CVE-2023-53649: 
Linux Kernel vulnerability analysis and mitigation

A memory leak vulnerability was discovered in the Linux kernel's perf trace functionality. The issue occurs in the evsel->priv area where memory allocated for non-syscall tracepoints was not being properly freed. The vulnerability was identified through memory leak detection using Address Sanitizer (ASAN) (NVD).

The vulnerability stems from a logic error in the memory management of the perf trace subsystem. In commit 3cb4d5e00e037c70 ("perf trace: Free syscall tp fields in evsel->priv"), the code only freed memory if strcmp(evsel->tp_format->system, "syscalls") returned zero, while the corresponding initialization of evsel->priv was being performed if it was not zero. This mismatch in conditions led to memory leaks of 40 bytes per allocation in certain code paths (NVD).

The vulnerability results in memory leaks of 40 bytes per allocation when using the perf trace functionality. While the immediate impact per instance is relatively small, repeated occurrences could lead to cumulative memory consumption over time (NVD).

The issue has been resolved by modifying the code to free evsel->priv if it was set, regardless of the tracepoint system type. The fix also utilizes the pre-existing evsel_trace__delete() function for proper cleanup (NVD).