diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index 635e5c1e3e48..5de18a6d5c3f 100644
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -838,6 +838,7 @@ int __init avc_add_callback(int (*callback)(u32 event), u32 events)
  * @ssid,@tsid,@tclass : identifier of an AVC entry
  * @seqno : sequence number when decision was made
  * @xpd: extended_perms_decision to be added to the node
+ * @flags: the AVC_* flags, e.g. AVC_NONBLOCKING, AVC_EXTENDED_PERMS, or 0.
  *
  * if a valid AVC entry doesn't exist,this function returns -ENOENT.
  * if kmalloc() called internal returns NULL, this function returns -ENOMEM.
@@ -856,6 +857,23 @@ static int avc_update_node(struct selinux_avc *avc,
 	struct hlist_head *head;
 	spinlock_t *lock;
 
+	/*
+	 * If we are in a non-blocking code path, e.g. VFS RCU walk,
+	 * then we must not add permissions to a cache entry
+	 * because we cannot safely audit the denial.  Otherwise,
+	 * during the subsequent blocking retry (e.g. VFS ref walk), we
+	 * will find the permissions already granted in the cache entry
+	 * and won't audit anything at all, leading to silent denials in
+	 * permissive mode that only appear when in enforcing mode.
+	 *
+	 * See the corresponding handling in slow_avc_audit(), and the
+	 * logic in selinux_inode_follow_link and selinux_inode_permission
+	 * for the VFS MAY_NOT_BLOCK flag, which is transliterated into
+	 * AVC_NONBLOCKING for avc_has_perm_noaudit().
+	 */
+	if (flags & AVC_NONBLOCKING)
+		return 0;
+
 	node = avc_alloc_node(avc);
 	if (!node) {
 		rc = -ENOMEM;
@@ -1115,7 +1133,7 @@ int avc_has_extended_perms(struct selinux_state *state,
  * @tsid: target security identifier
  * @tclass: target security class
  * @requested: requested permissions, interpreted based on @tclass
- * @flags:  AVC_STRICT or 0
+ * @flags:  AVC_STRICT, AVC_NONBLOCKING, or 0
  * @avd: access vector decisions
  *
  * Check the AVC to determine whether the @requested permissions are granted
@@ -1199,7 +1217,8 @@ int avc_has_perm_flags(struct selinux_state *state,
 	struct av_decision avd;
 	int rc, rc2;
 
-	rc = avc_has_perm_noaudit(state, ssid, tsid, tclass, requested, 0,
+	rc = avc_has_perm_noaudit(state, ssid, tsid, tclass, requested,
+				  (flags & MAY_NOT_BLOCK) ? AVC_NONBLOCKING : 0,
 				  &avd);
 
 	rc2 = avc_audit(state, ssid, tsid, tclass, requested, &avd, rc,
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index f0e36c3492ba..7f6068489a02 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2982,7 +2982,9 @@ static int selinux_inode_permission(struct inode *inode, int mask)
 		return PTR_ERR(isec);
 
 	rc = avc_has_perm_noaudit(&selinux_state,
-				  sid, isec->sid, isec->sclass, perms, 0, &avd);
+				  sid, isec->sid, isec->sclass, perms,
+				  (flags & MAY_NOT_BLOCK) ? AVC_NONBLOCKING : 0,
+				  &avd);
 	audited = avc_audit_required(perms, &avd, rc,
 				     from_access ? FILE__AUDIT_ACCESS : 0,
 				     &denied);
diff --git a/security/selinux/include/avc.h b/security/selinux/include/avc.h
index ef899bcfd2cb..74ea50977c20 100644
--- a/security/selinux/include/avc.h
+++ b/security/selinux/include/avc.h
@@ -142,6 +142,7 @@ static inline int avc_audit(struct selinux_state *state,
 
 #define AVC_STRICT 1 /* Ignore permissive mode. */
 #define AVC_EXTENDED_PERMS 2	/* update extended permissions */
+#define AVC_NONBLOCKING    4	/* non blocking */
 int avc_has_perm_noaudit(struct selinux_state *state,
 			 u32 ssid, u32 tsid,
 			 u16 tclass, u32 requested,