CVE-2021-4453: 
Linux Kernel vulnerability analysis and mitigation

CVE-2021-4453 is a memory leak vulnerability in the Linux kernel's AMD GPU driver, specifically in the GStreamer component. The vulnerability was discovered in 2021 and affects the memory management of gpu_metrics_table in the renoir_init_smc_tables() function (Ubuntu Security).

The vulnerability occurs when memory is allocated for gpu_metrics_table in renoir_init_smc_tables() but not properly freed in smu_v12_0_fini_smc_tables() function. This results in a memory leak in the AMD GPU driver. The vulnerability has been assigned a CVSS score of 7.8, indicating a high severity level with local attack vector and low attack complexity (Oracle Security).

The vulnerability could lead to memory resource exhaustion over time as allocated memory is not properly freed, potentially affecting system stability and performance. The impact is primarily focused on systems running AMD GPUs with the affected driver component (Ubuntu Security).

The vulnerability requires local access to exploit, with no requirement for special privileges but does require user interaction. The attack complexity is rated as low, making it relatively straightforward to exploit for an attacker with local access (Oracle Security).

The issue has been fixed by adding proper memory deallocation code in the smu_v12_0_fini_smc_tables() function. The fix includes adding 'kfree(smu_table->gpu_metrics_table)' and setting the pointer to NULL after freeing (Kernel Git).