LSM: Make the Labeled IPsec hooks more stack friendly

The xfrm_get_policy() and xfrm_add_pol_expire() put some rather large structs
on the stack to work around the LSM API.  This patch attempts to fix that
problem by changing the LSM API to require only the relevant "security"
pointers instead of the entire SPD entry; we do this for all of the
security_xfrm_policy*() functions to keep things consistent.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 24 insertions, 24 deletions

diff --git a/include/linux/security.h b/include/linux/security.h
index c673dfd4dff..f5eb9ff47ac 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -910,24 +910,24 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
  * Security hooks for XFRM operations.
  *
  * @xfrm_policy_alloc_security:
- *	@xp contains the xfrm_policy being added to Security Policy Database
- *	used by the XFRM system.
+ *	@ctxp is a pointer to the xfrm_sec_ctx being added to Security Policy
+ *	Database used by the XFRM system.
  *	@sec_ctx contains the security context information being provided by
  *	the user-level policy update program (e.g., setkey).
  *	Allocate a security structure to the xp->security field; the security
  *	field is initialized to NULL when the xfrm_policy is allocated.
  *	Return 0 if operation was successful (memory to allocate, legal context)
  * @xfrm_policy_clone_security:
- *	@old contains an existing xfrm_policy in the SPD.
- *	@new contains a new xfrm_policy being cloned from old.
- *	Allocate a security structure to the new->security field
- *	that contains the information from the old->security field.
+ *	@old_ctx contains an existing xfrm_sec_ctx.
+ *	@new_ctxp contains a new xfrm_sec_ctx being cloned from old.
+ *	Allocate a security structure in new_ctxp that contains the
+ *	information from the old_ctx structure.
  *	Return 0 if operation was successful (memory to allocate).
  * @xfrm_policy_free_security:
- *	@xp contains the xfrm_policy
+ *	@ctx contains the xfrm_sec_ctx
  *	Deallocate xp->security.
  * @xfrm_policy_delete_security:
- *	@xp contains the xfrm_policy.
+ *	@ctx contains the xfrm_sec_ctx.
  *	Authorize deletion of xp->security.
  * @xfrm_state_alloc_security:
  *	@x contains the xfrm_state being added to the Security Association
@@ -947,7 +947,7 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
  *	@x contains the xfrm_state.
  *	Authorize deletion of x->security.
  * @xfrm_policy_lookup:
- *	@xp contains the xfrm_policy for which the access control is being
+ *	@ctx contains the xfrm_sec_ctx for which the access control is being
  *	checked.
  *	@fl_secid contains the flow security label that is used to authorize
  *	access to the policy xp.
@@ -1454,17 +1454,17 @@ struct security_operations {
 #endif	/* CONFIG_SECURITY_NETWORK */
 
 #ifdef CONFIG_SECURITY_NETWORK_XFRM
-	int (*xfrm_policy_alloc_security) (struct xfrm_policy *xp,
+	int (*xfrm_policy_alloc_security) (struct xfrm_sec_ctx **ctxp,
 			struct xfrm_user_sec_ctx *sec_ctx);
-	int (*xfrm_policy_clone_security) (struct xfrm_policy *old, struct xfrm_policy *new);
-	void (*xfrm_policy_free_security) (struct xfrm_policy *xp);
-	int (*xfrm_policy_delete_security) (struct xfrm_policy *xp);
+	int (*xfrm_policy_clone_security) (struct xfrm_sec_ctx *old_ctx, struct xfrm_sec_ctx **new_ctx);
+	void (*xfrm_policy_free_security) (struct xfrm_sec_ctx *ctx);
+	int (*xfrm_policy_delete_security) (struct xfrm_sec_ctx *ctx);
 	int (*xfrm_state_alloc_security) (struct xfrm_state *x,
 		struct xfrm_user_sec_ctx *sec_ctx,
 		u32 secid);
 	void (*xfrm_state_free_security) (struct xfrm_state *x);
 	int (*xfrm_state_delete_security) (struct xfrm_state *x);
-	int (*xfrm_policy_lookup)(struct xfrm_policy *xp, u32 fl_secid, u8 dir);
+	int (*xfrm_policy_lookup)(struct xfrm_sec_ctx *ctx, u32 fl_secid, u8 dir);
 	int (*xfrm_state_pol_flow_match)(struct xfrm_state *x,
 			struct xfrm_policy *xp, struct flowi *fl);
 	int (*xfrm_decode_session)(struct sk_buff *skb, u32 *secid, int ckall);
@@ -2562,16 +2562,16 @@ static inline void security_inet_conn_established(struct sock *sk,
 
 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 
-int security_xfrm_policy_alloc(struct xfrm_policy *xp, struct xfrm_user_sec_ctx *sec_ctx);
-int security_xfrm_policy_clone(struct xfrm_policy *old, struct xfrm_policy *new);
-void security_xfrm_policy_free(struct xfrm_policy *xp);
-int security_xfrm_policy_delete(struct xfrm_policy *xp);
+int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp, struct xfrm_user_sec_ctx *sec_ctx);
+int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx, struct xfrm_sec_ctx **new_ctxp);
+void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx);
+int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx);
 int security_xfrm_state_alloc(struct xfrm_state *x, struct xfrm_user_sec_ctx *sec_ctx);
 int security_xfrm_state_alloc_acquire(struct xfrm_state *x,
 				      struct xfrm_sec_ctx *polsec, u32 secid);
 int security_xfrm_state_delete(struct xfrm_state *x);
 void security_xfrm_state_free(struct xfrm_state *x);
-int security_xfrm_policy_lookup(struct xfrm_policy *xp, u32 fl_secid, u8 dir);
+int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid, u8 dir);
 int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
 				       struct xfrm_policy *xp, struct flowi *fl);
 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid);
@@ -2579,21 +2579,21 @@ void security_skb_classify_flow(struct sk_buff *skb, struct flowi *fl);
 
 #else	/* CONFIG_SECURITY_NETWORK_XFRM */
 
-static inline int security_xfrm_policy_alloc(struct xfrm_policy *xp, struct xfrm_user_sec_ctx *sec_ctx)
+static inline int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp, struct xfrm_user_sec_ctx *sec_ctx)
 {
 	return 0;
 }
 
-static inline int security_xfrm_policy_clone(struct xfrm_policy *old, struct xfrm_policy *new)
+static inline int security_xfrm_policy_clone(struct xfrm_sec_ctx *old, struct xfrm_sec_ctx **new_ctxp)
 {
 	return 0;
 }
 
-static inline void security_xfrm_policy_free(struct xfrm_policy *xp)
+static inline void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx)
 {
 }
 
-static inline int security_xfrm_policy_delete(struct xfrm_policy *xp)
+static inline int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx)
 {
 	return 0;
 }
@@ -2619,7 +2619,7 @@ static inline int security_xfrm_state_delete(struct xfrm_state *x)
 	return 0;
 }
 
-static inline int security_xfrm_policy_lookup(struct xfrm_policy *xp, u32 fl_secid, u8 dir)
+static inline int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid, u8 dir)
 {
 	return 0;
 }