From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Date: Sat, 12 Dec 2015 11:19:52 +0000 (+0200)
Subject: keys, trusted: fix: *do not* allow duplicate key options
X-Git-Tag: v4.5-rc1~70^2~7
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=5208cc83423dde06924121a85368c721a27ca555;p=linux.git

keys, trusted: fix: *do not* allow duplicate key options

The trusted keys option parsing allows specifying the same option
multiple times. The last option value specified is used.

This is problematic because:

* No gain.
* This makes complicated to specify options that are dependent on other
  options.

This patch changes the behavior in a way that option can be specified
only once.

Reported-by: James Morris James Morris <jmorris@namei.org>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
---

diff --git a/security/keys/trusted.c b/security/keys/trusted.c
index 903dace648a1..7c183c767a3a 100644
--- a/security/keys/trusted.c
+++ b/security/keys/trusted.c
@@ -736,11 +736,14 @@ static int getoptions(char *c, struct trusted_key_payload *pay,
 	int res;
 	unsigned long handle;
 	unsigned long lock;
+	unsigned long token_mask = 0;
 
 	while ((p = strsep(&c, " \t"))) {
 		if (*p == '\0' || *p == ' ' || *p == '\t')
 			continue;
 		token = match_token(p, key_tokens, args);
+		if (test_and_set_bit(token, &token_mask))
+			return -EINVAL;
 
 		switch (token) {
 		case Opt_pcrinfo: