CVE-2024-49884: ext4: fix slab-use-after-free in ext4_split_extent_at()
ext4: fix slab-use-after-free in ext4splitextentat()
Other sources
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— Launchpad
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 5.10.234-1Fixed in 6.1.129-1Fixed in 6.1.135-1Fixed in 6.12.25-1Fixed in 6.12.27-1 - Upgrade
Upgrade
debian/linux-6.1to a version that resolves this vulnerability.Fixed in 6.1.129-1~deb11u1 - Configuration
Apply the ext4 fix described in the provided text: adjust ext4 code so that when EXT_DEBUG is defined, avoid passing a potentially freed `path` pointer into `ext4_ext_show_leaf()`. Specifically, use `*ppath` directly as the `ext4_ext_show_leaf()` input to avoid use-after-free and unnecessary path updates.
Linux kernel ext4 avoid possible use-after-free when EXT_DEBUG is defined by not using ext4_ext_show_leaf() with a freed path pointer = Use *ppath directly as the ext4_ext_show_leaf() input when EXT_DEBUG is defined (avoid *path use) - Configuration
Apply the ext4 logic change described in the provided text: when zeroing out or fixing extent length, call `ext4_find_extent()` to update the extent path (instead of continuing with a stale pointer that can lead to slab use-after-free).
Linux kernel ext4 extent zeroout/fix flow = Call ext4_find_extent() to update the path when fixing extent length
Event History
Frequently Asked Questions
What is the severity of CVE-2024-49884?
CVE-2024-49884 is classified as a high-severity vulnerability in the Linux kernel due to a use-after-free issue.
How do I fix CVE-2024-49884?
To fix CVE-2024-49884, update your Linux kernel to a version that includes the patch, such as 6.1.123-1 or 6.12.11-1.
Which versions of the Linux kernel are affected by CVE-2024-49884?
CVE-2024-49884 affects Linux kernel versions between 3.18 and 5.10.227, as well as various versions up to 6.11.3.
Is CVE-2024-49884 exploitable?
Yes, CVE-2024-49884 can be potentially exploited by attackers to corrupt memory, leading to privilege escalation or denial of service.
What does the term 'use-after-free' mean in the context of CVE-2024-49884?
In the context of CVE-2024-49884, 'use-after-free' refers to accessing memory after it has been freed, which can lead to unstable system behavior or security vulnerabilities.