Merge branch 'next-smack' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

Pull smack updates from James Morris:
 "Two Smack patches for 4.21.

  Jose's patch adds missing documentation and Zoran's fleshes out the
  access checks on keyrings"

* 'next-smack' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  Smack: Improve Documentation
  smack: fix access permissions for keyring

1 files changed, 9 insertions, 3 deletions

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 81fb4c1631e9..cd720c06b78c 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -4333,6 +4333,12 @@ static int smack_key_permission(key_ref_t key_ref,
         int request = 0;
         int rc;
 
+        /*
+         * Validate requested permissions
+         */
+        if (perm & ~KEY_NEED_ALL)
+                return -EINVAL;
+
         keyp = key_ref_to_ptr(key_ref);
         if (keyp == NULL)
                 return -EINVAL;
@@ -4356,10 +4362,10 @@ static int smack_key_permission(key_ref_t key_ref,
         ad.a.u.key_struct.key = keyp->serial;
         ad.a.u.key_struct.key_desc = keyp->description;
 #endif
-        if (perm & KEY_NEED_READ)
-                request = MAY_READ;
+        if (perm & (KEY_NEED_READ | KEY_NEED_SEARCH | KEY_NEED_VIEW))
+                request |= MAY_READ;
         if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR))
-                request = MAY_WRITE;
+                request |= MAY_WRITE;
         rc = smk_access(tkp, keyp->security, request, &ad);
         rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
         return rc;