In the Linux kernel, a previously undiscovered vulnerability (CVE-2024-46861) has been addressed, which could have led to the seizing up of the driver under certain circumstances. This vulnerability is related to the usbnet driver's ipheth and how it handles failing RX callbacks.
Insufficient memory
Failing RX callbacks could cause the driver to seize up, resulting in unstable performance or even system crashes.
Thanks to the recent patch, the vulnerability has been fixed by making these failure scenarios non-critical and allowing the driver to continue processing further incoming URBs.
Before the patch was applied, the code that handles the RX callbacks was as follows
if (ipheth_rx_fixup(skb)) {
if (urb->actual_length > )
netdev_err(dev->net, "ipheth_rx_fixup() failed\n");
goto exit;
}
After the fix, the code snippet for the RX callback handling now looks like this
if (ipheth_rx_fixup(skb)) {
if (urb->actual_length > )
netdev_warn(dev->net, "ipheth_rx_fixup() failed\n");
goto exit;
}
The main difference is that the netdev_err function has been replaced with a netdev_warn function. By doing so, the failures are now treated as non-critical, and the driver can continue processing further incoming URBs.
You can find the original patch addressing this vulnerability at the following link
- Linux kernel patch for the IPHeth RX Callback Vulnerability
The CVE-2024-46861 is still not published on the official databases, but as the Linux kernel patches continue to be developed and released, this vulnerability should be recognized and recorded soon.
Exploit Details
Since this vulnerability has been resolved before being exploited maliciously, there are no known exploit examples available. However, it is essential to update your systems to the latest patched kernel versions to ensure the highest level of security and remain protected from potential future attacks.
If potential attackers had developed an exploit for this vulnerability, it could have been used to force the driver to seize up by sending payloads specifically designed to trigger one of the failure scenarios:
Initiating a Denial of Service (DoS) attack by exhausting system memory to cause RX callback failure
It is essential to identify and patch vulnerabilities as early as possible to prevent such exploits from becoming reality.
Conclusion
The Linux kernel developers have resolved a significant vulnerability (CVE-2024-46861) related to the handling of failing RX callbacks in the usbnet driver's ipheth. This vulnerability could have led to driver seizing, causing performance issues or even system crashes.
To protect your systems, it is crucial to update to the latest kernel version and keep an eye on any newly discovered vulnerabilities. By staying up to date, you can help ensure the security and stability of your Linux systems.
Timeline
Published on: 09/27/2024 13:15:17 UTC
Last modified on: 12/19/2024 09:24:56 UTC