Inter-revision diff: patch 16

Comparing v20 (message) to v8 (message)

--- v20
+++ v8
@@ -1,142 +1,628 @@
-Change the security_inode_getsecctx() interface to fill
-a lsmcontext structure instead of data and length pointers.
-This provides the information about which LSM created the
-context so that security_release_secctx() can use the
-correct hook.
+Add a new lsmcontext data structure to hold all the information
+about a "security context", including the string, its size and
+which LSM allocated the string. The allocation information is
+necessary because LSMs have different policies regarding the
+lifecycle of these strings. SELinux allocates and destroys
+them on each use, whereas Smack provides a pointer to an entry
+in a list that never goes away.
 
-Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
+Reviewed-by: Kees Cook <keescook@chromium.org>
+Reviewed-by: John Johansen <john.johansen@canonical.com>
 Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
 ---
- fs/nfsd/nfs4xdr.c        | 23 +++++++++--------------
- include/linux/security.h |  5 +++--
- security/security.c      | 13 +++++++++++--
- 3 files changed, 23 insertions(+), 18 deletions(-)
+ drivers/android/binder.c                | 10 +++++--
+ fs/kernfs/dir.c                         | 10 +++++--
+ fs/kernfs/inode.c                       |  7 +++--
+ fs/nfs/nfs4proc.c                       |  8 +++--
+ fs/nfsd/nfs4xdr.c                       |  7 +++--
+ include/linux/security.h                | 39 +++++++++++++++++++++++--
+ include/net/scm.h                       |  5 +++-
+ kernel/audit.c                          | 14 ++++++---
+ kernel/auditsc.c                        | 12 ++++++--
+ net/ipv4/ip_sockglue.c                  |  4 ++-
+ net/netfilter/nf_conntrack_netlink.c    |  4 ++-
+ net/netfilter/nf_conntrack_standalone.c |  4 ++-
+ net/netfilter/nfnetlink_queue.c         | 13 ++++++---
+ net/netlabel/netlabel_unlabeled.c       | 19 +++++++++---
+ net/netlabel/netlabel_user.c            |  4 ++-
+ security/security.c                     | 18 ++++++++----
+ security/smack/smack_lsm.c              | 14 ++++++---
+ 17 files changed, 148 insertions(+), 44 deletions(-)
 
+diff --git a/drivers/android/binder.c b/drivers/android/binder.c
+index 144ac4f1c24f..89e574be34cc 100644
+--- a/drivers/android/binder.c
++++ b/drivers/android/binder.c
+@@ -2876,6 +2876,7 @@ static void binder_transaction(struct binder_proc *proc,
+ 	int t_debug_id = atomic_inc_return(&binder_last_id);
+ 	char *secctx = NULL;
+ 	u32 secctx_sz = 0;
++	struct lsmcontext scaff; /* scaffolding */
+ 
+ 	e = binder_transaction_log_add(&binder_transaction_log);
+ 	e->debug_id = t_debug_id;
+@@ -3158,7 +3159,8 @@ static void binder_transaction(struct binder_proc *proc,
+ 		binder_alloc_copy_to_buffer(&target_proc->alloc,
+ 					    t->buffer, buf_offset,
+ 					    secctx, secctx_sz);
+-		security_release_secctx(secctx, secctx_sz);
++		lsmcontext_init(&scaff, secctx, secctx_sz, 0);
++		security_release_secctx(&scaff);
+ 		secctx = NULL;
+ 	}
+ 	t->buffer->debug_id = t->debug_id;
+@@ -3479,8 +3481,10 @@ static void binder_transaction(struct binder_proc *proc,
+ 	t->buffer->transaction = NULL;
+ 	binder_alloc_free_buf(&target_proc->alloc, t->buffer);
+ err_binder_alloc_buf_failed:
+-	if (secctx)
+-		security_release_secctx(secctx, secctx_sz);
++	if (secctx) {
++		lsmcontext_init(&scaff, secctx, secctx_sz, 0);
++		security_release_secctx(&scaff);
++	}
+ err_get_secctx_failed:
+ 	kfree(tcomplete);
+ 	binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
+diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
+index b84d635567d3..c8362b6d556e 100644
+--- a/fs/kernfs/dir.c
++++ b/fs/kernfs/dir.c
+@@ -532,9 +532,13 @@ void kernfs_put(struct kernfs_node *kn)
+ 	kfree_const(kn->name);
+ 
+ 	if (kn->iattr) {
+-		if (kn->iattr->ia_secdata)
+-			security_release_secctx(kn->iattr->ia_secdata,
+-						kn->iattr->ia_secdata_len);
++		struct lsmcontext scaff; /* scaffolding */
++
++		if (kn->iattr->ia_secdata) {
++			lsmcontext_init(&scaff, kn->iattr->ia_secdata,
++					kn->iattr->ia_secdata_len, 0);
++			security_release_secctx(&scaff);
++		}
+ 		simple_xattrs_free(&kn->iattr->xattrs);
+ 		kmem_cache_free(kernfs_iattrs_cache, kn->iattr);
+ 	}
+diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
+index 0c1fd945ce42..02cde9dac5ee 100644
+--- a/fs/kernfs/inode.c
++++ b/fs/kernfs/inode.c
+@@ -349,6 +349,7 @@ static int kernfs_security_xattr_set(const struct xattr_handler *handler,
+ {
+ 	struct kernfs_node *kn = inode->i_private;
+ 	struct kernfs_iattrs *attrs;
++	struct lsmcontext context;
+ 	void *secdata;
+ 	u32 secdata_len = 0;
+ 	int error;
+@@ -368,8 +369,10 @@ static int kernfs_security_xattr_set(const struct xattr_handler *handler,
+ 	error = kernfs_node_setsecdata(attrs, &secdata, &secdata_len);
+ 	mutex_unlock(&kernfs_mutex);
+ 
+-	if (secdata)
+-		security_release_secctx(secdata, secdata_len);
++	if (secdata) {
++		lsmcontext_init(&context, secdata, secdata_len, 0);
++		security_release_secctx(&context);
++	}
+ 	return error;
+ }
+ 
+diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
+index 4dbb0ee23432..af1c0db29c39 100644
+--- a/fs/nfs/nfs4proc.c
++++ b/fs/nfs/nfs4proc.c
+@@ -131,8 +131,12 @@ nfs4_label_init_security(struct inode *dir, struct dentry *dentry,
+ static inline void
+ nfs4_label_release_security(struct nfs4_label *label)
+ {
+-	if (label)
+-		security_release_secctx(label->label, label->len);
++	struct lsmcontext scaff; /* scaffolding */
++
++	if (label) {
++		lsmcontext_init(&scaff, label->label, label->len, 0);
++		security_release_secctx(&scaff);
++	}
+ }
+ static inline u32 *nfs4_bitmask(struct nfs_server *server, struct nfs4_label *label)
+ {
 diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
-index 0fc505392728..9352c05f3086 100644
+index 3de42a729093..bb3db033e144 100644
 --- a/fs/nfsd/nfs4xdr.c
 +++ b/fs/nfsd/nfs4xdr.c
-@@ -2600,11 +2600,11 @@ nfsd4_encode_layout_types(struct xdr_stream *xdr, u32 layout_types)
- #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
- static inline __be32
- nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
--			    void *context, int len)
-+			    struct lsmcontext *context)
- {
- 	__be32 *p;
- 
--	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
-+	p = xdr_reserve_space(xdr, context->len + 4 + 4 + 4);
- 	if (!p)
- 		return nfserr_resource;
- 
-@@ -2614,13 +2614,13 @@ nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
- 	 */
- 	*p++ = cpu_to_be32(0); /* lfs */
- 	*p++ = cpu_to_be32(0); /* pi */
--	p = xdr_encode_opaque(p, context, len);
-+	p = xdr_encode_opaque(p, context->context, context->len);
- 	return 0;
- }
- #else
- static inline __be32
- nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
--			    void *context, int len)
-+			    struct lsmcontext *context)
- { return 0; }
- #endif
- 
-@@ -2717,9 +2717,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
+@@ -2420,6 +2420,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
+ 	__be32 status;
  	int err;
  	struct nfs4_acl *acl = NULL;
- #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
--	struct lsmcontext scaff; /* scaffolding */
--	void *context = NULL;
--	int contextlen;
-+	struct lsmcontext context = { };
- #endif
++	struct lsmcontext scaff; /* scaffolding */
+ 	void *context = NULL;
+ 	int contextlen;
  	bool contextsupport = false;
- 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
-@@ -2777,7 +2775,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
- 	     bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
- 		if (exp->ex_flags & NFSEXP_SECURITY_LABEL)
- 			err = security_inode_getsecctx(d_inode(dentry),
--						&context, &contextlen);
-+						       &context);
- 		else
- 			err = -EOPNOTSUPP;
- 		contextsupport = (err == 0);
-@@ -3207,8 +3205,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
- 
- #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
- 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
--		status = nfsd4_encode_security_label(xdr, rqstp, context,
--								contextlen);
-+		status = nfsd4_encode_security_label(xdr, rqstp, &context);
- 		if (status)
- 			goto out;
- 	}
-@@ -3229,10 +3226,8 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
+@@ -2919,8 +2920,10 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
  
  out:
  #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
--	if (context) {
--		lsmcontext_init(&scaff, context, contextlen, 0); /*scaffolding*/
--		security_release_secctx(&scaff);
--	}
-+	if (context.context)
-+		security_release_secctx(&context);
+-	if (context)
+-		security_release_secctx(context, contextlen);
++	if (context) {
++		lsmcontext_init(&scaff, context, contextlen, 0); /*scaffolding*/
++		security_release_secctx(&scaff);
++	}
  #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
  	kfree(acl);
  	if (tempfh) {
 diff --git a/include/linux/security.h b/include/linux/security.h
-index de6b44751dee..40260bfc3a0d 100644
+index d310fa3942ce..046012a7255f 100644
 --- a/include/linux/security.h
 +++ b/include/linux/security.h
-@@ -561,7 +561,7 @@ void security_release_secctx(struct lsmcontext *cp);
+@@ -76,6 +76,41 @@ enum lsm_event {
+ 	LSM_POLICY_CHANGE,
+ };
+ 
++/*
++ * A "security context" is the text representation of
++ * the information used by LSMs.
++ * This structure contains the string, its length, and which LSM
++ * it is useful for.
++ */
++struct lsmcontext {
++	char	*context;	/* Provided by the module */
++	u32	len;
++	int	slot;		/* Identifies the module */
++};
++
++/**
++ * lsmcontext_init - initialize an lsmcontext structure.
++ * @cp: Pointer to the context to initialize
++ * @context: Initial context, or NULL
++ * @size: Size of context, or 0
++ * @slot: Which LSM provided the context
++ *
++ * Fill in the lsmcontext from the provided information.
++ * This is a scaffolding function that will be removed when
++ * lsmcontext integration is complete.
++ */
++static inline void lsmcontext_init(struct lsmcontext *cp, char *context,
++				   u32 size, int slot)
++{
++	cp->slot = slot;
++	cp->context = context;
++
++	if (context == NULL || size == 0)
++		cp->len = 0;
++	else
++		cp->len = strlen(context);
++}
++
+ /*
+  * Data exported by the security modules
+  *
+@@ -449,7 +484,7 @@ int security_ismaclabel(const char *name);
+ int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen);
+ int security_secctx_to_secid(const char *secdata, u32 seclen,
+ 			     struct lsmblob *blob);
+-void security_release_secctx(char *secdata, u32 seclen);
++void security_release_secctx(struct lsmcontext *cp);
+ 
  void security_inode_invalidate_secctx(struct inode *inode);
  int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen);
- int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen);
--int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen);
-+int security_inode_getsecctx(struct inode *inode, struct lsmcontext *cp);
- int security_locked_down(enum lockdown_reason what);
- #else /* CONFIG_SECURITY */
- 
-@@ -1400,7 +1400,8 @@ static inline int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32
- {
+@@ -1240,7 +1275,7 @@ static inline int security_secctx_to_secid(const char *secdata,
  	return -EOPNOTSUPP;
  }
--static inline int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
-+static inline int security_inode_getsecctx(struct inode *inode,
-+					   struct lsmcontext *cp)
- {
- 	return -EOPNOTSUPP;
- }
+ 
+-static inline void security_release_secctx(char *secdata, u32 seclen)
++static inline void security_release_secctx(struct lsmcontext *cp)
+ {
+ }
+ 
+diff --git a/include/net/scm.h b/include/net/scm.h
+index 31ae605fcc0a..30ba801c91bd 100644
+--- a/include/net/scm.h
++++ b/include/net/scm.h
+@@ -92,6 +92,7 @@ static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
+ #ifdef CONFIG_SECURITY_NETWORK
+ static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
+ {
++	struct lsmcontext context;
+ 	char *secdata;
+ 	u32 seclen;
+ 	int err;
+@@ -102,7 +103,9 @@ static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct sc
+ 
+ 		if (!err) {
+ 			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
+-			security_release_secctx(secdata, seclen);
++			/*scaffolding*/
++			lsmcontext_init(&context, secdata, seclen, 0);
++			security_release_secctx(&context);
+ 		}
+ 	}
+ }
+diff --git a/kernel/audit.c b/kernel/audit.c
+index 1b51e907f131..f844a2a642e6 100644
+--- a/kernel/audit.c
++++ b/kernel/audit.c
+@@ -1193,6 +1193,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+ 	struct audit_sig_info   *sig_data;
+ 	char			*ctx = NULL;
+ 	u32			len;
++	struct lsmcontext	scaff; /* scaffolding */
+ 
+ 	err = audit_netlink_ok(skb, msg_type);
+ 	if (err)
+@@ -1437,15 +1438,18 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+ 		}
+ 		sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
+ 		if (!sig_data) {
+-			if (lsmblob_is_set(&audit_sig_lsm))
+-				security_release_secctx(ctx, len);
++			if (lsmblob_is_set(&audit_sig_lsm)) {
++				lsmcontext_init(&scaff, ctx, len, 0);
++				security_release_secctx(&scaff);
++			}
+ 			return -ENOMEM;
+ 		}
+ 		sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
+ 		sig_data->pid = audit_sig_pid;
+ 		if (lsmblob_is_set(&audit_sig_lsm)) {
+ 			memcpy(sig_data->ctx, ctx, len);
+-			security_release_secctx(ctx, len);
++			lsmcontext_init(&scaff, ctx, len, 0);
++			security_release_secctx(&scaff);
+ 		}
+ 		audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0,
+ 				 sig_data, sizeof(*sig_data) + len);
+@@ -2074,6 +2078,7 @@ int audit_log_task_context(struct audit_buffer *ab)
+ 	unsigned len;
+ 	int error;
+ 	struct lsmblob blob;
++	struct lsmcontext scaff; /* scaffolding */
+ 
+ 	security_task_getsecid(current, &blob);
+ 	if (!lsmblob_is_set(&blob))
+@@ -2087,7 +2092,8 @@ int audit_log_task_context(struct audit_buffer *ab)
+ 	}
+ 
+ 	audit_log_format(ab, " subj=%s", ctx);
+-	security_release_secctx(ctx, len);
++	lsmcontext_init(&scaff, ctx, len, 0);
++	security_release_secctx(&scaff);
+ 	return 0;
+ 
+ error_path:
+diff --git a/kernel/auditsc.c b/kernel/auditsc.c
+index c7aa39bda5cc..9fab0e7d90c3 100644
+--- a/kernel/auditsc.c
++++ b/kernel/auditsc.c
+@@ -943,6 +943,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
+ 				 struct lsmblob *blob, char *comm)
+ {
+ 	struct audit_buffer *ab;
++	struct lsmcontext lsmcxt;
+ 	char *ctx = NULL;
+ 	u32 len;
+ 	int rc = 0;
+@@ -960,7 +961,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
+ 			rc = 1;
+ 		} else {
+ 			audit_log_format(ab, " obj=%s", ctx);
+-			security_release_secctx(ctx, len);
++			lsmcontext_init(&lsmcxt, ctx, len, 0); /*scaffolding*/
++			security_release_secctx(&lsmcxt);
+ 		}
+ 	}
+ 	audit_log_format(ab, " ocomm=");
+@@ -1172,6 +1174,7 @@ static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
+ 
+ static void show_special(struct audit_context *context, int *call_panic)
+ {
++	struct lsmcontext lsmcxt;
+ 	struct audit_buffer *ab;
+ 	int i;
+ 
+@@ -1205,7 +1208,8 @@ static void show_special(struct audit_context *context, int *call_panic)
+ 				*call_panic = 1;
+ 			} else {
+ 				audit_log_format(ab, " obj=%s", ctx);
+-				security_release_secctx(ctx, len);
++				lsmcontext_init(&lsmcxt, ctx, len, 0);
++				security_release_secctx(&lsmcxt);
+ 			}
+ 		}
+ 		if (context->ipc.has_perm) {
+@@ -1352,6 +1356,7 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
+ 		char *ctx = NULL;
+ 		u32 len;
+ 		struct lsmblob blob;
++		struct lsmcontext lsmcxt;
+ 
+ 		lsmblob_init(&blob, n->osid);
+ 		if (security_secid_to_secctx(&blob, &ctx, &len)) {
+@@ -1360,7 +1365,8 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
+ 				*call_panic = 2;
+ 		} else {
+ 			audit_log_format(ab, " obj=%s", ctx);
+-			security_release_secctx(ctx, len);
++			lsmcontext_init(&lsmcxt, ctx, len, 0); /* scaffolding */
++			security_release_secctx(&lsmcxt);
+ 		}
+ 	}
+ 
+diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
+index e05f4ef68bd8..7834c357b60b 100644
+--- a/net/ipv4/ip_sockglue.c
++++ b/net/ipv4/ip_sockglue.c
+@@ -130,6 +130,7 @@ static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb,
+ 
+ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
+ {
++	struct lsmcontext context;
+ 	struct lsmblob lb;
+ 	char *secdata;
+ 	u32 seclen;
+@@ -144,7 +145,8 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
+ 		return;
+ 
+ 	put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
+-	security_release_secctx(secdata, seclen);
++	lsmcontext_init(&context, secdata, seclen, 0); /* scaffolding */
++	security_release_secctx(&context);
+ }
+ 
+ static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
+diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
+index ca0968f13240..6954e6600583 100644
+--- a/net/netfilter/nf_conntrack_netlink.c
++++ b/net/netfilter/nf_conntrack_netlink.c
+@@ -331,6 +331,7 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
+ 	int len, ret;
+ 	char *secctx;
+ 	struct lsmblob blob;
++	struct lsmcontext context;
+ 
+ 	lsmblob_init(&blob, ct->secmark);
+ 	ret = security_secid_to_secctx(&blob, &secctx, &len);
+@@ -348,7 +349,8 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
+ 
+ 	ret = 0;
+ nla_put_failure:
+-	security_release_secctx(secctx, len);
++	lsmcontext_init(&context, secctx, len, 0); /* scaffolding */
++	security_release_secctx(&context);
+ 	return ret;
+ }
+ #else
+diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
+index c793103f3cd7..79158ad0486e 100644
+--- a/net/netfilter/nf_conntrack_standalone.c
++++ b/net/netfilter/nf_conntrack_standalone.c
+@@ -176,6 +176,7 @@ static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
+ 	u32 len;
+ 	char *secctx;
+ 	struct lsmblob blob;
++	struct lsmcontext context;
+ 
+ 	lsmblob_init(&blob, ct->secmark);
+ 	ret = security_secid_to_secctx(&blob, &secctx, &len);
+@@ -184,7 +185,8 @@ static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
+ 
+ 	seq_printf(s, "secctx=%s ", secctx);
+ 
+-	security_release_secctx(secctx, len);
++	lsmcontext_init(&context, secctx, len, 0); /* scaffolding */
++	security_release_secctx(&context);
+ }
+ #else
+ static inline void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
+diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
+index 59211bff90ab..fe8403ef4e89 100644
+--- a/net/netfilter/nfnetlink_queue.c
++++ b/net/netfilter/nfnetlink_queue.c
+@@ -399,6 +399,7 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
+ 	enum ip_conntrack_info uninitialized_var(ctinfo);
+ 	struct nfnl_ct_hook *nfnl_ct;
+ 	bool csum_verify;
++	struct lsmcontext scaff; /* scaffolding */
+ 	char *secdata = NULL;
+ 	u32 seclen = 0;
+ 
+@@ -629,8 +630,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
+ 	}
+ 
+ 	nlh->nlmsg_len = skb->len;
+-	if (seclen)
+-		security_release_secctx(secdata, seclen);
++	if (seclen) {
++		lsmcontext_init(&scaff, secdata, seclen, 0);
++		security_release_secctx(&scaff);
++	}
+ 	return skb;
+ 
+ nla_put_failure:
+@@ -638,8 +641,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
+ 	kfree_skb(skb);
+ 	net_err_ratelimited("nf_queue: error creating packet message\n");
+ nlmsg_failure:
+-	if (seclen)
+-		security_release_secctx(secdata, seclen);
++	if (seclen) {
++		lsmcontext_init(&scaff, secdata, seclen, 0);
++		security_release_secctx(&scaff);
++	}
+ 	return NULL;
+ }
+ 
+diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
+index 2294aa9471e6..15b1945853be 100644
+--- a/net/netlabel/netlabel_unlabeled.c
++++ b/net/netlabel/netlabel_unlabeled.c
+@@ -387,6 +387,7 @@ int netlbl_unlhsh_add(struct net *net,
+ 	struct net_device *dev;
+ 	struct netlbl_unlhsh_iface *iface;
+ 	struct audit_buffer *audit_buf = NULL;
++	struct lsmcontext context;
+ 	char *secctx = NULL;
+ 	u32 secctx_len;
+ 	struct lsmblob blob;
+@@ -457,7 +458,9 @@ int netlbl_unlhsh_add(struct net *net,
+ 					     &secctx,
+ 					     &secctx_len) == 0) {
+ 			audit_log_format(audit_buf, " sec_obj=%s", secctx);
+-			security_release_secctx(secctx, secctx_len);
++			/* scaffolding */
++			lsmcontext_init(&context, secctx, secctx_len, 0);
++			security_release_secctx(&context);
+ 		}
+ 		audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
+ 		audit_log_end(audit_buf);
+@@ -488,6 +491,7 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
+ 	struct netlbl_unlhsh_addr4 *entry;
+ 	struct audit_buffer *audit_buf;
+ 	struct net_device *dev;
++	struct lsmcontext context;
+ 	char *secctx;
+ 	u32 secctx_len;
+ 	struct lsmblob blob;
+@@ -516,7 +520,9 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
+ 		    security_secid_to_secctx(&blob,
+ 					     &secctx, &secctx_len) == 0) {
+ 			audit_log_format(audit_buf, " sec_obj=%s", secctx);
+-			security_release_secctx(secctx, secctx_len);
++			/* scaffolding */
++			lsmcontext_init(&context, secctx, secctx_len, 0);
++			security_release_secctx(&context);
+ 		}
+ 		audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
+ 		audit_log_end(audit_buf);
+@@ -553,6 +559,7 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
+ 	struct netlbl_unlhsh_addr6 *entry;
+ 	struct audit_buffer *audit_buf;
+ 	struct net_device *dev;
++	struct lsmcontext context;
+ 	char *secctx;
+ 	u32 secctx_len;
+ 	struct lsmblob blob;
+@@ -580,7 +587,8 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
+ 		    security_secid_to_secctx(&blob,
+ 					     &secctx, &secctx_len) == 0) {
+ 			audit_log_format(audit_buf, " sec_obj=%s", secctx);
+-			security_release_secctx(secctx, secctx_len);
++			lsmcontext_init(&context, secctx, secctx_len, 0);
++			security_release_secctx(&context);
+ 		}
+ 		audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
+ 		audit_log_end(audit_buf);
+@@ -1094,6 +1102,7 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
+ 	int ret_val = -ENOMEM;
+ 	struct netlbl_unlhsh_walk_arg *cb_arg = arg;
+ 	struct net_device *dev;
++	struct lsmcontext context;
+ 	void *data;
+ 	u32 secid;
+ 	char *secctx;
+@@ -1161,7 +1170,9 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
+ 			  NLBL_UNLABEL_A_SECCTX,
+ 			  secctx_len,
+ 			  secctx);
+-	security_release_secctx(secctx, secctx_len);
++	/* scaffolding */
++	lsmcontext_init(&context, secctx, secctx_len, 0);
++	security_release_secctx(&context);
+ 	if (ret_val != 0)
+ 		goto list_cb_failure;
+ 
+diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c
+index 2ccc6567e2a2..94aea4985b74 100644
+--- a/net/netlabel/netlabel_user.c
++++ b/net/netlabel/netlabel_user.c
+@@ -98,6 +98,7 @@ struct audit_buffer *netlbl_audit_start_common(int type,
+ 					       struct netlbl_audit *audit_info)
+ {
+ 	struct audit_buffer *audit_buf;
++	struct lsmcontext context;
+ 	char *secctx;
+ 	u32 secctx_len;
+ 	struct lsmblob blob;
+@@ -117,7 +118,8 @@ struct audit_buffer *netlbl_audit_start_common(int type,
+ 	if (audit_info->secid != 0 &&
+ 	    security_secid_to_secctx(&blob, &secctx, &secctx_len) == 0) {
+ 		audit_log_format(audit_buf, " subj=%s", secctx);
+-		security_release_secctx(secctx, secctx_len);
++		lsmcontext_init(&context, secctx, secctx_len, 0);/*scaffolding*/
++		security_release_secctx(&context);
+ 	}
+ 
+ 	return audit_buf;
 diff --git a/security/security.c b/security/security.c
-index 862f0bc2f114..ddbaf2073b02 100644
+index c3c9bd88b7af..2b355c2a53f3 100644
 --- a/security/security.c
 +++ b/security/security.c
-@@ -2263,9 +2263,18 @@ int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
- }
- EXPORT_SYMBOL(security_inode_setsecctx);
- 
--int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
-+int security_inode_getsecctx(struct inode *inode, struct lsmcontext *cp)
- {
--	return call_int_hook(inode_getsecctx, -EOPNOTSUPP, inode, ctx, ctxlen);
-+	struct security_hook_list *hp;
+@@ -2135,17 +2135,23 @@ int security_secctx_to_secid(const char *secdata, u32 seclen,
+ }
+ EXPORT_SYMBOL(security_secctx_to_secid);
+ 
+-void security_release_secctx(char *secdata, u32 seclen)
++void security_release_secctx(struct lsmcontext *cp)
+ {
+ 	struct security_hook_list *hp;
+-	int *display = current->security;
++	bool found = false;
+ 
+ 	hlist_for_each_entry(hp, &security_hook_heads.release_secctx, list)
+-		if (display == NULL || *display == LSMBLOB_INVALID ||
+-		    *display == hp->lsmid->slot) {
+-			hp->hook.release_secctx(secdata, seclen);
+-			return;
++		if (cp->slot == hp->lsmid->slot) {
++			hp->hook.release_secctx(cp->context, cp->len);
++			found = true;
++			break;
+ 		}
 +
 +	memset(cp, 0, sizeof(*cp));
 +
-+	hlist_for_each_entry(hp, &security_hook_heads.inode_getsecctx, list) {
-+		cp->slot = hp->lsmid->slot;
-+		return hp->hook.inode_getsecctx(inode, (void **)&cp->context,
-+						&cp->len);
-+	}
-+	return -EOPNOTSUPP;
- }
- EXPORT_SYMBOL(security_inode_getsecctx);
- 
++	if (!found)
++		pr_warn("%s context \"%s\" from slot %d not released\n",
++			__func__, cp->context, cp->slot);
+ }
+ EXPORT_SYMBOL(security_release_secctx);
+ 
+diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
+index 7a0ead4da479..472cb2097d36 100644
+--- a/security/smack/smack_lsm.c
++++ b/security/smack/smack_lsm.c
+@@ -4439,11 +4439,16 @@ static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
+ 	return 0;
+ }
+ 
+-/*
+- * There used to be a smack_release_secctx hook
+- * that did nothing back when hooks were in a vector.
+- * Now that there's a list such a hook adds cost.
++/**
++ * smack_release_secctx - do everything necessary to free a context
++ * @secdata: Unused
++ * @seclen: Unused
++ *
++ * Do nothing but hold a slot in the hooks list.
+  */
++static void smack_release_secctx(char *secdata, u32 seclen)
++{
++}
+ 
+ static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
+ {
+@@ -4688,6 +4693,7 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
+ 	LSM_HOOK_INIT(ismaclabel, smack_ismaclabel),
+ 	LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx),
+ 	LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid),
++	LSM_HOOK_INIT(release_secctx, smack_release_secctx),
+ 	LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx),
+ 	LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx),
+ 	LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx),
 -- 
-2.24.1
+2.20.1
 
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