CVE-2024-49983

ext4: drop ppath from ext4_ext_replay_update_ex() to avoid double-free

Published Oct 21, 2024 CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed
Description
In the Linux kernel, the following vulnerability has been resolved:

ext4: drop ppath from ext4_ext_replay_update_ex() to avoid double-free

When calling ext4_force_split_extent_at() in ext4_ext_replay_update_ex(),
the 'ppath' is updated but it is the 'path' that is freed, thus potentially
triggering a double-free in the following process:

ext4_ext_replay_update_ex
ppath = path
ext4_force_split_extent_at(&ppath)
ext4_split_extent_at
ext4_ext_insert_extent
ext4_ext_create_new_leaf
ext4_ext_grow_indepth
ext4_find_extent
if (depth > path[0].p_maxdepth)
kfree(path) ---> path First freed
*orig_path = path = NULL ---> null ppath
kfree(path) ---> path double-free !!!

So drop the unnecessary ppath and use path directly to avoid this problem.
And use ext4_find_extent() directly to update path, avoiding unnecessary
memory allocation and freeing. Also, propagate the error returned by
ext4_find_extent() instead of using strange error codes.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-4008-1 linux-6.1 security update
Debian DLA Debian DLA DLA-4075-1 linux security update
Ubuntu USN Ubuntu USN USN-7166-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7166-2 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7166-3 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7166-4 Linux kernel (Xilinx ZynqMP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7186-1 Linux kernel (Intel IoTG) vulnerabilities
Ubuntu USN Ubuntu USN USN-7186-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7194-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7276-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7277-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7301-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7303-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7303-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7303-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7304-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7310-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7311-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7384-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7384-2 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7385-1 Linux kernel (IBM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7386-1 Linux kernel (OEM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7403-1 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7468-1 Linux kernel (Azure, N-Series) vulnerabilities
History
Type Values Removed Values Added
First Time appeared Redhat
Redhat enterprise Linux
CPEs cpe:/a:redhat:enterprise_linux:9
cpe:/o:redhat:enterprise_linux:9
Vendors & Products Redhat
Redhat enterprise Linux
Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Weaknesses CWE-415
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
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': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}

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

Type Values Removed Values Added
Metrics ssvc

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

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: ext4: drop ppath from ext4_ext_replay_update_ex() to avoid double-free When calling ext4_force_split_extent_at() in ext4_ext_replay_update_ex(), the 'ppath' is updated but it is the 'path' that is freed, thus potentially triggering a double-free in the following process: ext4_ext_replay_update_ex ppath = path ext4_force_split_extent_at(&ppath) ext4_split_extent_at ext4_ext_insert_extent ext4_ext_create_new_leaf ext4_ext_grow_indepth ext4_find_extent if (depth > path[0].p_maxdepth) kfree(path) ---> path First freed *orig_path = path = NULL ---> null ppath kfree(path) ---> path double-free !!! So drop the unnecessary ppath and use path directly to avoid this problem. And use ext4_find_extent() directly to update path, avoiding unnecessary memory allocation and freeing. Also, propagate the error returned by ext4_find_extent() instead of using strange error codes.
Title ext4: drop ppath from ext4_ext_replay_update_ex() to avoid double-free
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
Aug 5, 2026, 11:40 AM
Reserved
Oct 21, 2024, 12:17 PM
Status
Modified
Published
Oct 21, 2024, 6:15 PM
Modified
Aug 4, 2026, 11:21 AM
Severity
Moderate
Public date
Oct 21, 2024, 12:00 AM