Memory leak on multiple calls to loadCACert and others on WiFiClientSecure

[sguarin]

If you have a system that can accept certs configuration, then multiple calls to loadCACert or related functions will not reutilize the memory assigned.

https://github.com/sguarin/arduino-esp32/blob/caa8d07aafa04441bb85e6046a795249c01d9e39/libraries/WiFiClientSecure/src/WiFiClientSecure.cpp#L304

_streamLoad()
allocates memory for new certificates. A better approach should be using realloc().

https://github.com/sguarin/arduino-esp32/blob/caa8d07aafa04441bb85e6046a795249c01d9e39/libraries/WiFiClientSecure/src/WiFiClientSecure.cpp#L290

[sguarin]

This temporary fix worked for me.
But I think the memory pointer should not be static and should live on the class.

https://github.com/espressif/arduino-esp32/compare/master...sguarin:fix_streamLoad?expand=1

[TD-er]

Just a repeat of the comment I placed with that commit:

You're not checking the return value of realloc.
If the return value is not a nullptr, you should assign it to *destPtr.
If it is a nullptr, it depends on the C++ version whether it was a failed alloc or not changed (e.g. size was the same)

And no need to check if *destPtr is a nullptr, as realloc called with a nullptr acts like malloc.

[sguarin]

You are right. Thanks!