CVE-2022-49227: 
Linux Kernel vulnerability analysis and mitigation

CVE-2022-49227 affects the Linux kernel's Intel IGC (Intel Gigabit Ethernet Controller) driver. The vulnerability was discovered when changing RX ring parameters using ethtool, which triggers kernel warnings due to improper handling of XDP (eXpress Data Path) queue information registration. The issue was identified and resolved in early 2022 (Kernel Git).

The vulnerability occurs in the igc_ethtool_set_ringparam() function which copies the igc_ring structure but fails to reset the xdp_rxq_info member before calling igc_setup_rx_resources(). This results in calling xdp_rxq_info_reg() with an already registered xdp_rxq_info, triggering kernel warnings. The issue stems from a bug introduced in commit 73f1071c1d29 ("igc: Add support for XDP_TX action") (Kernel Git).

When exploited, this vulnerability causes kernel warnings and potential system instability when attempting to change RX ring parameters on Intel Gigabit Ethernet Controllers using the igc driver (Kernel Git).

The vulnerability can be triggered by using the ethtool command to change RX ring parameters (e.g., ethtool -G eth0 rx 1024) on systems using the affected Intel IGC driver (Kernel Git).

The issue has been fixed by adding proper XDP RX-queue info handling in igc_setup_rx_resources(). The fix includes checking if the xdp_rxq_info is registered and unregistering it before attempting to register it again (Kernel Git).