From fd0fb14e613f15a7d1fbde86bf371a72d8dfe3b8 Mon Sep 17 00:00:00 2001
From: Carlos O'Donell <carlos@systemhalted.org>
Date: Wed, 29 Nov 2017 22:36:39 -0800
Subject: [PATCH 75/79] nss: Fix invalid enum nss_status return values.
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The upstream glibc test nss/bug17079 covers several cases where the
NSS infrastructure passes invalid pointers to NSS plugins. The plugins
should return correct results for the invalid values e.g. ERANGE,
but it should do so by setting *errnop to the error and returning
NSS_STATUS_TRYAGAIN. This commit fixes the group, netgroup, passwd
and service handling code to correctly return ERANGE in *errnop
and NSS_TATUS_TRYAGAIN in the case of invalid buffer (NULL) or
zero sized buffer length. This fixes the nss/bug17079 regression test
when run in a test configuration with sss enabled for any of the
above mentioned services.

Upstream glibc bug:
Bug 22530 - FAIL: nss/bug17079 due to _nss_sss_getpwuid_r
https://sourceware.org/bugzilla/show_bug.cgi?id=22530

Merges: https://pagure.io/SSSD/sssd/pull-request/3561

Signed-off-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com>
---
 src/sss_client/nss_group.c    | 10 ++++++++--
 src/sss_client/nss_netgroup.c |  5 ++++-
 src/sss_client/nss_passwd.c   | 10 ++++++++--
 src/sss_client/nss_services.c | 15 ++++++++++++---
 4 files changed, 32 insertions(+), 8 deletions(-)

diff --git a/src/sss_client/nss_group.c b/src/sss_client/nss_group.c
index 42fba6242d23fc1d52cfd7be10cf10383010f091..054f30e13f8d5f8300a3e63c9035b98d30473c0e 100644
--- a/src/sss_client/nss_group.c
+++ b/src/sss_client/nss_group.c
@@ -522,7 +522,10 @@ enum nss_status _nss_sss_getgrgid_r(gid_t gid, struct group *result,
     int ret;
 
     /* Caught once glibc passing in buffer == 0x0 */
-    if (!buffer || !buflen) return ERANGE;
+    if (!buffer || !buflen) {
+	*errnop = ERANGE;
+	return NSS_STATUS_TRYAGAIN;
+    }
 
     ret = sss_nss_mc_getgrgid(gid, result, buffer, buflen);
     switch (ret) {
@@ -655,7 +658,10 @@ static enum nss_status internal_getgrent_r(struct group *result,
     int ret;
 
     /* Caught once glibc passing in buffer == 0x0 */
-    if (!buffer || !buflen) return ERANGE;
+    if (!buffer || !buflen) {
+	*errnop = ERANGE;
+	return NSS_STATUS_TRYAGAIN;
+    }
 
     /* if there are leftovers return the next one */
     if (sss_nss_getgrent_data.data != NULL &&
diff --git a/src/sss_client/nss_netgroup.c b/src/sss_client/nss_netgroup.c
index 8594fc460514d6f92e786605168fa7d15c7ee913..3a1834a311e6658c6160b5f95a01434fed69ad1c 100644
--- a/src/sss_client/nss_netgroup.c
+++ b/src/sss_client/nss_netgroup.c
@@ -231,7 +231,10 @@ static enum nss_status internal_getnetgrent_r(struct __netgrent *result,
     int ret;
 
     /* Caught once glibc passing in buffer == 0x0 */
-    if (!buffer || !buflen) return ERANGE;
+    if (!buffer || !buflen) {
+	*errnop = ERANGE;
+	return NSS_STATUS_TRYAGAIN;
+    }
 
     /* If we're already processing result data, continue to
      * return it.
diff --git a/src/sss_client/nss_passwd.c b/src/sss_client/nss_passwd.c
index 61e2a567e684fbc7664b5d425e81cfa28a98e845..5b1c2ce66b0954bc304dfb458f509defa8eed889 100644
--- a/src/sss_client/nss_passwd.c
+++ b/src/sss_client/nss_passwd.c
@@ -251,7 +251,10 @@ enum nss_status _nss_sss_getpwuid_r(uid_t uid, struct passwd *result,
     int ret;
 
     /* Caught once glibc passing in buffer == 0x0 */
-    if (!buffer || !buflen) return ERANGE;
+    if (!buffer || !buflen) {
+	*errnop = ERANGE;
+	return NSS_STATUS_TRYAGAIN;
+    }
 
     ret = sss_nss_mc_getpwuid(uid, result, buffer, buflen);
     switch (ret) {
@@ -376,7 +379,10 @@ static enum nss_status internal_getpwent_r(struct passwd *result,
     int ret;
 
     /* Caught once glibc passing in buffer == 0x0 */
-    if (!buffer || !buflen) return ERANGE;
+    if (!buffer || !buflen) {
+	*errnop = ERANGE;
+	return NSS_STATUS_TRYAGAIN;
+    }
 
     /* if there are leftovers return the next one */
     if (sss_nss_getpwent_data.data != NULL &&
diff --git a/src/sss_client/nss_services.c b/src/sss_client/nss_services.c
index 64e0b43e1643e4e76d2381a6b062335c3d513a21..161dad9ae27f822b40af8368e5af38b020d6549a 100644
--- a/src/sss_client/nss_services.c
+++ b/src/sss_client/nss_services.c
@@ -177,7 +177,10 @@ _nss_sss_getservbyname_r(const char *name,
     int ret;
 
     /* Caught once glibc passing in buffer == 0x0 */
-    if (!buffer || !buflen) return ERANGE;
+    if (!buffer || !buflen) {
+	*errnop = ERANGE;
+	return NSS_STATUS_TRYAGAIN;
+    }
 
     ret = sss_strnlen(name, SSS_NAME_MAX, &name_len);
     if (ret != 0) {
@@ -278,7 +281,10 @@ _nss_sss_getservbyport_r(int port, const char *protocol,
     int ret;
 
     /* Caught once glibc passing in buffer == 0x0 */
-    if (!buffer || !buflen) return ERANGE;
+    if (!buffer || !buflen) {
+	*errnop = ERANGE;
+	return NSS_STATUS_TRYAGAIN;
+    }
 
     if (protocol) {
         ret = sss_strnlen(protocol, SSS_NAME_MAX, &proto_len);
@@ -411,7 +417,10 @@ static enum nss_status internal_getservent_r(struct servent *result,
     int ret;
 
     /* Caught once glibc passing in buffer == 0x0 */
-    if (!buffer || !buflen) return ERANGE;
+    if (!buffer || !buflen) {
+	*errnop = ERANGE;
+	return NSS_STATUS_TRYAGAIN;
+    }
 
     /* if there are leftovers return the next one */
     if (sss_nss_getservent_data.data != NULL &&
-- 
2.15.1