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

btrfs: qgroup: do not warn on record without old_roots populated

[BUG]
There are some reports from the mailing list that since v6.1 kernel, the
WARN_ON() inside btrfs_qgroup_account_extent() gets triggered during
rescan:

WARNING: CPU: 3 PID: 6424 at fs/btrfs/qgroup.c:2756 btrfs_qgroup_account_extents+0x1ae/0x260 [btrfs]
CPU: 3 PID: 6424 Comm: snapperd Tainted: P OE 6.1.2-1-default #1 openSUSE Tumbleweed 05c7a1b1b61d5627475528f71f50444637b5aad7
RIP: 0010:btrfs_qgroup_account_extents+0x1ae/0x260 [btrfs]
Call Trace:
<TASK>
btrfs_commit_transaction+0x30c/0xb40 [btrfs c39c9c546c241c593f03bd6d5f39ea1b676250f6]
? start_transaction+0xc3/0x5b0 [btrfs c39c9c546c241c593f03bd6d5f39ea1b676250f6]
btrfs_qgroup_rescan+0x42/0xc0 [btrfs c39c9c546c241c593f03bd6d5f39ea1b676250f6]
btrfs_ioctl+0x1ab9/0x25c0 [btrfs c39c9c546c241c593f03bd6d5f39ea1b676250f6]
? __rseq_handle_notify_resume+0xa9/0x4a0
? mntput_no_expire+0x4a/0x240
? __seccomp_filter+0x319/0x4d0
__x64_sys_ioctl+0x90/0xd0
do_syscall_64+0x5b/0x80
? syscall_exit_to_user_mode+0x17/0x40
? do_syscall_64+0x67/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fd9b790d9bf
</TASK>

[CAUSE]
Since commit e15e9f43c7ca ("btrfs: introduce
BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING to skip qgroup accounting"), if
our qgroup is already in inconsistent state, we will no longer do the
time-consuming backref walk.

This can leave some qgroup records without a valid old_roots ulist.
Normally this is fine, as btrfs_qgroup_account_extents() would also skip
those records if we have NO_ACCOUNTING flag set.

But there is a small window, if we have NO_ACCOUNTING flag set, and
inserted some qgroup_record without a old_roots ulist, but then the user
triggered a qgroup rescan.

During btrfs_qgroup_rescan(), we firstly clear NO_ACCOUNTING flag, then
commit current transaction.

And since we have a qgroup_record with old_roots = NULL, we trigger the
WARN_ON() during btrfs_qgroup_account_extents().

[FIX]
Unfortunately due to the introduction of NO_ACCOUNTING flag, the
assumption that every qgroup_record would have its old_roots populated
is no longer correct.

Fix the false alerts and drop the WARN_ON().

No CVSS v4.0

Attack Vector Local

Attack Complexity High

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00018.

Exploitation none

Automatable no

Technical Impact partial

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
Linux Linux unaffected
Version Status Constraints
e15e9f43c7ca25603fcf4c20d44ec777726f1034 affected < bb2c2e62539f2b63c5e0beb51501d328260c7595
e15e9f43c7ca25603fcf4c20d44ec777726f1034 affected < 75181406b4eafacc531ff2ee5fb032bd93317e2b
Linux Linux affected
Version Status Constraints
6.1 affected —
0 unaffected < 6.1
6.1.8 unaffected ≤ 6.1.*
6.2 unaffected ≤ *

Configuration 1 [-]

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.2:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.2:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.2:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.2:rc4:*:*:*:*:*:*

No data.

No data.

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Advisories

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Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://git.kernel.org/stable/c/75181406b4eafacc531ff2ee5fb032bd93317e2b cve-icon cve-icon
https://git.kernel.org/stable/c/bb2c2e62539f2b63c5e0beb51501d328260c7595 cve-icon cve-icon
https://lore.kernel.org/linux-cve-announce/2024082112-CVE-2023-52897-e4ef@gregkh/T cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2023-52897 cve-icon
https://www.cve.org/CVERecord?id=CVE-2023-52897 cve-icon
History

Thu, 26 Sep 2024 10:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-399

Fri, 13 Sep 2024 14:15:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Weaknesses NVD-CWE-noinfo
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.2:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.2:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.2:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.2:rc4:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

 cvssV3_1

{'score': 4.7, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'}

Wed, 11 Sep 2024 13:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Wed, 21 Aug 2024 21:30:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

 cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate

Wed, 21 Aug 2024 06:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: btrfs: qgroup: do not warn on record without old_roots populated [BUG] There are some reports from the mailing list that since v6.1 kernel, the WARN_ON() inside btrfs_qgroup_account_extent() gets triggered during rescan: WARNING: CPU: 3 PID: 6424 at fs/btrfs/qgroup.c:2756 btrfs_qgroup_account_extents+0x1ae/0x260 [btrfs] CPU: 3 PID: 6424 Comm: snapperd Tainted: P OE 6.1.2-1-default #1 openSUSE Tumbleweed 05c7a1b1b61d5627475528f71f50444637b5aad7 RIP: 0010:btrfs_qgroup_account_extents+0x1ae/0x260 [btrfs] Call Trace: <TASK> btrfs_commit_transaction+0x30c/0xb40 [btrfs c39c9c546c241c593f03bd6d5f39ea1b676250f6] ? start_transaction+0xc3/0x5b0 [btrfs c39c9c546c241c593f03bd6d5f39ea1b676250f6] btrfs_qgroup_rescan+0x42/0xc0 [btrfs c39c9c546c241c593f03bd6d5f39ea1b676250f6] btrfs_ioctl+0x1ab9/0x25c0 [btrfs c39c9c546c241c593f03bd6d5f39ea1b676250f6] ? __rseq_handle_notify_resume+0xa9/0x4a0 ? mntput_no_expire+0x4a/0x240 ? __seccomp_filter+0x319/0x4d0 __x64_sys_ioctl+0x90/0xd0 do_syscall_64+0x5b/0x80 ? syscall_exit_to_user_mode+0x17/0x40 ? do_syscall_64+0x67/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fd9b790d9bf </TASK> [CAUSE] Since commit e15e9f43c7ca ("btrfs: introduce BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING to skip qgroup accounting"), if our qgroup is already in inconsistent state, we will no longer do the time-consuming backref walk. This can leave some qgroup records without a valid old_roots ulist. Normally this is fine, as btrfs_qgroup_account_extents() would also skip those records if we have NO_ACCOUNTING flag set. But there is a small window, if we have NO_ACCOUNTING flag set, and inserted some qgroup_record without a old_roots ulist, but then the user triggered a qgroup rescan. During btrfs_qgroup_rescan(), we firstly clear NO_ACCOUNTING flag, then commit current transaction. And since we have a qgroup_record with old_roots = NULL, we trigger the WARN_ON() during btrfs_qgroup_account_extents(). [FIX] Unfortunately due to the introduction of NO_ACCOUNTING flag, the assumption that every qgroup_record would have its old_roots populated is no longer correct. Fix the false alerts and drop the WARN_ON().
Title btrfs: qgroup: do not warn on record without old_roots populated
References

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-05-04T07:45:30.484Z

Reserved: 2024-08-21T06:07:11.014Z

Link: CVE-2023-52897

cve-icon Vulnrichment

Updated: 2024-09-11T12:42:17.519Z

cve-icon NVD

Status : Analyzed

Published: 2024-08-21T07:15:06.120

Modified: 2024-09-13T13:52:07.717

Link: CVE-2023-52897

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-08-21T00:00:00Z

Links: CVE-2023-52897 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses