commit 89f187a40fc0ad4e22838526bfe34d73f758b776

Author: Florian Weimer <fweimer@redhat.com>

Date:   Fri Jun 16 20:54:43 2017 +0200

    resolv: Use getline for configuration file reading in res_vinit_1

diff --git a/resolv/res_init.c b/resolv/res_init.c

index e604a0212fa13624..ed5a4d4804a792de 100644

--- a/resolv/res_init.c

+++ b/resolv/res_init.c

@@ -126,10 +126,10 @@ is_sort_mask (char ch)

    deallocation and error handling.  Return true on success, false on

    failure.  */

 static bool

-res_vinit_1 (res_state statp, bool preinit, FILE *fp)

+res_vinit_1 (res_state statp, bool preinit, FILE *fp, char **buffer)

 {

   char *cp, **pp;

-  char buf[BUFSIZ];

+  size_t buffer_size = 0;

   int nserv = 0;    /* Number of nameservers read from file.  */

   bool have_serv6 = false;

   bool haveenv = false;

@@ -197,27 +197,38 @@ res_vinit_1 (res_state statp, bool preinit, FILE *fp)

     }

 #define MATCH(line, name)                       \

-  (!strncmp (line, name, sizeof (name) - 1)     \

-   && (line[sizeof (name) - 1] == ' '           \

-       || line[sizeof (name) - 1] == '\t'))

+  (!strncmp ((line), name, sizeof (name) - 1)     \

+   && ((line)[sizeof (name) - 1] == ' '           \

+       || (line)[sizeof (name) - 1] == '\t'))

   if (fp != NULL)

     {

       /* No threads use this stream.  */

       __fsetlocking (fp, FSETLOCKING_BYCALLER);

       /* Read the config file.  */

-      while (__fgets_unlocked (buf, sizeof (buf), fp) != NULL)

+      while (true)

         {

+          {

+            ssize_t ret = __getline (buffer, &buffer_size, fp);

+            if (ret <= 0)

+              {

+                if (_IO_ferror_unlocked (fp))

+                  return false;

+                else

+                  break;

+              }

+          }

+

           /* Skip comments.  */

-          if (*buf == ';' || *buf == '#')

+          if (**buffer == ';' || **buffer == '#')

             continue;

           /* Read default domain name.  */

-          if (MATCH (buf, "domain"))

+          if (MATCH (*buffer, "domain"))

             {

               if (haveenv)

                 /* LOCALDOMAIN overrides the configuration file.  */

                 continue;

-              cp = buf + sizeof ("domain") - 1;

+              cp = *buffer + sizeof ("domain") - 1;

               while (*cp == ' ' || *cp == '\t')

                 cp++;

               if ((*cp == '\0') || (*cp == '\n'))

@@ -230,12 +241,12 @@ res_vinit_1 (res_state statp, bool preinit, FILE *fp)

               continue;

             }

           /* Set search list.  */

-          if (MATCH (buf, "search"))

+          if (MATCH (*buffer, "search"))

             {

               if (haveenv)

                 /* LOCALDOMAIN overrides the configuration file.  */

                 continue;

-              cp = buf + sizeof ("search") - 1;

+              cp = *buffer + sizeof ("search") - 1;

               while (*cp == ' ' || *cp == '\t')

                 cp++;

               if ((*cp == '\0') || (*cp == '\n'))

@@ -271,11 +282,11 @@ res_vinit_1 (res_state statp, bool preinit, FILE *fp)

               continue;

             }

           /* Read nameservers to query.  */

-          if (MATCH (buf, "nameserver") && nserv < MAXNS)

+          if (MATCH (*buffer, "nameserver") && nserv < MAXNS)

             {

               struct in_addr a;

-              cp = buf + sizeof ("nameserver") - 1;

+              cp = *buffer + sizeof ("nameserver") - 1;

               while (*cp == ' ' || *cp == '\t')

                 cp++;

               if ((*cp != '\0') && (*cp != '\n') && __inet_aton (cp, &a))

@@ -300,7 +311,7 @@ res_vinit_1 (res_state statp, bool preinit, FILE *fp)

                       sa6 = malloc (sizeof (*sa6));

                       if (sa6 == NULL)

-                        return -1;

+                        return false;

                       sa6->sin6_family = AF_INET6;

                       sa6->sin6_port = htons (NAMESERVER_PORT);

@@ -323,11 +334,11 @@ res_vinit_1 (res_state statp, bool preinit, FILE *fp)

                 }

               continue;

             }

-          if (MATCH (buf, "sortlist"))

+          if (MATCH (*buffer, "sortlist"))

             {

               struct in_addr a;

-              cp = buf + sizeof ("sortlist") - 1;

+              cp = *buffer + sizeof ("sortlist") - 1;

               while (nsort < MAXRESOLVSORT)

                 {

                   while (*cp == ' ' || *cp == '\t')

@@ -367,9 +378,9 @@ res_vinit_1 (res_state statp, bool preinit, FILE *fp)

                 }

               continue;

             }

-          if (MATCH (buf, "options"))

+          if (MATCH (*buffer, "options"))

             {

-              res_setoptions (statp, buf + sizeof ("options") - 1, "conf");

+              res_setoptions (statp, *buffer + sizeof ("options") - 1, "conf");

               continue;

             }

         }

@@ -387,10 +398,13 @@ res_vinit_1 (res_state statp, bool preinit, FILE *fp)

       statp->nsaddr.sin_port = htons (NAMESERVER_PORT);

       statp->nscount = 1;

     }

-  if (statp->defdname[0] == 0

-      && __gethostname (buf, sizeof (statp->defdname) - 1) == 0

-      && (cp = strchr (buf, '.')) != NULL)

-    strcpy (statp->defdname, cp + 1);

+  if (statp->defdname[0] == 0)

+    {

+      char buf[sizeof (statp->defdname)];

+      if (__gethostname (buf, sizeof (statp->defdname) - 1) == 0

+          && (cp = strchr (buf, '.')) != NULL)

+        strcpy (statp->defdname, cp + 1);

+    }

   /* Find components of local domain that might be searched.  */

   if (!havesearch)

@@ -404,7 +418,7 @@ res_vinit_1 (res_state statp, bool preinit, FILE *fp)

   if ((cp = getenv ("RES_OPTIONS")) != NULL)

     res_setoptions (statp, cp, "env");

   statp->options |= RES_INIT;

-  return 0;

+  return true;

 }

 /* Set up default settings.  If the /etc/resolv.conf configuration

@@ -434,7 +448,12 @@ __res_vinit (res_state statp, int preinit)

            need to be handled by the application.  */

         return -1;

       }

-  if (!res_vinit_1 (statp, preinit, fp))

+

+  char *buffer = NULL;

+  bool ok = res_vinit_1 (statp, preinit, fp, &buffer);

+  free (buffer);

+

+  if (!ok)

     {

       /* Deallocate the name server addresses which have been

          allocated.  */