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Date: Tue, 16 Apr 2024 06:14:20 -0700
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Subject: [syzbot] [btrfs?] KMSAN: kernel-infoleak in btrfs_ioctl_logical_to_ino
 (2)
From: syzbot <syzbot+510a1abbb8116eeb341d@syzkaller.appspotmail.com>
To: clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, 
	linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, 
	linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com
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Hello,

syzbot found the following issue on:

HEAD commit:    cef27048e5c2 Merge tag 'bcachefs-2024-04-15' of https://ev..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11a1fec7180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=87a805e655619c64
dashboard link: https://syzkaller.appspot.com/bug?extid=510a1abbb8116eeb341d
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/fce0439cf562/disk-cef27048.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/99540e71cf72/vmlinux-cef27048.xz
kernel image: https://storage.googleapis.com/syzbot-assets/65fbfc2c486f/bzImage-cef27048.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+510a1abbb8116eeb341d@syzkaller.appspotmail.com

BTRFS info (device loop1): first mount of filesystem c9fe44da-de57-406a-8241-57ec7d4412cf
BTRFS info (device loop1): using crc32c (crc32c-generic) checksum algorithm
BTRFS info (device loop1): using free-space-tree
=====================================================
BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_user+0xbc/0x110 lib/usercopy.c:40
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 _copy_to_user+0xbc/0x110 lib/usercopy.c:40
 copy_to_user include/linux/uaccess.h:191 [inline]
 btrfs_ioctl_logical_to_ino+0x440/0x750 fs/btrfs/ioctl.c:3499
 btrfs_ioctl+0x714/0x1260
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl+0x261/0x450 fs/ioctl.c:890
 __x64_sys_ioctl+0x96/0xe0 fs/ioctl.c:890
 x64_sys_call+0x1883/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 __kmalloc_large_node+0x231/0x370 mm/slub.c:3921
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc_node+0xb07/0x1060 mm/slub.c:3973
 kmalloc_node include/linux/slab.h:648 [inline]
 kvmalloc_node+0xc0/0x2d0 mm/util.c:634
 kvmalloc include/linux/slab.h:766 [inline]
 init_data_container+0x49/0x1e0 fs/btrfs/backref.c:2779
 btrfs_ioctl_logical_to_ino+0x17c/0x750 fs/btrfs/ioctl.c:3480
 btrfs_ioctl+0x714/0x1260
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl+0x261/0x450 fs/ioctl.c:890
 __x64_sys_ioctl+0x96/0xe0 fs/ioctl.c:890
 x64_sys_call+0x1883/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Bytes 40-65535 of 65536 are uninitialized
Memory access of size 65536 starts at ffff888045a40000

CPU: 0 PID: 5428 Comm: syz-executor.1 Not tainted 6.9.0-rc4-syzkaller-00028-gcef27048e5c2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
=====================================================


---
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