[linux-cifs-client] [RFC/PATCH: 2/2]: CIFS: Add kernel warning if password length exceeds limit

[Suresh Jayaraman]

Add a kernel warning if password length exceeds 16 bytes in case of
"sec=lanman". Also, add password length check as Windows passwords
are limited to 127 bytes.

Signed-off-by: Suresh Jayaraman <sjayaraman at suse.de>
---

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index fd9147c..c6dd91f 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -880,10 +880,11 @@ cifs_parse_mount_options(char *options, const char *devname,
 					vol->password = NULL;
 					continue;
 				}
+			} else if (strnlen(value, 128) >= 128) {
+				printk(KERN_WARNING "CIFS: password too long\n");
+				return 1;
 			}
 			temp_len = strlen(value);
-			/* removed password length check, NTLM passwords
-				can be arbitrarily long */
 
 			/* if comma in password, the string will be
 			prematurely null terminated.  Commas in password are
@@ -988,6 +989,11 @@ cifs_parse_mount_options(char *options, const char *devname,
 				vol->secFlg |= CIFSSEC_MAY_NTLMV2;
 #ifdef CONFIG_CIFS_WEAK_PW_HASH
 			} else if (strnicmp(value, "lanman", 6) == 0) {
+				if (strnlen(vol->password, 17) >= 17) {
+					printk(KERN_WARNING "CIFS: password too"
+					       "long for lanman sec mode\n");
+					return 1;
+				}
 				vol->secFlg |= CIFSSEC_MAY_LANMAN;
 #endif
 			} else if (strnicmp(value, "none", 4) == 0) {