CVE-2024-42246: net, sunrpc: Remap EPERM in case of connection failure in xs_tcp_setup_socket
In the Linux kernel, the following vulnerability has been resolved:
net, sunrpc: Remap EPERM in case of connection failure in xstcpsetupsocket
When using a BPF program on kernelconnect(), the call can return -EPERM. This causes xstcpsetupsocket() to loop forever, filling up the syslog and causing the kernel to potentially freeze up.
Neil suggested:
This will propagate -EPERM up into other layers which might not be ready to handle it. It might be safer to map EPERM to an error we would be more likely to expect from the network system - such as ECONNREFUSED or ENETDOWN.
ECONNREFUSED as error seems reasonable. For programs setting a different error can be out of reach (see handling in 4fbac77d2d09) in particular on kernels which do not have f10d05966196 ("bpf: Make BPFPROGRUNARRAY return -err instead of allow boolean"), thus given that it is better to simply remap for consistent behavior. UDP does handle EPERM in xsudpsendrequest().
Other sources
Linux Kernel is vulnerable to a denial of service, caused by connection failure in xstcpsetupsocket. A local authenticated attacker could exploit this vulnerability to cause a denial of service.
— IBM
net sunrpc: Remap EPERM in case of connection failure in xstcpsetupsocket
— Microsoft
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2024-42246?
CVE-2024-42246 is classified with a moderate severity level.
How do I fix CVE-2024-42246?
To remediate CVE-2024-42246, upgrade to the specified patched versions of the Linux kernel provided in the release notes.
What software versions are affected by CVE-2024-42246?
CVE-2024-42246 affects Linux kernel versions up to 5.10.223-1 and various other versions listed in the advisory.
What is the impact of CVE-2024-42246?
CVE-2024-42246 can lead to a denial of service due to an infinite loop in the xs_tcp_setup_socket function.
Is it necessary to reboot after applying the fix for CVE-2024-42246?
Yes, a system reboot is typically required after upgrading the kernel to ensure the changes take effect.