commit a5bd2e10e0c25b80286dc36068e22a4cb4893af0

Author: Siddhesh Poyarekar <siddhesh@sourceware.org>

Date:   Tue Aug 3 21:11:03 2021 +0530

    gaiconf_init: Avoid double-free in label and precedence lists

    labellist and precedencelist could get freed a second time if there

    are allocation failures, so set them to NULL to avoid a double-free.

    Reviewed-by: Arjun Shankar <arjun@redhat.com>

    (cherry picked from commit 77a34079d8f3d63b61543bf3af93043f8674e4c4)

diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c

index 838a68f0229b5aa8..43dfc6739e350a58 100644

--- a/sysdeps/posix/getaddrinfo.c

+++ b/sysdeps/posix/getaddrinfo.c

@@ -2008,6 +2008,7 @@ gaiconf_init (void)

 	      l = l->next;

 	    }

 	  free_prefixlist (labellist);

+	  labellist = NULL;

 	  /* Sort the entries so that the most specific ones are at

 	     the beginning.  */

@@ -2046,6 +2047,7 @@ gaiconf_init (void)

 	      l = l->next;

 	    }

 	  free_prefixlist (precedencelist);

+	  precedencelist = NULL;

 	  /* Sort the entries so that the most specific ones are at

 	     the beginning.  */