commit 1cef1b19089528db11f221e938f60b9b048945d7
Author: Andreas Schwab <schwab@suse.de>
Date: Thu Mar 21 15:50:27 2013 +0100
Fix stack overflow in getaddrinfo with many results
diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c
index d95c2d1..2309281 100644
--- a/sysdeps/posix/getaddrinfo.c
+++ b/sysdeps/posix/getaddrinfo.c
@@ -2489,11 +2489,27 @@ getaddrinfo (const char *name, const char *service,
__typeof (once) old_once = once;
__libc_once (once, gaiconf_init);
/* Sort results according to RFC 3484. */
- struct sort_result results[nresults];
- size_t order[nresults];
+ struct sort_result *results;
+ size_t *order;
struct addrinfo *q;
struct addrinfo *last = NULL;
char *canonname = NULL;
+ bool malloc_results;
+
+ malloc_results
+ = !__libc_use_alloca (nresults * (sizeof (*results) + sizeof (size_t)));
+ if (malloc_results)
+ {
+ results = malloc (nresults * (sizeof (*results) + sizeof (size_t)));
+ if (results == NULL)
+ {
+ __free_in6ai (in6ai);
+ return EAI_MEMORY;
+ }
+ }
+ else
+ results = alloca (nresults * (sizeof (*results) + sizeof (size_t)));
+ order = (size_t *) (results + nresults);
/* Now we definitely need the interface information. */
if (! check_pf_called)
@@ -2664,6 +2680,9 @@ getaddrinfo (const char *name, const char *service,
/* Fill in the canonical name into the new first entry. */
p->ai_canonname = canonname;
+
+ if (malloc_results)
+ free (results);
}
__free_in6ai (in6ai);