cifs-utils/0005-cifscreds-better-error-handling-for-key_add.patch

From 382ec63757c1d8d4d399d17ccc927c4897d4cfc9 Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@samba.org>
Date: Sun, 20 Apr 2014 20:41:05 -0400
Subject: [PATCH] cifscreds: better error handling for key_add

If the string buffers would have been overrun, set errno to EINVAL
before returning. Then, have the callers report the errors to
stderr or syslog as appropriate.

Cc: Sebastian Krahmer <krahmer@suse.de>
Signed-off-by: Jeff Layton <jlayton@samba.org>
---
 cifscreds.c     | 6 +++---
 cifskey.c       | 8 ++++++--
 pam_cifscreds.c | 9 +++++----
 3 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/cifscreds.c b/cifscreds.c
index 64d55b0..5d84c3c 100644
--- a/cifscreds.c
+++ b/cifscreds.c
@@ -220,8 +220,8 @@ static int cifscreds_add(struct cmdarg *arg)
 	while (currentaddress) {
 		key_serial_t key = key_add(currentaddress, arg->user, pass, arg->keytype);
 		if (key <= 0) {
-			fprintf(stderr, "error: Add credential key for %s\n",
-				currentaddress);
+			fprintf(stderr, "error: Add credential key for %s: %s\n",
+				currentaddress, strerror(errno));
 		} else {
 			if (keyctl(KEYCTL_SETPERM, key, CIFS_KEY_PERMS) < 0) {
 				fprintf(stderr, "error: Setting permissons "
@@ -422,7 +422,7 @@ static int cifscreds_update(struct cmdarg *arg)
 		key_serial_t key = key_add(addrs[id], arg->user, pass, arg->keytype);
 		if (key <= 0)
 			fprintf(stderr, "error: Update credential key "
-				"for %s\n", addrs[id]);
+				"for %s: %s\n", addrs[id], strerror(errno));
 	}
 
 	return EXIT_SUCCESS;
diff --git a/cifskey.c b/cifskey.c
index 4f01ed0..919540f 100644
--- a/cifskey.c
+++ b/cifskey.c
@@ -47,13 +47,17 @@ key_add(const char *addr, const char *user, const char *pass, char keytype)
 	char val[MOUNT_PASSWD_SIZE +  MAX_USERNAME_SIZE + 2];
 
 	/* set key description */
-	if (snprintf(desc, sizeof(desc), "%s:%c:%s", KEY_PREFIX, keytype, addr) >= (int)sizeof(desc))
+	if (snprintf(desc, sizeof(desc), "%s:%c:%s", KEY_PREFIX, keytype, addr) >= (int)sizeof(desc)) {
+		errno = EINVAL;
 		return -1;
+	}
 
 	/* set payload contents */
 	len = snprintf(val, sizeof(val), "%s:%s", user, pass);
-	if (len >= (int)sizeof(val))
+	if (len >= (int)sizeof(val)) {
+		errno = EINVAL;
 		return -1;
+	}
 
 	return add_key(CIFS_KEY_TYPE, desc, val, len + 1, DEST_KEYRING);
 }
diff --git a/pam_cifscreds.c b/pam_cifscreds.c
index fb23117..5d99c2d 100644
--- a/pam_cifscreds.c
+++ b/pam_cifscreds.c
@@ -208,6 +208,7 @@ static int cifscreds_pam_add(pam_handle_t *ph, const char *user, const char *pas
 
 		switch(errno) {
 		case ENOKEY:
+			/* success */
 			break;
 		default:
 			pam_syslog(ph, LOG_ERR, "Unable to search keyring for %s (%s)",
@@ -233,8 +234,8 @@ static int cifscreds_pam_add(pam_handle_t *ph, const char *user, const char *pas
 	while (currentaddress) {
 		key_serial_t key = key_add(currentaddress, user, password, keytype);
 		if (key <= 0) {
-			pam_syslog(ph, LOG_ERR, "error: Add credential key for %s",
-				currentaddress);
+			pam_syslog(ph, LOG_ERR, "error: Add credential key for %s: %s",
+				currentaddress, strerror(errno));
 		} else {
 			if ((args & ARG_DEBUG) == ARG_DEBUG) {
 				pam_syslog(ph, LOG_DEBUG, "credential key for \\\\%s\\%s added",
@@ -336,8 +337,8 @@ static int cifscreds_pam_update(pam_handle_t *ph, const char *user, const char *
 	for (id = 0; id < count; id++) {
 		key_serial_t key = key_add(currentaddress, user, password, keytype);
 		if (key <= 0) {
-			pam_syslog(ph, LOG_ERR, "error: Update credential key for %s",
-				currentaddress);
+			pam_syslog(ph, LOG_ERR, "error: Update credential key for %s: %s",
+				currentaddress, strerror(errno));
 		}
 	}
 
-- 
1.8.4.2