From ecc4a34067ed7c03b9ee710aa5e5976fded48c2a Mon Sep 17 00:00:00 2001

From: Lennart Poettering <lennart@poettering.net>

Date: Fri, 18 Jan 2019 20:13:55 +0100

Subject: [PATCH] nss: unportect errno before writing to NSS' *errnop

Fixes: #11321

(cherry picked from commit cdccd29f39cd20cb2a8b71e50445eb839f076331)

Resolves: #1691691

---

 src/nss-myhostname/nss-myhostname.c | 13 +++++++++++++

 src/nss-mymachines/nss-mymachines.c | 13 +++++++++++++

 src/nss-resolve/nss-resolve.c       |  8 ++++++++

 src/nss-systemd/nss-systemd.c       | 10 ++++++++++

 4 files changed, 44 insertions(+)

diff --git a/src/nss-myhostname/nss-myhostname.c b/src/nss-myhostname/nss-myhostname.c

index 5abc0c91bf..e491351dee 100644

--- a/src/nss-myhostname/nss-myhostname.c

+++ b/src/nss-myhostname/nss-myhostname.c

@@ -74,6 +74,7 @@ enum nss_status _nss_myhostname_gethostbyname4_r(

         } else {

                 hn = gethostname_malloc();

                 if (!hn) {

+                        UNPROTECT_ERRNO;

                         *errnop = ENOMEM;

                         *h_errnop = NO_RECOVERY;

                         return NSS_STATUS_TRYAGAIN;

@@ -96,6 +97,7 @@ enum nss_status _nss_myhostname_gethostbyname4_r(

         l = strlen(canonical);

         ms = ALIGN(l+1) + ALIGN(sizeof(struct gaih_addrtuple)) * (n_addresses > 0 ? n_addresses : 2);

         if (buflen < ms) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 *h_errnop = NETDB_INTERNAL;

                 return NSS_STATUS_TRYAGAIN;

@@ -186,6 +188,8 @@ static enum nss_status fill_in_hostent(

         assert(errnop);

         assert(h_errnop);

+        PROTECT_ERRNO;

+

         alen = FAMILY_ADDRESS_SIZE(af);

         for (a = addresses, n = 0, c = 0; n < n_addresses; a++, n++)

@@ -202,6 +206,7 @@ static enum nss_status fill_in_hostent(

                 (c > 0 ? c+1 : 2) * sizeof(char*);

         if (buflen < ms) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 *h_errnop = NETDB_INTERNAL;

                 return NSS_STATUS_TRYAGAIN;

@@ -321,6 +326,7 @@ enum nss_status _nss_myhostname_gethostbyname3_r(

                 af = AF_INET;

         if (!IN_SET(af, AF_INET, AF_INET6)) {

+                UNPROTECT_ERRNO;

                 *errnop = EAFNOSUPPORT;

                 *h_errnop = NO_DATA;

                 return NSS_STATUS_UNAVAIL;

@@ -343,6 +349,7 @@ enum nss_status _nss_myhostname_gethostbyname3_r(

         } else {

                 hn = gethostname_malloc();

                 if (!hn) {

+                        UNPROTECT_ERRNO;

                         *errnop = ENOMEM;

                         *h_errnop = NO_RECOVERY;

                         return NSS_STATUS_TRYAGAIN;

@@ -362,6 +369,8 @@ enum nss_status _nss_myhostname_gethostbyname3_r(

                 local_address_ipv4 = LOCALADDRESS_IPV4;

         }

+        UNPROTECT_ERRNO;

+

         return fill_in_hostent(

                         canonical, additional,

                         af,

@@ -401,12 +410,14 @@ enum nss_status _nss_myhostname_gethostbyaddr2_r(

         assert(h_errnop);

         if (!IN_SET(af, AF_INET, AF_INET6)) {

+                UNPROTECT_ERRNO;

                 *errnop = EAFNOSUPPORT;

                 *h_errnop = NO_DATA;

                 return NSS_STATUS_UNAVAIL;

         }

         if (len != FAMILY_ADDRESS_SIZE(af)) {

+                UNPROTECT_ERRNO;

                 *errnop = EINVAL;

                 *h_errnop = NO_RECOVERY;

                 return NSS_STATUS_UNAVAIL;

@@ -461,6 +472,7 @@ found:

         if (!canonical || additional_from_hostname) {

                 hn = gethostname_malloc();

                 if (!hn) {

+                        UNPROTECT_ERRNO;

                         *errnop = ENOMEM;

                         *h_errnop = NO_RECOVERY;

                         return NSS_STATUS_TRYAGAIN;

@@ -472,6 +484,7 @@ found:

                         additional = hn;

         }

+        UNPROTECT_ERRNO;

         return fill_in_hostent(

                         canonical, additional,

                         af,

diff --git a/src/nss-mymachines/nss-mymachines.c b/src/nss-mymachines/nss-mymachines.c

index 9b81cd9ad1..af9f0bf41f 100644

--- a/src/nss-mymachines/nss-mymachines.c

+++ b/src/nss-mymachines/nss-mymachines.c

@@ -134,6 +134,7 @@ enum nss_status _nss_mymachines_gethostbyname4_r(

         l = strlen(name);

         ms = ALIGN(l+1) + ALIGN(sizeof(struct gaih_addrtuple)) * c;

         if (buflen < ms) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 *h_errnop = NETDB_INTERNAL;

                 return NSS_STATUS_TRYAGAIN;

@@ -208,6 +209,7 @@ enum nss_status _nss_mymachines_gethostbyname4_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         *h_errnop = NO_DATA;

         return NSS_STATUS_UNAVAIL;

@@ -289,6 +291,7 @@ enum nss_status _nss_mymachines_gethostbyname3_r(

         ms = ALIGN(l+1) + c * ALIGN(alen) + (c+2) * sizeof(char*);

         if (buflen < ms) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 *h_errnop = NETDB_INTERNAL;

                 return NSS_STATUS_TRYAGAIN;

@@ -372,6 +375,7 @@ enum nss_status _nss_mymachines_gethostbyname3_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         *h_errnop = NO_DATA;

         return NSS_STATUS_UNAVAIL;

@@ -455,6 +459,7 @@ enum nss_status _nss_mymachines_getpwnam_r(

         l = strlen(name);

         if (buflen < l+1) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 return NSS_STATUS_TRYAGAIN;

         }

@@ -472,6 +477,7 @@ enum nss_status _nss_mymachines_getpwnam_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         return NSS_STATUS_UNAVAIL;

 }

@@ -530,6 +536,7 @@ enum nss_status _nss_mymachines_getpwuid_r(

                 return NSS_STATUS_NOTFOUND;

         if (snprintf(buffer, buflen, "vu-%s-" UID_FMT, machine, (uid_t) mapped) >= (int) buflen) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 return NSS_STATUS_TRYAGAIN;

         }

@@ -545,6 +552,7 @@ enum nss_status _nss_mymachines_getpwuid_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         return NSS_STATUS_UNAVAIL;

 }

@@ -623,6 +631,7 @@ enum nss_status _nss_mymachines_getgrnam_r(

         l = sizeof(char*) + strlen(name) + 1;

         if (buflen < l) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 return NSS_STATUS_TRYAGAIN;

         }

@@ -638,6 +647,7 @@ enum nss_status _nss_mymachines_getgrnam_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         return NSS_STATUS_UNAVAIL;

 }

@@ -696,12 +706,14 @@ enum nss_status _nss_mymachines_getgrgid_r(

                 return NSS_STATUS_NOTFOUND;

         if (buflen < sizeof(char*) + 1) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 return NSS_STATUS_TRYAGAIN;

         }

         memzero(buffer, sizeof(char*));

         if (snprintf(buffer + sizeof(char*), buflen - sizeof(char*), "vg-%s-" GID_FMT, machine, (gid_t) mapped) >= (int) buflen) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 return NSS_STATUS_TRYAGAIN;

         }

@@ -714,6 +726,7 @@ enum nss_status _nss_mymachines_getgrgid_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         return NSS_STATUS_UNAVAIL;

 }

diff --git a/src/nss-resolve/nss-resolve.c b/src/nss-resolve/nss-resolve.c

index b2bb698ded..145dbdd60c 100644

--- a/src/nss-resolve/nss-resolve.c

+++ b/src/nss-resolve/nss-resolve.c

@@ -167,6 +167,7 @@ enum nss_status _nss_resolve_gethostbyname4_r(

         l = strlen(canonical);

         ms = ALIGN(l+1) + ALIGN(sizeof(struct gaih_addrtuple)) * c;

         if (buflen < ms) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 *h_errnop = NETDB_INTERNAL;

                 return NSS_STATUS_TRYAGAIN;

@@ -248,6 +249,7 @@ enum nss_status _nss_resolve_gethostbyname4_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         *h_errnop = NO_RECOVERY;

         return ret;

@@ -340,6 +342,7 @@ enum nss_status _nss_resolve_gethostbyname3_r(

         ms = ALIGN(l+1) + c * ALIGN(alen) + (c+2) * sizeof(char*);

         if (buflen < ms) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 *h_errnop = NETDB_INTERNAL;

                 return NSS_STATUS_TRYAGAIN;

@@ -431,6 +434,7 @@ enum nss_status _nss_resolve_gethostbyname3_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         *h_errnop = NO_RECOVERY;

         return ret;

@@ -468,12 +472,14 @@ enum nss_status _nss_resolve_gethostbyaddr2_r(

         assert(h_errnop);

         if (!IN_SET(af, AF_INET, AF_INET6)) {

+                UNPROTECT_ERRNO;

                 *errnop = EAFNOSUPPORT;

                 *h_errnop = NO_DATA;

                 return NSS_STATUS_UNAVAIL;

         }

         if (len != FAMILY_ADDRESS_SIZE(af)) {

+                UNPROTECT_ERRNO;

                 *errnop = EINVAL;

                 *h_errnop = NO_RECOVERY;

                 return NSS_STATUS_UNAVAIL;

@@ -547,6 +553,7 @@ enum nss_status _nss_resolve_gethostbyaddr2_r(

               c * sizeof(char*);        /* pointers to aliases, plus trailing NULL */

         if (buflen < ms) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 *h_errnop = NETDB_INTERNAL;

                 return NSS_STATUS_TRYAGAIN;

@@ -607,6 +614,7 @@ enum nss_status _nss_resolve_gethostbyaddr2_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         *h_errnop = NO_RECOVERY;

         return ret;

diff --git a/src/nss-systemd/nss-systemd.c b/src/nss-systemd/nss-systemd.c

index f554828d49..f8db27ae27 100644

--- a/src/nss-systemd/nss-systemd.c

+++ b/src/nss-systemd/nss-systemd.c

@@ -210,6 +210,7 @@ enum nss_status _nss_systemd_getpwnam_r(

         l = strlen(name);

         if (buflen < l+1) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 return NSS_STATUS_TRYAGAIN;

         }

@@ -227,6 +228,7 @@ enum nss_status _nss_systemd_getpwnam_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         return NSS_STATUS_UNAVAIL;

 }

@@ -310,6 +312,7 @@ enum nss_status _nss_systemd_getpwuid_r(

         l = strlen(translated) + 1;

         if (buflen < l) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 return NSS_STATUS_TRYAGAIN;

         }

@@ -327,6 +330,7 @@ enum nss_status _nss_systemd_getpwuid_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         return NSS_STATUS_UNAVAIL;

 }

@@ -408,6 +412,7 @@ enum nss_status _nss_systemd_getgrnam_r(

         l = sizeof(char*) + strlen(name) + 1;

         if (buflen < l) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 return NSS_STATUS_TRYAGAIN;

         }

@@ -423,6 +428,7 @@ enum nss_status _nss_systemd_getgrnam_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         return NSS_STATUS_UNAVAIL;

 }

@@ -506,6 +512,7 @@ enum nss_status _nss_systemd_getgrgid_r(

         l = sizeof(char*) + strlen(translated) + 1;

         if (buflen < l) {

+                UNPROTECT_ERRNO;

                 *errnop = ERANGE;

                 return NSS_STATUS_TRYAGAIN;

         }

@@ -521,6 +528,7 @@ enum nss_status _nss_systemd_getgrgid_r(

         return NSS_STATUS_SUCCESS;

 fail:

+        UNPROTECT_ERRNO;

         *errnop = -r;

         return NSS_STATUS_UNAVAIL;

 }

@@ -740,6 +748,7 @@ enum nss_status _nss_systemd_getpwent_r(struct passwd *result, char *buffer, siz

         LIST_FOREACH(entries, p, getpwent_data.position) {

                 len = strlen(p->name) + 1;

                 if (buflen < len) {

+                        UNPROTECT_ERRNO;

                         *errnop = ERANGE;

                         ret = NSS_STATUS_TRYAGAIN;

                         goto finalize;

@@ -791,6 +800,7 @@ enum nss_status _nss_systemd_getgrent_r(struct group *result, char *buffer, size

         LIST_FOREACH(entries, p, getgrent_data.position) {

                 len = sizeof(char*) + strlen(p->name) + 1;

                 if (buflen < len) {

+                        UNPROTECT_ERRNO;

                         *errnop = ERANGE;

                         ret = NSS_STATUS_TRYAGAIN;

                         goto finalize;