cve/published/2024/CVE-2024-53690.mbox

From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: <linux-cve-announce@vger.kernel.org>
Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org>
Subject: CVE-2024-53690: nilfs2: prevent use of deleted inode

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

nilfs2: prevent use of deleted inode

syzbot reported a WARNING in nilfs_rmdir. [1]

Because the inode bitmap is corrupted, an inode with an inode number that
should exist as a ".nilfs" file was reassigned by nilfs_mkdir for "file0",
causing an inode duplication during execution.  And this causes an
underflow of i_nlink in rmdir operations.

The inode is used twice by the same task to unmount and remove directories
".nilfs" and "file0", it trigger warning in nilfs_rmdir.

Avoid to this issue, check i_nlink in nilfs_iget(), if it is 0, it means
that this inode has been deleted, and iput is executed to reclaim it.

[1]
WARNING: CPU: 1 PID: 5824 at fs/inode.c:407 drop_nlink+0xc4/0x110 fs/inode.c:407
...
Call Trace:
 <TASK>
 nilfs_rmdir+0x1b0/0x250 fs/nilfs2/namei.c:342
 vfs_rmdir+0x3a3/0x510 fs/namei.c:4394
 do_rmdir+0x3b5/0x580 fs/namei.c:4453
 __do_sys_rmdir fs/namei.c:4472 [inline]
 __se_sys_rmdir fs/namei.c:4470 [inline]
 __x64_sys_rmdir+0x47/0x50 fs/namei.c:4470
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The Linux kernel CVE team has assigned CVE-2024-53690 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 2.6.30 with commit d25006523d0b9e49fd097b2e974e7c8c05bd7f54 and fixed in 5.4.289 with commit 55e4baa0d32f0530ddc64c26620e1f2f8fa2724c
	Issue introduced in 2.6.30 with commit d25006523d0b9e49fd097b2e974e7c8c05bd7f54 and fixed in 5.10.233 with commit 5d4ed71327b0b5f3b179a19dc3c06be9509ab3db
	Issue introduced in 2.6.30 with commit d25006523d0b9e49fd097b2e974e7c8c05bd7f54 and fixed in 5.15.176 with commit 912188316a8c9e41b8c1603c2276a05043b14f96
	Issue introduced in 2.6.30 with commit d25006523d0b9e49fd097b2e974e7c8c05bd7f54 and fixed in 6.1.122 with commit ef942d233643777f7b2a5deef620e82942983143
	Issue introduced in 2.6.30 with commit d25006523d0b9e49fd097b2e974e7c8c05bd7f54 and fixed in 6.6.68 with commit 284760b320a0bac411b18108316939707dccb12b
	Issue introduced in 2.6.30 with commit d25006523d0b9e49fd097b2e974e7c8c05bd7f54 and fixed in 6.12.7 with commit ff561987ff12b6a3233431ff659b5d332e22f153
	Issue introduced in 2.6.30 with commit d25006523d0b9e49fd097b2e974e7c8c05bd7f54 and fixed in 6.13 with commit 901ce9705fbb9f330ff1f19600e5daf9770b0175

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-53690
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	fs/nilfs2/inode.c
	fs/nilfs2/namei.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/55e4baa0d32f0530ddc64c26620e1f2f8fa2724c
	https://git.kernel.org/stable/c/5d4ed71327b0b5f3b179a19dc3c06be9509ab3db
	https://git.kernel.org/stable/c/912188316a8c9e41b8c1603c2276a05043b14f96
	https://git.kernel.org/stable/c/ef942d233643777f7b2a5deef620e82942983143
	https://git.kernel.org/stable/c/284760b320a0bac411b18108316939707dccb12b
	https://git.kernel.org/stable/c/ff561987ff12b6a3233431ff659b5d332e22f153
	https://git.kernel.org/stable/c/901ce9705fbb9f330ff1f19600e5daf9770b0175