Potential memory leak in ares_init.c - init_by_defaults()

[lthuressonhs]

There is a potential memory leak when init_by_defaults() function returns with error.
Fixed it with this patch

--- src/lib/ares_init.c.org 2024-02-23 08:23:02.000000000 +0100
+++ src/lib/ares_init.c 2024-03-12 16:10:13.107757585 +0100
@@ -262,12 +262,10 @@

error:
if (rc) {

• if (channel->domains && channel->domains[0]) {

•  ares_free(channel->domains[0]);
  

• }
  if (channel->domains) {

•  ares_free(channel->domains);
  

•  ares__strsplit_free(channel->domains, channel->ndomains);
   channel->domains = NULL;
  

•  channel->ndomains = 0;
  

  }

[lthuressonhs]

That formatting in the previous comment didn't turn out well...
I hope you can see the problem anyway.

[bradh352]

Yeah, I see what you're getting at even with the bad formatting. Apparently the function didn't take into account that it may not be the one that allocated domains. In fact, I'm not even sure why this function is trying to clean up at all, if it fails, the caller ends up calling ares_destroy() which does the cleanup properly.

[bradh352]

Fixed in 06a20d7

[lthuressonhs]

That was fast. Thanks! /Leif Leif Thuresson +46 73 363 00 46 [https://static.fortra.com/email-signatures/fta-triangle-green-9x8.png] fortra.com<https://www.fortra.com/>

…

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