5013f454a3
Trace events record data into the ring buffer at the time of the event. The trace event has a printf logic to display the recorded data at a much later time when the user reads the trace file. This makes using dereferencing pointers unsafe if the dereferenced pointer points to the original source. The safe way to handle this is to create an array within the trace event and copy the source into the array. Then the dereference pointer may point to that array. As this is a easy mistake to make, a check is added to examine all trace event print fmts to make sure that they are safe to use. This only checks the various %p* dereferenced pointers like %pB, %pR, etc. It does not handle dereferencing of strings, as there are some use cases that are OK to dereference the source. That will be dealt with differently. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.