From: nekral-guest <nekral-guest@5a98b0ae-9ef6-0310-add3-de5d479b70d7>
Date: Fri, 24 Apr 2009 23:23:51 +0000 (+0000)
Subject: 	* src/useradd.c: Check assumptions on snprintf().
X-Git-Tag: 4.1.4~89
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=1a87c698544de19a82e55d0fb5996090da8ae1d6;p=shadow

	* src/useradd.c: Check assumptions on snprintf().
	* src/useradd.c: Replace peror by an strerror and avoid an
	intermediate buffer.
	* src/useradd.c: Save errno between the failure and the report by
	perror/strerror.
	* src/useradd.c: Prefer xmalloc to malloc.
---

diff --git a/ChangeLog b/ChangeLog
index 11673e14..a7f73601 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2009-04-25  Nicolas François  <nicolas.francois@centraliens.net>
+
+	* src/useradd.c: Check assumptions on snprintf().
+	* src/useradd.c: Replace peror by an strerror and avoid an
+	intermediate buffer.
+	* src/useradd.c: Save errno between the failure and the report by
+	perror/strerror.
+	* src/useradd.c: Prefer xmalloc to malloc.
+
 2009-04-25  Nicolas François  <nicolas.francois@centraliens.net>
 
 	* src/lastlog.c: Remove function calls from within assert().
diff --git a/src/useradd.c b/src/useradd.c
index 261e9ca9..4757fd4d 100644
--- a/src/useradd.c
+++ b/src/useradd.c
@@ -48,6 +48,7 @@
 #endif				/* USE_PAM */
 #endif				/* ACCT_TOOLS_SETUID */
 #include <stdio.h>
+#include <string.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <time.h>
@@ -419,10 +420,11 @@ static int set_defaults (void)
 {
 	FILE *ifp;
 	FILE *ofp;
-	char buf[1024];
+	char buf[PATH_MAX];
 	static char new_file[] = NEW_USER_FILE;
 	char *cp;
 	int ofd;
+	int wlen;
 	bool out_group = false;
 	bool out_home = false;
 	bool out_inactive = false;
@@ -533,10 +535,13 @@ static int set_defaults (void)
 	/*
 	 * Rename the current default file to its backup name.
 	 */
-	snprintf (buf, sizeof buf, "%s-", def_file);
+	wlen = snprintf (buf, sizeof buf, "%s-", def_file);
+	assert (wlen < sizeof buf);
 	if ((rename (def_file, buf) != 0) && (ENOENT != errno)) {
-		snprintf (buf, sizeof buf, _("%s: rename: %s"), Prog, def_file);
-		perror (buf);
+		int err = errno;
+		fprintf (stderr,
+		         _("%s: rename: %s: %s"),
+		         Prog, def_file, strerror (err));
 		unlink (new_file);
 		return -1;
 	}
@@ -545,8 +550,10 @@ static int set_defaults (void)
 	 * Rename the new default file to its correct name.
 	 */
 	if (rename (new_file, def_file) != 0) {
-		snprintf (buf, sizeof buf, _("%s: rename: %s"), Prog, new_file);
-		perror (buf);
+		int err = errno;
+		fprintf (stderr,
+		         _("%s: rename: %s: %s"),
+		         Prog, new_file, strerror (err));
 		return -1;
 	}
 #ifdef WITH_AUDIT
@@ -1268,10 +1275,13 @@ static void process_flags (int argc, char **argv)
 		}
 		if (!dflg) {
 			char *uh;
+			size_t len = strlen (def_home) + strlen (user_name) + 2;
+			int wlen;
+
+			uh = xmalloc (len);
+			wlen = snprintf (uh, len, "%s/%s", def_home, user_name);
+			assert (wlen == (int) len -1);
 
-			uh = xmalloc (strlen (def_home) +
-			              strlen (user_name) + 2);
-			sprintf (uh, "%s/%s", def_home, user_name);
 			user_home = uh;
 		}
 	}
@@ -1841,7 +1851,7 @@ int main (int argc, char **argv)
 	OPENLOG ("useradd");
 
 	sys_ngroups = sysconf (_SC_NGROUPS_MAX);
-	user_groups = malloc ((1 + sys_ngroups) * sizeof (char *));
+	user_groups = xmalloc ((1 + sys_ngroups) * sizeof (char *));
 	/*
 	 * Initialize the list to be empty
 	 */