In the Linux kernel, the following vulnerability has been resolved:
cachefiles: flush all requests after setting CACHEFILES_DEAD
In ondemand mode, when the daemon is processing an open request, if the
kernel flags the cache as CACHEFILES_DEAD, the cachefiles_daemon_write()
will always return -EIO, so the daemon can’t pass the copen to the kernel.
Then the kernel process that is waiting for the copen triggers a hung_task.
Since the DEAD state is irreversible, it can only be exited by closing
/dev/cachefiles. Therefore, after calling cachefiles_io_error() to mark
the cache as CACHEFILES_DEAD, if in ondemand mode, flush all requests to
avoid the above hungtask. We may still be able to read some of the cached
data before closing the fd of /dev/cachefiles.
Note that this relies on the patch that adds reference counting to the req,
otherwise it may UAF.
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
ubuntu | 24.04 | noarch | linux | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-aws | < any | UNKNOWN |
ubuntu | 22.04 | noarch | linux-aws-6.5 | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-azure | < any | UNKNOWN |
ubuntu | 22.04 | noarch | linux-azure-6.5 | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-gcp | < any | UNKNOWN |
ubuntu | 22.04 | noarch | linux-gcp-6.5 | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-gke | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-ibm | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-intel | < any | UNKNOWN |
git.kernel.org/linus/85e833cd7243bda7285492b0653c3abb1e2e757b (6.10-rc4)
git.kernel.org/stable/c/320ba9cbca78be79c912143bbba1d1b35ca55cf0
git.kernel.org/stable/c/3bf0b8030296e9ee60d3d4c15849ad9ac0b47081
git.kernel.org/stable/c/85e833cd7243bda7285492b0653c3abb1e2e757b
git.kernel.org/stable/c/e73fac95084839c5178d97e81c6a2051251bdc00
launchpad.net/bugs/cve/CVE-2024-40935
nvd.nist.gov/vuln/detail/CVE-2024-40935
security-tracker.debian.org/tracker/CVE-2024-40935
www.cve.org/CVERecord?id=CVE-2024-40935