420 fs/reiserfs/super.c:540

CPU: 0 PID: 5006 Comm: syz-executor429 Not tainted 6.7.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
=====================================================


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#syz test: git://repo/address.git branch-or-commit-hash
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