Correctly handle buffer overflow while reading line with fgets.

3 files changed, 61 insertions, 59 deletions

diff --git a/nis/nss_compat/compat-grp.c b/nis/nss_compat/compat-grp.c
index 91a19c0b77..693ade575e 100644
--- a/nis/nss_compat/compat-grp.c
+++ b/nis/nss_compat/compat-grp.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1996, 1997 Free Software Foundation, Inc.
+/* Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1996.
 
@@ -315,17 +315,15 @@ getgrent_next_file (struct group *result, ent_t *ent,
       do
 	{
 	  fgetpos (ent->stream, &pos);
+	  buffer[buflen - 1] = '\xff';
 	  p = fgets (buffer, buflen, ent->stream);
-	  if (p == NULL)
+	  if (p == NULL && feof (ent->stream))
+	    return NSS_STATUS_NOTFOUND;
+	  if (p == NULL || buffer[buflen - 1] != '\xff')
 	    {
-	      if (feof (ent->stream))
-		return NSS_STATUS_NOTFOUND;
-	      else
-		{
-		  fsetpos (ent->stream, &pos);
-		  __set_errno (ERANGE);
-		  return NSS_STATUS_TRYAGAIN;
-		}
+	      fsetpos (ent->stream, &pos);
+	      __set_errno (ERANGE);
+	      return NSS_STATUS_TRYAGAIN;
 	    }
 
 	  /* Terminate the line for any case.  */
@@ -446,17 +444,15 @@ internal_getgrnam_r (const char *name, struct group *result, ent_t *ent,
       do
 	{
 	  fgetpos (ent->stream, &pos);
+	  buffer[buflen - 1] = '\xff';
 	  p = fgets (buffer, buflen, ent->stream);
-	  if (p == NULL)
+	  if (p == NULL && feof (ent->stream))
+	    return NSS_STATUS_NOTFOUND;
+	  if (p == NULL || buffer[buflen - 1] != '\xff')
 	    {
-	      if (feof (ent->stream))
-		return NSS_STATUS_NOTFOUND;
-	      else
-		{
-		  fsetpos (ent->stream, &pos);
-		  __set_errno (ERANGE);
-		  return NSS_STATUS_TRYAGAIN;
-		}
+	      fsetpos (ent->stream, &pos);
+	      __set_errno (ERANGE);
+	      return NSS_STATUS_TRYAGAIN;
 	    }
 
 	  /* Terminate the line for any case.  */
@@ -607,17 +603,15 @@ internal_getgrgid_r (gid_t gid, struct group *result, ent_t *ent,
       do
 	{
 	  fgetpos (ent->stream, &pos);
+	  buffer[buflen - 1] = '\xff';
 	  p = fgets (buffer, buflen, ent->stream);
-	  if (p == NULL)
+	  if (p == NULL && feof (ent->stream))
+	    return NSS_STATUS_NOTFOUND;
+	  if (p == NULL || buffer[buflen - 1] != '\xff')
 	    {
-	      if (feof (ent->stream))
-		return NSS_STATUS_NOTFOUND;
-	      else
-		{
-		  fsetpos (ent->stream, &pos);
-		  __set_errno (ERANGE);
-		  return NSS_STATUS_TRYAGAIN;
-		}
+	      fsetpos (ent->stream, &pos);
+	      __set_errno (ERANGE);
+	      return NSS_STATUS_TRYAGAIN;
 	    }
 
 	  /* Terminate the line for any case.  */
diff --git a/nis/nss_compat/compat-pwd.c b/nis/nss_compat/compat-pwd.c
index afc35e2cfd..6b1712e5b7 100644
--- a/nis/nss_compat/compat-pwd.c
+++ b/nis/nss_compat/compat-pwd.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1996, 1997 Free Software Foundation, Inc.
+/* Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1996.
 
@@ -565,17 +565,15 @@ getpwent_next_file (struct passwd *result, ent_t *ent,
       do
 	{
 	  fgetpos (ent->stream, &pos);
+	  buffer[buflen - 1] = '\xff';
 	  p = fgets (buffer, buflen, ent->stream);
-	  if (p == NULL)
+	  if (p == NULL && feof (ent->stream))
+	    return NSS_STATUS_NOTFOUND;
+	  if (p == NULL || buffer[buflen - 1] != '\xff')
 	    {
-	      if (feof (ent->stream))
-		return NSS_STATUS_NOTFOUND;
- 	      else
- 		{
-		  fsetpos (ent->stream, &pos);
- 		  __set_errno (ERANGE);
- 		  return NSS_STATUS_TRYAGAIN;
- 		}
+	      fsetpos (ent->stream, &pos);
+	      __set_errno (ERANGE);
+	      return NSS_STATUS_TRYAGAIN;
  	    }
 
 	  /* Terminate the line for any case.  */
@@ -745,17 +743,15 @@ internal_getpwnam_r (const char *name, struct passwd *result, ent_t *ent,
       do
 	{
 	  fgetpos (ent->stream, &pos);
+	  buffer[buflen - 1] = '\xff';
 	  p = fgets (buffer, buflen, ent->stream);
-	  if (p == NULL)
+	  if (p == NULL && feof (ent->stream))
+	    return NSS_STATUS_NOTFOUND;
+	  if (p == NULL || buffer[buflen - 1] != '\xff')
 	    {
-	      if (feof (ent->stream))
-		return NSS_STATUS_NOTFOUND;
-	      else
-		{
-		  fsetpos (ent->stream, &pos);
-		  __set_errno (ERANGE);
-		  return NSS_STATUS_TRYAGAIN;
-		}
+	      fsetpos (ent->stream, &pos);
+	      __set_errno (ERANGE);
+	      return NSS_STATUS_TRYAGAIN;
 	    }
 
 	  /* Terminate the line for any case.  */
@@ -982,17 +978,15 @@ internal_getpwuid_r (uid_t uid, struct passwd *result, ent_t *ent,
       do
 	{
 	  fgetpos (ent->stream, &pos);
+	  buffer[buflen - 1] = '\xff';
 	  p = fgets (buffer, buflen, ent->stream);
-	  if (p == NULL)
+	  if (p == NULL && feof (ent->stream))
+	    return NSS_STATUS_NOTFOUND;
+	  if (p == NULL || buffer[buflen - 1] != '\xff')
 	    {
-	      if (feof (ent->stream))
-		return NSS_STATUS_NOTFOUND;
-	      else
-		{
-		  fsetpos (ent->stream, &pos);
-		  __set_errno (ERANGE);
-		  return NSS_STATUS_TRYAGAIN;
-		}
+	      fsetpos (ent->stream, &pos);
+	      __set_errno (ERANGE);
+	      return NSS_STATUS_TRYAGAIN;
 	    }
 
 	  /* Terminate the line for any case.  */
diff --git a/nis/nss_compat/compat-spwd.c b/nis/nss_compat/compat-spwd.c
index 76ce8831e7..007305c424 100644
--- a/nis/nss_compat/compat-spwd.c
+++ b/nis/nss_compat/compat-spwd.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1996, 1997 Free Software Foundation, Inc.
+/* Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1996.
 
@@ -515,9 +515,16 @@ getspent_next_file (struct spwd *result, ent_t *ent,
       do
 	{
 	  fgetpos (ent->stream, &pos);
+	  buffer[buflen - 1] = '\xff';
 	  p = fgets (buffer, buflen, ent->stream);
-	  if (p == NULL)
+	  if (p == NULL && feof (ent->stream))
 	    return NSS_STATUS_NOTFOUND;
+	  if (p == NULL || buffer[buflen - 1] != '\xff')
+	    {
+	      fsetpos (ent->stream, &pos);
+	      __set_errno (ERANGE);
+	      return NSS_STATUS_TRYAGAIN;
+	    }
 
 	  /* Terminate the line for any case.  */
 	  buffer[buflen - 1] = '\0';
@@ -690,9 +697,16 @@ internal_getspnam_r (const char *name, struct spwd *result, ent_t *ent,
       do
 	{
 	  fgetpos (ent->stream, &pos);
+	  buffer[buflen - 1] = '\xff';
 	  p = fgets (buffer, buflen, ent->stream);
-	  if (p == NULL)
+	  if (p == NULL && feof (ent->stream))
 	    return NSS_STATUS_NOTFOUND;
+	  if (p == NULL || buffer[buflen - 1] != '\xff')
+	    {
+	      fsetpos (ent->stream, &pos);
+	      __set_errno (ERANGE);
+	      return NSS_STATUS_TRYAGAIN;
+	    }
 
 	  /* Terminate the line for any case.  */
 	  buffer[buflen - 1] = '\0';