tracing/mmiotrace: Add NULL check for mmio_trace_array in logging functions

Summary

In the Linux kernel, the following vulnerability has been resolved: tracing/mmiotrace: Add NULL check for mmio_trace_array in logging functions mmio_trace_rw() and mmio_trace_mapping() retrieve mmio_trace_array into tr and pass it to __trace_mmiotrace_rw() and __trace_mmiotrace_map(). If these functions are invoked while mmio_trace_array is NULL (e.g. before initialization or after disabled), accessing tr->array_buffer.buffer will result in a NULL pointer dereference crash. Fix this by adding an explicit NULL check for tr at the beginning of __trace_mmiotrace_rw() and __trace_mmiotrace_map().

Timeline

1. Aug 28, 2026, 6:52 AM UTCCVE published
2. Sep 14, 2026, 11:58 AM UTCRecord last updated

Affected versions

• Linux Linux

  Version range not reported

• Linux Linux

  2.6.27

References 8