smack: fix: allow either entry be missing on access/access2 check (v2)
This is a regression caused by f7112e6c. When either subject or
object is not found the answer for access should be no. This
patch fixes the situation. '0' is written back instead of failing
with -EINVAL.
v2: cosmetic style fixes
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c
index 160aa08e..1c89ade 100644
--- a/security/smack/smackfs.c
+++ b/security/smack/smackfs.c
@@ -301,7 +301,8 @@
* @import: if non-zero, import labels
* @len: label length limit
*
- * Returns 0 on success, -1 on failure
+ * Returns 0 on success, -EINVAL on failure and -ENOENT when either subject
+ * or object is missing.
*/
static int smk_fill_rule(const char *subject, const char *object,
const char *access1, const char *access2,
@@ -314,28 +315,28 @@
if (import) {
rule->smk_subject = smk_import_entry(subject, len);
if (rule->smk_subject == NULL)
- return -1;
+ return -EINVAL;
rule->smk_object = smk_import(object, len);
if (rule->smk_object == NULL)
- return -1;
+ return -EINVAL;
} else {
cp = smk_parse_smack(subject, len);
if (cp == NULL)
- return -1;
+ return -EINVAL;
skp = smk_find_entry(cp);
kfree(cp);
if (skp == NULL)
- return -1;
+ return -ENOENT;
rule->smk_subject = skp;
cp = smk_parse_smack(object, len);
if (cp == NULL)
- return -1;
+ return -EINVAL;
skp = smk_find_entry(cp);
kfree(cp);
if (skp == NULL)
- return -1;
+ return -ENOENT;
rule->smk_object = skp->smk_known;
}
@@ -381,6 +382,7 @@
{
ssize_t cnt = 0;
char *tok[4];
+ int rc;
int i;
/*
@@ -405,10 +407,8 @@
while (i < 4)
tok[i++] = NULL;
- if (smk_fill_rule(tok[0], tok[1], tok[2], tok[3], rule, import, 0))
- return -1;
-
- return cnt;
+ rc = smk_fill_rule(tok[0], tok[1], tok[2], tok[3], rule, import, 0);
+ return rc == 0 ? cnt : rc;
}
#define SMK_FIXED24_FMT 0 /* Fixed 24byte label format */
@@ -1856,11 +1856,12 @@
res = smk_parse_long_rule(data, &rule, 0, 3);
}
- if (res < 0)
+ if (res >= 0)
+ res = smk_access(rule.smk_subject, rule.smk_object,
+ rule.smk_access1, NULL);
+ else if (res != -ENOENT)
return -EINVAL;
- res = smk_access(rule.smk_subject, rule.smk_object,
- rule.smk_access1, NULL);
data[0] = res == 0 ? '1' : '0';
data[1] = '\0';