[PATCH] Fix use of half-initialized result in resolver when using nscd

Andreas Schwab schwab@suse.de
Thu Mar 20 14:48:00 GMT 2014


This fixes a bug in the way the results from __nscd_getai are collected:
for every returned result a new entry is first added to the
gaih_addrtuple list, but if that result doesn't match the request this
entry remains uninitialized.  So for this non-matching result an extra
result with uninitialized content is returned.

Andreas.

	* sysdeps/posix/getaddrinfo.c (gaih_inet): Properly skip over
	non-matching result from nscd.
---
 sysdeps/posix/getaddrinfo.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c
index e1a399b..3385bed 100644
--- a/sysdeps/posix/getaddrinfo.c
+++ b/sysdeps/posix/getaddrinfo.c
@@ -710,6 +710,14 @@ gaih_inet (const char *name, const struct gaih_service *service,
 		  struct gaih_addrtuple *addrfree = addrmem;
 		  for (int i = 0; i < air->naddrs; ++i)
 		    {
+		      if (!((air->family[i] == AF_INET
+			     && req->ai_family == AF_INET6
+			     && (req->ai_flags & AI_V4MAPPED) != 0)
+			    || req->ai_family == AF_UNSPEC
+			    || air->family[i] == req->ai_family))
+			/* Skip over non-matching result.  */
+			continue;
+
 		      socklen_t size = (air->family[i] == AF_INET
 					? INADDRSZ : IN6ADDRSZ);
 		      if (*pat == NULL)
-- 
1.9.1

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."



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