CVE-2023-53383: 
Linux Kernel vulnerability analysis and mitigation

CVE-2023-53383 is a vulnerability in the Linux kernel related to the NVIDIA T241-FABRIC-4 erratum that affects the Generic Interrupt Controller (GIC) behavior. The issue was disclosed in September 2025 and impacts NVIDIA server platforms using more than two T241 chips interconnected (NVD).

The vulnerability occurs when multiple packets from different GICs are incorrectly interleaved at the target chip. Each T241 chip supports 320 ESPIs, and the issue manifests when multiple transactions are received simultaneously from different sources. The problem specifically affects inter-socket AXI4 Stream packets with multiple transfers, which may be incorrectly interleaved by the fabric when presented to the ARM Generic Interrupt Controller. This affects various GICv3 commands including register reads from GICDI* and GICDN*, register writes to 64-bit GICD registers, and ITS command MOVALL (NVD).

The vulnerability can lead to GIC state corruption, resulting in kernel panics and unexpected system behavior. The issue particularly affects system configurations with more than 2 sockets that require multi-transfer packets to be sent over inter-socket AXI4 Stream interface between GIC instances on different sockets. GICv4 functionality cannot be supported, while GICv3 can only be supported with specific workarounds (NVD).

The fix involves implementing a workaround that ensures read accesses to the GICDIn{E} registers are directed to the chip that owns the SPI, and disabling GICv4.x features. To simplify code changes, the gicconfigureirq() function uses the same alias region for both read and write operations to GICDICFGR. Single and Dual socket configurations are not impacted by this issue and continue to support both GICv3 and GICv4 (NVD).