Created attachment 3208 [details]
patch to fix memory leak

Note: This is my first contribution to the openssh source and I'm porting my findings from a macOS/Windows port back to the original source. So please be gentle with my possible wrongdoings and errors.


In any case, I think this should be pretty straightforward:

In channels.c there is the channel_init_channels() function, which initially callocates memory for the sc structure and immediately also callocates and fills the sc->channel_pre and sc->channel_post pointer members.

Then, after a few lines of code, it finally calls the channel_handler_init(sc) function.

Now, the channel channel_handler_init() also callocates memory for pre and post and finally assigns its pointers into the sc struct pointer members.

        sc->channel_pre = pre;
        sc->channel_post = post;

However, at this point, sc->channel_pre and sc->channel_post are already filled with the pointers to the memory blocks which channel_init_channels() had allocated.

Thus these pointers get lost and the memory blocks leak.


Proposal: don't have chanell_init_channel() allocate these.  Let channel_init_channels() do it.


A patch is attached.