CVE-2021-29265: 
Linux Kernel vulnerability analysis and mitigation

CVE-2021-29265 is a vulnerability discovered in the Linux kernel before version 5.11.7, specifically in the usbipsockfdstore function within drivers/usb/usbip/stub_dev.c. The vulnerability was disclosed on March 26, 2021, affecting the USB/IP driver implementation. The issue stems from race conditions during the update of local and shared status in the stub-up sequence (NVD, Ubuntu).

The vulnerability occurs in the USB/IP host (server) implementation where race conditions exist in updating the local and shared status. The issue specifically involves the stub-up sequence having race conditions during updates of the local and shared status, which can lead to a General Protection Fault (GPF). The vulnerability has been assigned a CVSS v3.1 Base Score of 4.7 (Medium) with vector string CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H (NVD).

When exploited, this vulnerability allows attackers to cause a denial of service condition through a General Protection Fault (GPF). The impact is primarily focused on system availability, with no direct impact on confidentiality or integrity (NVD, Ubuntu).

The vulnerability has been fixed in Linux kernel version 5.11.7 through a patch that addresses the race conditions in the stub-up sequence. The fix includes proper handling of thread creation errors and synchronization of local and shared states. Various Linux distributions have also released patches for their respective versions, including Ubuntu and Debian (Kernel Patch).