svn commit: r336619 - head/lib/libc/gen

[Ian Lepore]

Author: ian
Date: Sun Jul 22 22:34:20 2018
New Revision: 336619
URL: https://svnweb.freebsd.org/changeset/base/336619

Log:
  Set the pw_class field to NULL when scanning the non-master passwd file.
  This avoids a null pointer deref in pw_dup(), which assumes that all
  pointers are either NULL or valid.

Modified:
  head/lib/libc/gen/pw_scan.c

Modified: head/lib/libc/gen/pw_scan.c
==============================================================================
--- head/lib/libc/gen/pw_scan.c	Sun Jul 22 21:39:27 2018	(r336618)
+++ head/lib/libc/gen/pw_scan.c	Sun Jul 22 22:34:20 2018	(r336619)
@@ -170,7 +170,8 @@ __pw_scan(char *bp, struct passwd *pw, int flags)
 		if (p[0])
 			pw->pw_fields |= _PWF_EXPIRE;
 		pw->pw_expire = atol(p);
-	}
+	} else
+		pw->pw_class = NULL;
 	if (!(pw->pw_gecos = strsep(&bp, ":")))		/* gecos */
 		goto fmt;
 	if (pw->pw_gecos[0])