Commit 3b9fc372 authored Jul 26, 2012 by Alan Cox Committed by James Morris Jul 30, 2012

smack: off by one error



Consider the input case of a rule that consists entirely of non space
symbols followed by a \0. Say 64 + \0

In this case strlen(data) = 64
kzalloc of subject and object are 64 byte objects
sscanfdata, "%s %s %s", subject, ...)

will put 65 bytes into subject.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>

parent f7da9cdf

security/smack/smackfs.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -323,11 +323,11 @@ static int smk_parse_long_rule(const char data, struct smack_rule rule,
		int datalen;
		int rc = -1;

		/*
		* This is probably inefficient, but safe.
		*/
		/* This is inefficient */
		datalen = strlen(data);
		subject = kzalloc(datalen, GFP_KERNEL);

		/* Our first element can be 64 + \0 with no spaces */
		subject = kzalloc(datalen + 1, GFP_KERNEL);
		if (subject == NULL)
		return -1;
		object = kzalloc(datalen, GFP_KERNEL);