Re: [dpdk-dev] [PATCH] eal: fix strdup usages in internal config

[Thomas Monjalon <thomas@monjalon.net>]

10/01/2019 14:38, Anatoly Burakov:
> Currently, we use strdup in a few places to store command-line
> parameter values for certain internal config values. There are
> several issues with that.
> 
> First of all, they're never freed, so memory ends up leaking
> either after EAL exit, or when these command-line options are
> supplied multiple times.
> 
> Second of all, they're defined as `const char *`, so they
> *cannot* be freed even if we wanted to.
> 
> Finally, strdup may return NULL, which will be stored in the
> config. For most fields, NULL is a valid value, but for the
> default prefix, the value is always expected to be valid.
> 
> To fix all of this, three things are done. First, we change
> the definitions of these values to `char *` as opposed to
> `const char *`. This does not break the ABI, and previous
> code assumes constness (which is more restrictive), so it's
> safe to do so.
> 
> Then, fix all usages of strdup to check return value, and add
> a cleanup function that will free the memory occupied by
> these strings, as well as freeing them before assigning a new
> value to prevent leaks when parameter is specified multiple
> times.
> 
> And finally, add an internal API to query hugefile prefix, so
> that, absent of a valid value, a default value will be
> returned, and also fix up all usages of hugefile prefix to
> use this API instead of accessing hugefile prefix directly.
> 
> Bugzilla ID: 108
> 
> Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>

Applied, thanks