CVE-2022-49410

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> tracing: Fix potential double free in create_var_ref()<br /> <br /> In create_var_ref(), init_var_ref() is called to initialize the fields<br /> of variable ref_field, which is allocated in the previous function call<br /> to create_hist_field(). Function init_var_ref() allocates the<br /> corresponding fields such as ref_field-&gt;system, but frees these fields<br /> when the function encounters an error. The caller later calls<br /> destroy_hist_field() to conduct error handling, which frees the fields<br /> and the variable itself. This results in double free of the fields which<br /> are already freed in the previous function.<br /> <br /> Fix this by storing NULL to the corresponding fields when they are freed<br /> in init_var_ref().