Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

Pull security subsystem updates from James Morris:
 "In this patchset, we finally get an SELinux update, with Paul Moore
  taking over as maintainer of that code.

  Also a significant update for the Keys subsystem, as well as
  maintenance updates to Smack, IMA, TPM, and Apparmor"

and since I wanted to know more about the updates to key handling,
here's the explanation from David Howells on that:

 "Okay.  There are a number of separate bits.  I'll go over the big bits
  and the odd important other bit, most of the smaller bits are just
  fixes and cleanups.  If you want the small bits accounting for, I can
  do that too.

   (1) Keyring capacity expansion.

        KEYS: Consolidate the concept of an 'index key' for key access
        KEYS: Introduce a search context structure
        KEYS: Search for auth-key by name rather than target key ID
        Add a generic associative array implementation.
        KEYS: Expand the capacity of a keyring

     Several of the patches are providing an expansion of the capacity of a
     keyring.  Currently, the maximum size of a keyring payload is one page.
     Subtract a small header and then divide up into pointers, that only gives
     you ~500 pointers on an x86_64 box.  However, since the NFS idmapper uses
     a keyring to store ID mapping data, that has proven to be insufficient to
     the cause.

     Whatever data structure I use to handle the keyring payload, it can only
     store pointers to keys, not the keys themselves because several keyrings
     may point to a single key.  This precludes inserting, say, and rb_node
     struct into the key struct for this purpose.

     I could make an rbtree of records such that each record has an rb_node
     and a key pointer, but that would use four words of space per key stored
     in the keyring.  It would, however, be able to use much existing code.

     I selected instead a non-rebalancing radix-tree type approach as that
     could have a better space-used/key-pointer ratio.  I could have used the
     radix tree implementation that we already have and insert keys into it by
     their serial numbers, but that means any sort of search must iterate over
     the whole radix tree.  Further, its nodes are a bit on the capacious side
     for what I want - especially given that key serial numbers are randomly
     allocated, thus leaving a lot of empty space in the tree.

     So what I have is an associative array that internally is a radix-tree
     with 16 pointers per node where the index key is constructed from the key
     type pointer and the key description.  This means that an exact lookup by
     type+description is very fast as this tells us how to navigate directly to
     the target key.

     I made the data structure general in lib/assoc_array.c as far as it is
     concerned, its index key is just a sequence of bits that leads to a
     pointer.  It's possible that someone else will be able to make use of it
     also.  FS-Cache might, for example.

   (2) Mark keys as 'trusted' and keyrings as 'trusted only'.

        KEYS: verify a certificate is signed by a 'trusted' key
        KEYS: Make the system 'trusted' keyring viewable by userspace
        KEYS: Add a 'trusted' flag and a 'trusted only' flag
        KEYS: Separate the kernel signature checking keyring from module signing

     These patches allow keys carrying asymmetric public keys to be marked as
     being 'trusted' and allow keyrings to be marked as only permitting the
     addition or linkage of trusted keys.

     Keys loaded from hardware during kernel boot or compiled into the kernel
     during build are marked as being trusted automatically.  New keys can be
     loaded at runtime with add_key().  They are checked against the system
     keyring contents and if their signatures can be validated with keys that
     are already marked trusted, then they are marked trusted also and can
     thus be added into the master keyring.

     Patches from Mimi Zohar make this usable with the IMA keyrings also.

   (3) Remove the date checks on the key used to validate a module signature.

        X.509: Remove certificate date checks

     It's not reasonable to reject a signature just because the key that it was
     generated with is no longer valid datewise - especially if the kernel
     hasn't yet managed to set the system clock when the first module is
     loaded - so just remove those checks.

   (4) Make it simpler to deal with additional X.509 being loaded into the kernel.

        KEYS: Load *.x509 files into kernel keyring
        KEYS: Have make canonicalise the paths of the X.509 certs better to deduplicate

     The builder of the kernel now just places files with the extension ".x509"
     into the kernel source or build trees and they're concatenated by the
     kernel build and stuffed into the appropriate section.

   (5) Add support for userspace kerberos to use keyrings.

        KEYS: Add per-user_namespace registers for persistent per-UID kerberos caches
        KEYS: Implement a big key type that can save to tmpfs

     Fedora went to, by default, storing kerberos tickets and tokens in tmpfs.
     We looked at storing it in keyrings instead as that confers certain
     advantages such as tickets being automatically deleted after a certain
     amount of time and the ability for the kernel to get at these tokens more
     easily.

     To make this work, two things were needed:

     (a) A way for the tickets to persist beyond the lifetime of all a user's
         sessions so that cron-driven processes can still use them.

         The problem is that a user's session keyrings are deleted when the
         session that spawned them logs out and the user's user keyring is
         deleted when the UID is deleted (typically when the last log out
         happens), so neither of these places is suitable.

         I've added a system keyring into which a 'persistent' keyring is
         created for each UID on request.  Each time a user requests their
         persistent keyring, the expiry time on it is set anew.  If the user
         doesn't ask for it for, say, three days, the keyring is automatically
         expired and garbage collected using the existing gc.  All the kerberos
         tokens it held are then also gc'd.

     (b) A key type that can hold really big tickets (up to 1MB in size).

         The problem is that Active Directory can return huge tickets with lots
         of auxiliary data attached.  We don't, however, want to eat up huge
         tracts of unswappable kernel space for this, so if the ticket is
         greater than a certain size, we create a swappable shmem file and dump
         the contents in there and just live with the fact we then have an
         inode and a dentry overhead.  If the ticket is smaller than that, we
         slap it in a kmalloc()'d buffer"

* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (121 commits)
  KEYS: Fix keyring content gc scanner
  KEYS: Fix error handling in big_key instantiation
  KEYS: Fix UID check in keyctl_get_persistent()
  KEYS: The RSA public key algorithm needs to select MPILIB
  ima: define '_ima' as a builtin 'trusted' keyring
  ima: extend the measurement list to include the file signature
  kernel/system_certificate.S: use real contents instead of macro GLOBAL()
  KEYS: fix error return code in big_key_instantiate()
  KEYS: Fix keyring quota misaccounting on key replacement and unlink
  KEYS: Fix a race between negating a key and reading the error set
  KEYS: Make BIG_KEYS boolean
  apparmor: remove the "task" arg from may_change_ptraced_domain()
  apparmor: remove parent task info from audit logging
  apparmor: remove tsk field from the apparmor_audit_struct
  apparmor: fix capability to not use the current task, during reporting
  Smack: Ptrace access check mode
  ima: provide hash algo info in the xattr
  ima: enable support for larger default filedata hash algorithms
  ima: define kernel parameter 'ima_template=' to change configured default
  ima: add Kconfig default measurement list template
  ...

1 files changed, 202 insertions, 251 deletions

diff --git a/security/selinux/xfrm.c b/security/selinux/xfrm.c
index d03081886214..a91d205ec0c6 100644
--- a/security/selinux/xfrm.c
+++ b/security/selinux/xfrm.c
@@ -56,7 +56,7 @@
 atomic_t selinux_xfrm_refcount = ATOMIC_INIT(0);
 
 /*
- * Returns true if an LSM/SELinux context
+ * Returns true if the context is an LSM/SELinux context.
  */
 static inline int selinux_authorizable_ctx(struct xfrm_sec_ctx *ctx)
 {
@@ -66,7 +66,7 @@ static inline int selinux_authorizable_ctx(struct xfrm_sec_ctx *ctx)
 }
 
 /*
- * Returns true if the xfrm contains a security blob for SELinux
+ * Returns true if the xfrm contains a security blob for SELinux.
  */
 static inline int selinux_authorizable_xfrm(struct xfrm_state *x)
 {
@@ -74,48 +74,111 @@ static inline int selinux_authorizable_xfrm(struct xfrm_state *x)
 }
 
 /*
- * LSM hook implementation that authorizes that a flow can use
- * a xfrm policy rule.
+ * Allocates a xfrm_sec_state and populates it using the supplied security
+ * xfrm_user_sec_ctx context.
  */
-int selinux_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid, u8 dir)
+static int selinux_xfrm_alloc_user(struct xfrm_sec_ctx **ctxp,
+				   struct xfrm_user_sec_ctx *uctx)
 {
 	int rc;
-	u32 sel_sid;
+	const struct task_security_struct *tsec = current_security();
+	struct xfrm_sec_ctx *ctx = NULL;
+	u32 str_len;
 
-	/* Context sid is either set to label or ANY_ASSOC */
-	if (ctx) {
-		if (!selinux_authorizable_ctx(ctx))
-			return -EINVAL;
-
-		sel_sid = ctx->ctx_sid;
-	} else
-		/*
-		 * All flows should be treated as polmatch'ing an
-		 * otherwise applicable "non-labeled" policy. This
-		 * would prevent inadvertent "leaks".
-		 */
-		return 0;
+	if (ctxp == NULL || uctx == NULL ||
+	    uctx->ctx_doi != XFRM_SC_DOI_LSM ||
+	    uctx->ctx_alg != XFRM_SC_ALG_SELINUX)
+		return -EINVAL;
 
-	rc = avc_has_perm(fl_secid, sel_sid, SECCLASS_ASSOCIATION,
-			  ASSOCIATION__POLMATCH,
-			  NULL);
+	str_len = uctx->ctx_len;
+	if (str_len >= PAGE_SIZE)
+		return -ENOMEM;
 
-	if (rc == -EACCES)
-		return -ESRCH;
+	ctx = kmalloc(sizeof(*ctx) + str_len + 1, GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
 
+	ctx->ctx_doi = XFRM_SC_DOI_LSM;
+	ctx->ctx_alg = XFRM_SC_ALG_SELINUX;
+	ctx->ctx_len = str_len;
+	memcpy(ctx->ctx_str, &uctx[1], str_len);
+	ctx->ctx_str[str_len] = '\0';
+	rc = security_context_to_sid(ctx->ctx_str, str_len, &ctx->ctx_sid);
+	if (rc)
+		goto err;
+
+	rc = avc_has_perm(tsec->sid, ctx->ctx_sid,
+			  SECCLASS_ASSOCIATION, ASSOCIATION__SETCONTEXT, NULL);
+	if (rc)
+		goto err;
+
+	*ctxp = ctx;
+	atomic_inc(&selinux_xfrm_refcount);
+	return 0;
+
+err:
+	kfree(ctx);
 	return rc;
 }
 
 /*
+ * Free the xfrm_sec_ctx structure.
+ */
+static void selinux_xfrm_free(struct xfrm_sec_ctx *ctx)
+{
+	if (!ctx)
+		return;
+
+	atomic_dec(&selinux_xfrm_refcount);
+	kfree(ctx);
+}
+
+/*
+ * Authorize the deletion of a labeled SA or policy rule.
+ */
+static int selinux_xfrm_delete(struct xfrm_sec_ctx *ctx)
+{
+	const struct task_security_struct *tsec = current_security();
+
+	if (!ctx)
+		return 0;
+
+	return avc_has_perm(tsec->sid, ctx->ctx_sid,
+			    SECCLASS_ASSOCIATION, ASSOCIATION__SETCONTEXT,
+			    NULL);
+}
+
+/*
+ * LSM hook implementation that authorizes that a flow can use a xfrm policy
+ * rule.
+ */
+int selinux_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid, u8 dir)
+{
+	int rc;
+
+	/* All flows should be treated as polmatch'ing an otherwise applicable
+	 * "non-labeled" policy. This would prevent inadvertent "leaks". */
+	if (!ctx)
+		return 0;
+
+	/* Context sid is either set to label or ANY_ASSOC */
+	if (!selinux_authorizable_ctx(ctx))
+		return -EINVAL;
+
+	rc = avc_has_perm(fl_secid, ctx->ctx_sid,
+			  SECCLASS_ASSOCIATION, ASSOCIATION__POLMATCH, NULL);
+	return (rc == -EACCES ? -ESRCH : rc);
+}
+
+/*
  * LSM hook implementation that authorizes that a state matches
  * the given policy, flow combo.
  */
-
-int selinux_xfrm_state_pol_flow_match(struct xfrm_state *x, struct xfrm_policy *xp,
-			const struct flowi *fl)
+int selinux_xfrm_state_pol_flow_match(struct xfrm_state *x,
+				      struct xfrm_policy *xp,
+				      const struct flowi *fl)
 {
 	u32 state_sid;
-	int rc;
 
 	if (!xp->security)
 		if (x->security)
@@ -138,187 +201,80 @@ int selinux_xfrm_state_pol_flow_match(struct xfrm_state *x, struct xfrm_policy *
 	if (fl->flowi_secid != state_sid)
 		return 0;
 
-	rc = avc_has_perm(fl->flowi_secid, state_sid, SECCLASS_ASSOCIATION,
-			  ASSOCIATION__SENDTO,
-			  NULL)? 0:1;
-
-	/*
-	 * We don't need a separate SA Vs. policy polmatch check
-	 * since the SA is now of the same label as the flow and
-	 * a flow Vs. policy polmatch check had already happened
-	 * in selinux_xfrm_policy_lookup() above.
-	 */
-
-	return rc;
+	/* We don't need a separate SA Vs. policy polmatch check since the SA
+	 * is now of the same label as the flow and a flow Vs. policy polmatch
+	 * check had already happened in selinux_xfrm_policy_lookup() above. */
+	return (avc_has_perm(fl->flowi_secid, state_sid,
+			    SECCLASS_ASSOCIATION, ASSOCIATION__SENDTO,
+			    NULL) ? 0 : 1);
 }
 
 /*
  * LSM hook implementation that checks and/or returns the xfrm sid for the
  * incoming packet.
  */
-
 int selinux_xfrm_decode_session(struct sk_buff *skb, u32 *sid, int ckall)
 {
+	u32 sid_session = SECSID_NULL;
 	struct sec_path *sp;
 
-	*sid = SECSID_NULL;
-
 	if (skb == NULL)
-		return 0;
+		goto out;
 
 	sp = skb->sp;
 	if (sp) {
-		int i, sid_set = 0;
+		int i;
 
-		for (i = sp->len-1; i >= 0; i--) {
+		for (i = sp->len - 1; i >= 0; i--) {
 			struct xfrm_state *x = sp->xvec[i];
 			if (selinux_authorizable_xfrm(x)) {
 				struct xfrm_sec_ctx *ctx = x->security;
 
-				if (!sid_set) {
-					*sid = ctx->ctx_sid;
-					sid_set = 1;
-
+				if (sid_session == SECSID_NULL) {
+					sid_session = ctx->ctx_sid;
 					if (!ckall)
-						break;
-				} else if (*sid != ctx->ctx_sid)
+						goto out;
+				} else if (sid_session != ctx->ctx_sid) {
+					*sid = SECSID_NULL;
 					return -EINVAL;
+				}
 			}
 		}
 	}
 
-	return 0;
-}
-
-/*
- * Security blob allocation for xfrm_policy and xfrm_state
- * CTX does not have a meaningful value on input
- */
-static int selinux_xfrm_sec_ctx_alloc(struct xfrm_sec_ctx **ctxp,
-	struct xfrm_user_sec_ctx *uctx, u32 sid)
-{
-	int rc = 0;
-	const struct task_security_struct *tsec = current_security();
-	struct xfrm_sec_ctx *ctx = NULL;
-	char *ctx_str = NULL;
-	u32 str_len;
-
-	BUG_ON(uctx && sid);
-
-	if (!uctx)
-		goto not_from_user;
-
-	if (uctx->ctx_alg != XFRM_SC_ALG_SELINUX)
-		return -EINVAL;
-
-	str_len = uctx->ctx_len;
-	if (str_len >= PAGE_SIZE)
-		return -ENOMEM;
-
-	*ctxp = ctx = kmalloc(sizeof(*ctx) +
-			      str_len + 1,
-			      GFP_KERNEL);
-
-	if (!ctx)
-		return -ENOMEM;
-
-	ctx->ctx_doi = uctx->ctx_doi;
-	ctx->ctx_len = str_len;
-	ctx->ctx_alg = uctx->ctx_alg;
-
-	memcpy(ctx->ctx_str,
-	       uctx+1,
-	       str_len);
-	ctx->ctx_str[str_len] = 0;
-	rc = security_context_to_sid(ctx->ctx_str,
-				     str_len,
-				     &ctx->ctx_sid);
-
-	if (rc)
-		goto out;
-
-	/*
-	 * Does the subject have permission to set security context?
-	 */
-	rc = avc_has_perm(tsec->sid, ctx->ctx_sid,
-			  SECCLASS_ASSOCIATION,
-			  ASSOCIATION__SETCONTEXT, NULL);
-	if (rc)
-		goto out;
-
-	return rc;
-
-not_from_user:
-	rc = security_sid_to_context(sid, &ctx_str, &str_len);
-	if (rc)
-		goto out;
-
-	*ctxp = ctx = kmalloc(sizeof(*ctx) +
-			      str_len,
-			      GFP_ATOMIC);
-
-	if (!ctx) {
-		rc = -ENOMEM;
-		goto out;
-	}
-
-	ctx->ctx_doi = XFRM_SC_DOI_LSM;
-	ctx->ctx_alg = XFRM_SC_ALG_SELINUX;
-	ctx->ctx_sid = sid;
-	ctx->ctx_len = str_len;
-	memcpy(ctx->ctx_str,
-	       ctx_str,
-	       str_len);
-
-	goto out2;
-
 out:
-	*ctxp = NULL;
-	kfree(ctx);
-out2:
-	kfree(ctx_str);
-	return rc;
+	*sid = sid_session;
+	return 0;
 }
 
 /*
- * LSM hook implementation that allocs and transfers uctx spec to
- * xfrm_policy.
+ * LSM hook implementation that allocs and transfers uctx spec to xfrm_policy.
  */
 int selinux_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp,
 			      struct xfrm_user_sec_ctx *uctx)
 {
-	int err;
-
-	BUG_ON(!uctx);
-
-	err = selinux_xfrm_sec_ctx_alloc(ctxp, uctx, 0);
-	if (err == 0)
-		atomic_inc(&selinux_xfrm_refcount);
-
-	return err;
+	return selinux_xfrm_alloc_user(ctxp, uctx);
 }
 
-
 /*
- * LSM hook implementation that copies security data structure from old to
- * new for policy cloning.
+ * LSM hook implementation that copies security data structure from old to new
+ * for policy cloning.
  */
 int selinux_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx,
 			      struct xfrm_sec_ctx **new_ctxp)
 {
 	struct xfrm_sec_ctx *new_ctx;
 
-	if (old_ctx) {
-		new_ctx = kmalloc(sizeof(*old_ctx) + old_ctx->ctx_len,
-				  GFP_ATOMIC);
-		if (!new_ctx)
-			return -ENOMEM;
+	if (!old_ctx)
+		return 0;
+
+	new_ctx = kmemdup(old_ctx, sizeof(*old_ctx) + old_ctx->ctx_len,
+			  GFP_ATOMIC);
+	if (!new_ctx)
+		return -ENOMEM;
+	atomic_inc(&selinux_xfrm_refcount);
+	*new_ctxp = new_ctx;
 
-		memcpy(new_ctx, old_ctx, sizeof(*new_ctx));
-		memcpy(new_ctx->ctx_str, old_ctx->ctx_str, new_ctx->ctx_len);
-		atomic_inc(&selinux_xfrm_refcount);
-		*new_ctxp = new_ctx;
-	}
 	return 0;
 }
 
@@ -327,8 +283,7 @@ int selinux_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx,
  */
 void selinux_xfrm_policy_free(struct xfrm_sec_ctx *ctx)
 {
-	atomic_dec(&selinux_xfrm_refcount);
-	kfree(ctx);
+	selinux_xfrm_free(ctx);
 }
 
 /*
@@ -336,31 +291,55 @@ void selinux_xfrm_policy_free(struct xfrm_sec_ctx *ctx)
  */
 int selinux_xfrm_policy_delete(struct xfrm_sec_ctx *ctx)
 {
-	const struct task_security_struct *tsec = current_security();
-
-	if (!ctx)
-		return 0;
+	return selinux_xfrm_delete(ctx);
+}
 
-	return avc_has_perm(tsec->sid, ctx->ctx_sid,
-			    SECCLASS_ASSOCIATION, ASSOCIATION__SETCONTEXT,
-			    NULL);
+/*
+ * LSM hook implementation that allocates a xfrm_sec_state, populates it using
+ * the supplied security context, and assigns it to the xfrm_state.
+ */
+int selinux_xfrm_state_alloc(struct xfrm_state *x,
+			     struct xfrm_user_sec_ctx *uctx)
+{
+	return selinux_xfrm_alloc_user(&x->security, uctx);
 }
 
 /*
- * LSM hook implementation that allocs and transfers sec_ctx spec to
- * xfrm_state.
+ * LSM hook implementation that allocates a xfrm_sec_state and populates based
+ * on a secid.
  */
-int selinux_xfrm_state_alloc(struct xfrm_state *x, struct xfrm_user_sec_ctx *uctx,
-		u32 secid)
+int selinux_xfrm_state_alloc_acquire(struct xfrm_state *x,
+				     struct xfrm_sec_ctx *polsec, u32 secid)
 {
-	int err;
+	int rc;
+	struct xfrm_sec_ctx *ctx;
+	char *ctx_str = NULL;
+	int str_len;
+
+	if (!polsec)
+		return 0;
 
-	BUG_ON(!x);
+	if (secid == 0)
+		return -EINVAL;
 
-	err = selinux_xfrm_sec_ctx_alloc(&x->security, uctx, secid);
-	if (err == 0)
-		atomic_inc(&selinux_xfrm_refcount);
-	return err;
+	rc = security_sid_to_context(secid, &ctx_str, &str_len);
+	if (rc)
+		return rc;
+
+	ctx = kmalloc(sizeof(*ctx) + str_len, GFP_ATOMIC);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->ctx_doi = XFRM_SC_DOI_LSM;
+	ctx->ctx_alg = XFRM_SC_ALG_SELINUX;
+	ctx->ctx_sid = secid;
+	ctx->ctx_len = str_len;
+	memcpy(ctx->ctx_str, ctx_str, str_len);
+	kfree(ctx_str);
+
+	x->security = ctx;
+	atomic_inc(&selinux_xfrm_refcount);
+	return 0;
 }
 
 /*
@@ -368,24 +347,15 @@ int selinux_xfrm_state_alloc(struct xfrm_state *x, struct xfrm_user_sec_ctx *uct
  */
 void selinux_xfrm_state_free(struct xfrm_state *x)
 {
-	atomic_dec(&selinux_xfrm_refcount);
-	kfree(x->security);
+	selinux_xfrm_free(x->security);
 }
 
- /*
-  * LSM hook implementation that authorizes deletion of labeled SAs.
-  */
+/*
+ * LSM hook implementation that authorizes deletion of labeled SAs.
+ */
 int selinux_xfrm_state_delete(struct xfrm_state *x)
 {
-	const struct task_security_struct *tsec = current_security();
-	struct xfrm_sec_ctx *ctx = x->security;
-
-	if (!ctx)
-		return 0;
-
-	return avc_has_perm(tsec->sid, ctx->ctx_sid,
-			    SECCLASS_ASSOCIATION, ASSOCIATION__SETCONTEXT,
-			    NULL);
+	return selinux_xfrm_delete(x->security);
 }
 
 /*
@@ -395,14 +365,12 @@ int selinux_xfrm_state_delete(struct xfrm_state *x)
  * we need to check for unlabelled access since this may not have
  * gone thru the IPSec process.
  */
-int selinux_xfrm_sock_rcv_skb(u32 isec_sid, struct sk_buff *skb,
-				struct common_audit_data *ad)
+int selinux_xfrm_sock_rcv_skb(u32 sk_sid, struct sk_buff *skb,
+			      struct common_audit_data *ad)
 {
-	int i, rc = 0;
-	struct sec_path *sp;
-	u32 sel_sid = SECINITSID_UNLABELED;
-
-	sp = skb->sp;
+	int i;
+	struct sec_path *sp = skb->sp;
+	u32 peer_sid = SECINITSID_UNLABELED;
 
 	if (sp) {
 		for (i = 0; i < sp->len; i++) {
@@ -410,23 +378,17 @@ int selinux_xfrm_sock_rcv_skb(u32 isec_sid, struct sk_buff *skb,
 
 			if (x && selinux_authorizable_xfrm(x)) {
 				struct xfrm_sec_ctx *ctx = x->security;
-				sel_sid = ctx->ctx_sid;
+				peer_sid = ctx->ctx_sid;
 				break;
 			}
 		}
 	}
 
-	/*
-	 * This check even when there's no association involved is
-	 * intended, according to Trent Jaeger, to make sure a
-	 * process can't engage in non-ipsec communication unless
-	 * explicitly allowed by policy.
-	 */
-
-	rc = avc_has_perm(isec_sid, sel_sid, SECCLASS_ASSOCIATION,
-			  ASSOCIATION__RECVFROM, ad);
-
-	return rc;
+	/* This check even when there's no association involved is intended,
+	 * according to Trent Jaeger, to make sure a process can't engage in
+	 * non-IPsec communication unless explicitly allowed by policy. */
+	return avc_has_perm(sk_sid, peer_sid,
+			    SECCLASS_ASSOCIATION, ASSOCIATION__RECVFROM, ad);
 }
 
 /*
@@ -436,49 +398,38 @@ int selinux_xfrm_sock_rcv_skb(u32 isec_sid, struct sk_buff *skb,
  * If we do have a authorizable security association, then it has already been
  * checked in the selinux_xfrm_state_pol_flow_match hook above.
  */
-int selinux_xfrm_postroute_last(u32 isec_sid, struct sk_buff *skb,
-					struct common_audit_data *ad, u8 proto)
+int selinux_xfrm_postroute_last(u32 sk_sid, struct sk_buff *skb,
+				struct common_audit_data *ad, u8 proto)
 {
 	struct dst_entry *dst;
-	int rc = 0;
-
-	dst = skb_dst(skb);
-
-	if (dst) {
-		struct dst_entry *dst_test;
-
-		for (dst_test = dst; dst_test != NULL;
-		     dst_test = dst_test->child) {
-			struct xfrm_state *x = dst_test->xfrm;
-
-			if (x && selinux_authorizable_xfrm(x))
-				goto out;
-		}
-	}
 
 	switch (proto) {
 	case IPPROTO_AH:
 	case IPPROTO_ESP:
 	case IPPROTO_COMP:
-		/*
-		 * We should have already seen this packet once before
-		 * it underwent xfrm(s). No need to subject it to the
-		 * unlabeled check.
-		 */
-		goto out;
+		/* We should have already seen this packet once before it
+		 * underwent xfrm(s). No need to subject it to the unlabeled
+		 * check. */
+		return 0;
 	default:
 		break;
 	}
 
-	/*
-	 * This check even when there's no association involved is
-	 * intended, according to Trent Jaeger, to make sure a
-	 * process can't engage in non-ipsec communication unless
-	 * explicitly allowed by policy.
-	 */
+	dst = skb_dst(skb);
+	if (dst) {
+		struct dst_entry *iter;
 
-	rc = avc_has_perm(isec_sid, SECINITSID_UNLABELED, SECCLASS_ASSOCIATION,
-			  ASSOCIATION__SENDTO, ad);
-out:
-	return rc;
+		for (iter = dst; iter != NULL; iter = iter->child) {
+			struct xfrm_state *x = iter->xfrm;
+
+			if (x && selinux_authorizable_xfrm(x))
+				return 0;
+		}
+	}
+
+	/* This check even when there's no association involved is intended,
+	 * according to Trent Jaeger, to make sure a process can't engage in
+	 * non-IPsec communication unless explicitly allowed by policy. */
+	return avc_has_perm(sk_sid, SECINITSID_UNLABELED,
+			    SECCLASS_ASSOCIATION, ASSOCIATION__SENDTO, ad);
 }