REDHAT-BUG-2309273: Low severity red hat kernel-devel vulnerability
In the Linux kernel, the following vulnerability has been resolved:
fuse: Initialize beyond-EOF page contents before setting uptodate
fusenotifystore(), unlike fusedoreadpage(), does not enable page zeroing (because it can be used to change partial page contents).
So fusenotifystore() must be more careful to fully initialize page contents (including parts of the page that are beyond end-of-file) before marking the page uptodate.
The current code can leave beyond-EOF page contents uninitialized, which makes these uninitialized page contents visible to userspace via mmap().
This is an information leak, but only affects systems which do not enable init-on-alloc (via CONFIGINITONALLOCDEFAULTON=y or the corresponding kernel command line parameter).
Affected Software
Event History
Frequently Asked Questions
What is the severity of REDHAT-BUG-2309273?
The severity of REDHAT-BUG-2309273 is categorized as moderate in the context of the Linux kernel.
How do I fix REDHAT-BUG-2309273?
To fix REDHAT-BUG-2309273, apply the latest kernel update available from your Linux distribution.
What systems are affected by REDHAT-BUG-2309273?
REDHAT-BUG-2309273 affects versions of the Linux kernel that utilize fuse_notify_store functionality.
What does REDHAT-BUG-2309273 involve?
REDHAT-BUG-2309273 involves an issue with the Linux kernel's handling of page initialization beyond the end of file.
Is there a workaround for REDHAT-BUG-2309273?
Currently, the recommended approach is to update the kernel, as no specific workaround for REDHAT-BUG-2309273 is provided.