CVE-2024-26982: Squashfs: check the inode number is not the invalid value of zero
In the Linux kernel, the following vulnerability has been resolved:
Squashfs: check the inode number is not the invalid value of zero
Syskiller has produced an out of bounds access in fillmetaindex().
That out of bounds access is ultimately caused because the inode has an inode number with the invalid value of zero, which was not checked.
The reason this causes the out of bounds access is due to following sequence of events:
1. Fillmetaindex() is called to allocate (via emptymetaindex()) and fill a metadata index. It however suffers a data read error and aborts, invalidating the newly returned empty metadata index. It does this by setting the inode number of the index to zero, which means unused (zero is not a valid inode number).
2. When fillmetaindex() is subsequently called again on another read operation, locatemetaindex() returns the previous index because it matches the inode number of 0. Because this index has been returned it is expected to have been filled, and because it hasn't been, an out of bounds access is performed.
This patch adds a sanity check which checks that the inode number is not zero when the inode is created and returns -EINVAL if it is.
[phillip@squashfs.org.uk: whitespace fix]
Other sources
In the Linux kernel, the following vulnerability has been resolved:
Squashfs: check the inode number is not the invalid value of zero
The Linux kernel CVE team has assigned CVE-2024-26982 to this issue.
Upstream advisory: https://lore.kernel.org/linux-cve-announce/2024050141-CVE-2024-26982-8675@gregkh/T
— Red Hat
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2024-26982?
The severity level of CVE-2024-26982 is classified as high due to its potential for causing out of bounds access in the Linux kernel.
How do I fix CVE-2024-26982?
To fix CVE-2024-26982, update your kernel to the specified versions, such as Red Hat kernel 6.8.8 or 6.9, or Debian linux versions 6.12.12-1 or 6.12.15-1.
Which systems are affected by CVE-2024-26982?
CVE-2024-26982 affects certain versions of the Linux kernel, specifically those prior to the patched releases mentioned.
What does CVE-2024-26982 exploit?
CVE-2024-26982 exploits an out of bounds access in the fill_meta_index() function, which is triggered by an invalid inode number.
Is there a workaround for CVE-2024-26982?
There are no known workarounds for CVE-2024-26982; the only solution is to apply the necessary updates to the kernel.