On 7/24/20 1:32 PM, Casey Schaufler wrote:
 Replace the (secctx,seclen) pointer pair with a single
 lsmcontext pointer to allow return of the LSM identifier
 along with the context and context length. This allows
 security_release_secctx() to know how to release the
 context. Callers have been modified to use or save the
 returned data from the new structure.
 
 Reviewed-by: Kees Cook <keescook(a)chromium.org>
 Acked-by: Stephen Smalley <sds(a)tycho.nsa.gov>
 Acked-by: Paul Moore <paul(a)paul-moore.com>
 Signed-off-by: Casey Schaufler <casey(a)schaufler-ca.com>
 Cc: netdev(a)vger.kernel.org
 ---
  drivers/android/binder.c                | 26 +++++++---------
  include/linux/security.h                |  4 +--
  include/net/scm.h                       | 10 ++-----
  kernel/audit.c                          | 35 ++++++++--------------
  kernel/auditsc.c                        | 31 +++++++------------
  net/ipv4/ip_sockglue.c                  |  7 ++---
  net/netfilter/nf_conntrack_netlink.c    | 18 +++++------
  net/netfilter/nf_conntrack_standalone.c |  7 ++---
  net/netfilter/nfnetlink_queue.c         |  5 +++-
  net/netlabel/netlabel_unlabeled.c       | 40 ++++++++-----------------
  net/netlabel/netlabel_user.c            |  7 ++---
  security/security.c                     | 10 +++++--
  12 files changed, 76 insertions(+), 124 deletions(-)
 
 diff --git a/drivers/android/binder.c b/drivers/android/binder.c
 index b7ab206f8bb3..ceb5987c7d76 100644
 --- a/drivers/android/binder.c
 +++ b/drivers/android/binder.c
 @@ -2861,9 +2861,7 @@ static void binder_transaction(struct binder_proc *proc,
  	binder_size_t last_fixup_min_off = 0;
  	struct binder_context *context = proc->context;
  	int t_debug_id = atomic_inc_return(&binder_last_id);
 -	char *secctx = NULL;
 -	u32 secctx_sz = 0;
 -	struct lsmcontext scaff; /* scaffolding */
 +	struct lsmcontext lsmctx = { };
  
  	e = binder_transaction_log_add(&binder_transaction_log);
  	e->debug_id = t_debug_id;
 @@ -3111,14 +3109,14 @@ static void binder_transaction(struct binder_proc *proc,
  		size_t added_size;
  
  		security_task_getsecid(proc->tsk, &blob);
 -		ret = security_secid_to_secctx(&blob, &secctx, &secctx_sz);
 +		ret = security_secid_to_secctx(&blob, &lsmctx);
  		if (ret) {
  			return_error = BR_FAILED_REPLY;
  			return_error_param = ret;
  			return_error_line = __LINE__;
  			goto err_get_secctx_failed;
  		}
 -		added_size = ALIGN(secctx_sz, sizeof(u64));
 +		added_size = ALIGN(lsmctx.len, sizeof(u64));
  		extra_buffers_size += added_size;
  		if (extra_buffers_size < added_size) {
  			/* integer overflow of extra_buffers_size */
 @@ -3145,24 +3143,22 @@ static void binder_transaction(struct binder_proc *proc,
  		t->buffer = NULL;
  		goto err_binder_alloc_buf_failed;
  	}
 -	if (secctx) {
 +	if (lsmctx.context) {
  		int err;
  		size_t buf_offset = ALIGN(tr->data_size, sizeof(void *)) +
  				    ALIGN(tr->offsets_size, sizeof(void *)) +
  				    ALIGN(extra_buffers_size, sizeof(void *)) -
 -				    ALIGN(secctx_sz, sizeof(u64));
 +				    ALIGN(lsmctx.len, sizeof(u64));
  
  		t->security_ctx = (uintptr_t)t->buffer->user_data + buf_offset;
  		err = binder_alloc_copy_to_buffer(&target_proc->alloc,
  						  t->buffer, buf_offset,
 -						  secctx, secctx_sz);
 +						  lsmctx.context, lsmctx.len);
  		if (err) {
  			t->security_ctx = 0;
  			WARN_ON(1);
  		}
 -		lsmcontext_init(&scaff, secctx, secctx_sz, 0);
 -		security_release_secctx(&scaff);
 -		secctx = NULL;
 +		security_release_secctx(&lsmctx);
  	}
  	t->buffer->debug_id = t->debug_id;
  	t->buffer->transaction = t;
 @@ -3218,7 +3214,7 @@ static void binder_transaction(struct binder_proc *proc,
  	off_end_offset = off_start_offset + tr->offsets_size;
  	sg_buf_offset = ALIGN(off_end_offset, sizeof(void *));
  	sg_buf_end_offset = sg_buf_offset + extra_buffers_size -
 -		ALIGN(secctx_sz, sizeof(u64));
 +		ALIGN(lsmctx.len, sizeof(u64));
  	off_min = 0;
  	for (buffer_offset = off_start_offset; buffer_offset < off_end_offset;
  	     buffer_offset += sizeof(binder_size_t)) {
 @@ -3494,10 +3490,8 @@ static void binder_transaction(struct binder_proc *proc,
  	binder_alloc_free_buf(&target_proc->alloc, t->buffer);
  err_binder_alloc_buf_failed:
  err_bad_extra_size:
 -	if (secctx) {
 -		lsmcontext_init(&scaff, secctx, secctx_sz, 0);
 -		security_release_secctx(&scaff);
 -	}
 +	if (lsmctx.context)
 +		security_release_secctx(&lsmctx);
  err_get_secctx_failed:
  	kfree(tcomplete);
  	binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
 diff --git a/include/linux/security.h b/include/linux/security.h
 index f67e4084b893..43f8a2660d37 100644
 --- a/include/linux/security.h
 +++ b/include/linux/security.h
 @@ -553,7 +553,7 @@ int security_setprocattr(const char *lsm, const char *name, void
*value,
  			 size_t size);
  int security_netlink_send(struct sock *sk, struct sk_buff *skb);
  int security_ismaclabel(const char *name);
 -int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen);
 +int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp);
  int security_secctx_to_secid(const char *secdata, u32 seclen,
  			     struct lsmblob *blob);
  void security_release_secctx(struct lsmcontext *cp);
 @@ -1371,7 +1371,7 @@ static inline int security_ismaclabel(const char *name)
  }
  
  static inline int security_secid_to_secctx(struct lsmblob *blob,
 -					   char **secdata, u32 *seclen)
 +					   struct lsmcontext *cp)
  {
  	return -EOPNOTSUPP;
  }
 diff --git a/include/net/scm.h b/include/net/scm.h
 index 30ba801c91bd..4a6ad8caf423 100644
 --- a/include/net/scm.h
 +++ b/include/net/scm.h
 @@ -93,18 +93,14 @@ static __inline__ int scm_send(struct socket *sock, struct msghdr
*msg,
  static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie
*scm)
  {
  	struct lsmcontext context;
 -	char *secdata;
 -	u32 seclen;
  	int err;
  
  	if (test_bit(SOCK_PASSSEC, &sock->flags)) {
 -		err = security_secid_to_secctx(&scm->lsmblob, &secdata,
 -					       &seclen);
 +		err = security_secid_to_secctx(&scm->lsmblob, &context);
  
  		if (!err) {
 -			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
 -			/*scaffolding*/
 -			lsmcontext_init(&context, secdata, seclen, 0);
 +			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY,
 +				 context.len, context.context);
  			security_release_secctx(&context);
  		}
  	}
 diff --git a/kernel/audit.c b/kernel/audit.c
 index 3378c773b1c1..d300e41ca443 100644
 --- a/kernel/audit.c
 +++ b/kernel/audit.c
 @@ -1186,9 +1186,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr
*nlh)
  	struct audit_buffer	*ab;
  	u16			msg_type = nlh->nlmsg_type;
  	struct audit_sig_info   *sig_data;
 -	char			*ctx = NULL;
 -	u32			len;
 -	struct lsmcontext	scaff; /* scaffolding */
 +	struct lsmcontext	context = { };
  
  	err = audit_netlink_ok(skb, msg_type);
  	if (err)
 @@ -1430,30 +1428,26 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr
*nlh)
  		break;
  	}
  	case AUDIT_SIGNAL_INFO:
 -		len = 0;
  		if (lsmblob_is_set(&audit_sig_lsm)) {
 -			err = security_secid_to_secctx(&audit_sig_lsm, &ctx,
 -						       &len);
 +			err = security_secid_to_secctx(&audit_sig_lsm,
 +						       &context);
  			if (err)
  				return err;
  		}
 -		sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
 +		sig_data = kmalloc(sizeof(*sig_data) + context.len, GFP_KERNEL);
  		if (!sig_data) {
 -			if (lsmblob_is_set(&audit_sig_lsm)) {
 -				lsmcontext_init(&scaff, ctx, len, 0);
 -				security_release_secctx(&scaff);
 -			}
 +			if (lsmblob_is_set(&audit_sig_lsm))
 +				security_release_secctx(&context);
  			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);
 -			lsmcontext_init(&scaff, ctx, len, 0);
 -			security_release_secctx(&scaff);
 +			memcpy(sig_data->ctx, context.context, context.len);
 +			security_release_secctx(&context);
  		}
  		audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0,
 -				 sig_data, sizeof(*sig_data) + len);
 +				 sig_data, sizeof(*sig_data) + context.len); 
use after "free", move the security_release_secctx(&context) to after here
  		kfree(sig_data);
  		break;
  	case AUDIT_TTY_GET: {
 @@ -2116,26 +2110,23 @@ void audit_log_key(struct audit_buffer *ab, char *key)
  
  int audit_log_task_context(struct audit_buffer *ab)
  {
 -	char *ctx = NULL;
 -	unsigned len;
  	int error;
  	struct lsmblob blob;
 -	struct lsmcontext scaff; /* scaffolding */
 +	struct lsmcontext context;
  
  	security_task_getsecid(current, &blob);
  	if (!lsmblob_is_set(&blob))
  		return 0;
  
 -	error = security_secid_to_secctx(&blob, &ctx, &len);
 +	error = security_secid_to_secctx(&blob, &context);
  	if (error) {
  		if (error != -EINVAL)
  			goto error_path;
  		return 0;
  	}
  
 -	audit_log_format(ab, " subj=%s", ctx);
 -	lsmcontext_init(&scaff, ctx, len, 0);
 -	security_release_secctx(&scaff);
 +	audit_log_format(ab, " subj=%s", context.context);
 +	security_release_secctx(&context);
  	return 0;
  
  error_path:
 diff --git a/kernel/auditsc.c b/kernel/auditsc.c
 index ac6836c1f2d3..1f7bd6b34ec7 100644
 --- a/kernel/auditsc.c
 +++ b/kernel/auditsc.c
 @@ -980,9 +980,7 @@ 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;
 +	struct lsmcontext lsmctx;
  	int rc = 0;
  
  	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
 @@ -993,13 +991,12 @@ static int audit_log_pid_context(struct audit_context *context,
pid_t pid,
  			 from_kuid(&init_user_ns, auid),
  			 from_kuid(&init_user_ns, uid), sessionid);
  	if (lsmblob_is_set(blob)) {
 -		if (security_secid_to_secctx(blob, &ctx, &len)) {
 +		if (security_secid_to_secctx(blob, &lsmctx)) {
  			audit_log_format(ab, " obj=(none)");
  			rc = 1;
  		} else {
 -			audit_log_format(ab, " obj=%s", ctx);
 -			lsmcontext_init(&lsmcxt, ctx, len, 0); /*scaffolding*/
 -			security_release_secctx(&lsmcxt);
 +			audit_log_format(ab, " obj=%s", lsmctx.context);
 +			security_release_secctx(&lsmctx);
  		}
  	}
  	audit_log_format(ab, " ocomm=");
 @@ -1212,7 +1209,6 @@ 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;
  
 @@ -1236,17 +1232,15 @@ static void show_special(struct audit_context *context, int
*call_panic)
  				 from_kgid(&init_user_ns, context->ipc.gid),
  				 context->ipc.mode);
  		if (osid) {
 -			char *ctx = NULL;
 -			u32 len;
 +			struct lsmcontext lsmcxt;
  			struct lsmblob blob;
  
  			lsmblob_init(&blob, osid);
 -			if (security_secid_to_secctx(&blob, &ctx, &len)) {
 +			if (security_secid_to_secctx(&blob, &lsmcxt)) {
  				audit_log_format(ab, " osid=%u", osid);
  				*call_panic = 1;
  			} else {
 -				audit_log_format(ab, " obj=%s", ctx);
 -				lsmcontext_init(&lsmcxt, ctx, len, 0);
 +				audit_log_format(ab, " obj=%s", lsmcxt.context);
  				security_release_secctx(&lsmcxt);
  			}
  		}
 @@ -1390,20 +1384,17 @@ static void audit_log_name(struct audit_context *context, struct
audit_names *n,
  				 MAJOR(n->rdev),
  				 MINOR(n->rdev));
  	if (n->osid != 0) {
 -		char *ctx = NULL;
 -		u32 len;
  		struct lsmblob blob;
 -		struct lsmcontext lsmcxt;
 +		struct lsmcontext lsmctx;
  
  		lsmblob_init(&blob, n->osid);
 -		if (security_secid_to_secctx(&blob, &ctx, &len)) {
 +		if (security_secid_to_secctx(&blob, &lsmctx)) {
  			audit_log_format(ab, " osid=%u", n->osid);
  			if (call_panic)
  				*call_panic = 2;
  		} else {
 -			audit_log_format(ab, " obj=%s", ctx);
 -			lsmcontext_init(&lsmcxt, ctx, len, 0); /* scaffolding */
 -			security_release_secctx(&lsmcxt);
 +			audit_log_format(ab, " obj=%s", lsmctx.context);
 +			security_release_secctx(&lsmctx);
  		}
  	}
  
 diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
 index 6391a570f9ad..176ac9ce6069 100644
 --- a/net/ipv4/ip_sockglue.c
 +++ b/net/ipv4/ip_sockglue.c
 @@ -132,20 +132,17 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct
sk_buff *skb)
  {
  	struct lsmcontext context;
  	struct lsmblob lb;
 -	char *secdata;
 -	u32 seclen;
  	int err;
  
  	err = security_socket_getpeersec_dgram(NULL, skb, &lb);
  	if (err)
  		return;
  
 -	err = security_secid_to_secctx(&lb, &secdata, &seclen);
 +	err = security_secid_to_secctx(&lb, &context);
  	if (err)
  		return;
  
 -	put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
 -	lsmcontext_init(&context, secdata, seclen, 0); /* scaffolding */
 +	put_cmsg(msg, SOL_IP, SCM_SECURITY, context.len, context.context);
  	security_release_secctx(&context);
  }
  
 diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
 index 1c45ca8c3c21..e38b5182e301 100644
 --- a/net/netfilter/nf_conntrack_netlink.c
 +++ b/net/netfilter/nf_conntrack_netlink.c
 @@ -331,8 +331,7 @@ static int ctnetlink_dump_mark(struct sk_buff *skb, const struct
nf_conn *ct)
  static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
  {
  	struct nlattr *nest_secctx;
 -	int len, ret;
 -	char *secctx;
 +	int ret;
  	struct lsmblob blob;
  	struct lsmcontext context;
  
 @@ -340,7 +339,7 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct
nf_conn *ct)
  	 * security_secid_to_secctx() will know which security module
  	 * to use to create the secctx.  */
  	lsmblob_init(&blob, ct->secmark);
 -	ret = security_secid_to_secctx(&blob, &secctx, &len);
 +	ret = security_secid_to_secctx(&blob, &context);
  	if (ret)
  		return 0;
  
 @@ -349,13 +348,12 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct
nf_conn *ct)
  	if (!nest_secctx)
  		goto nla_put_failure;
  
 -	if (nla_put_string(skb, CTA_SECCTX_NAME, secctx))
 +	if (nla_put_string(skb, CTA_SECCTX_NAME, context.context))
  		goto nla_put_failure;
  	nla_nest_end(skb, nest_secctx);
  
  	ret = 0;
  nla_put_failure:
 -	lsmcontext_init(&context, secctx, len, 0); /* scaffolding */
  	security_release_secctx(&context);
  	return ret;
  }
 @@ -655,15 +653,15 @@ static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
  #ifdef CONFIG_NF_CONNTRACK_SECMARK
  	int len, ret;
  	struct lsmblob blob;
 +	struct lsmcontext context;
  
 -	/* lsmblob_init() puts ct->secmark into all of the secids in blob.
 -	 * security_secid_to_secctx() will know which security module
 -	 * to use to create the secctx.  */
 -	lsmblob_init(&blob, ct->secmark);
 -	ret = security_secid_to_secctx(&blob, NULL, &len);
 +	ret = security_secid_to_secctx(&blob, &context);
  	if (ret)
  		return 0;
  
 +	len = context.len;
 +	security_release_secctx(&context);
 +
  	return nla_total_size(0) /* CTA_SECCTX */
  	       + nla_total_size(sizeof(char) * len); /* CTA_SECCTX_NAME */
  #else
 diff --git a/net/netfilter/nf_conntrack_standalone.c
b/net/netfilter/nf_conntrack_standalone.c
 index fd01d778c295..0ecd1040f4f1 100644
 --- a/net/netfilter/nf_conntrack_standalone.c
 +++ b/net/netfilter/nf_conntrack_standalone.c
 @@ -173,19 +173,16 @@ static void ct_seq_stop(struct seq_file *s, void *v)
  static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
  {
  	int ret;
 -	u32 len;
 -	char *secctx;
  	struct lsmblob blob;
  	struct lsmcontext context;
  
  	lsmblob_init(&blob, ct->secmark);
 -	ret = security_secid_to_secctx(&blob, &secctx, &len);
 +	ret = security_secid_to_secctx(&blob, &context);
  	if (ret)
  		return;
  
 -	seq_printf(s, "secctx=%s ", secctx);
 +	seq_printf(s, "secctx=%s ", context.context);
  
 -	lsmcontext_init(&context, secctx, len, 0); /* scaffolding */
  	security_release_secctx(&context);
  }
  #else
 diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
 index c89bd87d0dae..fe19ae7216db 100644
 --- a/net/netfilter/nfnetlink_queue.c
 +++ b/net/netfilter/nfnetlink_queue.c
 @@ -306,6 +306,7 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
  	u32 seclen = 0;
  #if IS_ENABLED(CONFIG_NETWORK_SECMARK)
  	struct lsmblob blob;
 +	struct lsmcontext context = { };
  
  	if (!skb || !sk_fullsock(skb->sk))
  		return 0;
 @@ -317,10 +318,12 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char
**secdata)
  		 * blob. security_secid_to_secctx() will know which security
  		 * module to use to create the secctx.  */
  		lsmblob_init(&blob, skb->secmark);
 -		security_secid_to_secctx(&blob, secdata, &seclen);
 +		security_secid_to_secctx(&blob, &context);
 +		*secdata = context.context;
  	}
  
  	read_unlock_bh(&skb->sk->sk_callback_lock);
 +	seclen = context.len;
  #endif
  	return seclen;
  }
 diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
 index 5785e6dcf54b..cf4c56beb3ec 100644
 --- a/net/netlabel/netlabel_unlabeled.c
 +++ b/net/netlabel/netlabel_unlabeled.c
 @@ -375,8 +375,6 @@ int netlbl_unlhsh_add(struct net *net,
  	struct netlbl_unlhsh_iface *iface;
  	struct audit_buffer *audit_buf = NULL;
  	struct lsmcontext context;
 -	char *secctx = NULL;
 -	u32 secctx_len;
  	struct lsmblob blob;
  
  	if (addr_len != sizeof(struct in_addr) &&
 @@ -444,12 +442,9 @@ int netlbl_unlhsh_add(struct net *net,
  		 * security_secid_to_secctx() will know which security module
  		 * to use to create the secctx.  */
  		lsmblob_init(&blob, secid);
 -		if (security_secid_to_secctx(&blob,
 -					     &secctx,
 -					     &secctx_len) == 0) {
 -			audit_log_format(audit_buf, " sec_obj=%s", secctx);
 -			/* scaffolding */
 -			lsmcontext_init(&context, secctx, secctx_len, 0);
 +		if (security_secid_to_secctx(&blob, &context) == 0) {
 +			audit_log_format(audit_buf, " sec_obj=%s",
 +					 context.context);
  			security_release_secctx(&context);
  		}
  		audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
 @@ -482,8 +477,6 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
  	struct audit_buffer *audit_buf;
  	struct net_device *dev;
  	struct lsmcontext context;
 -	char *secctx;
 -	u32 secctx_len;
  	struct lsmblob blob;
  
  	spin_lock(&netlbl_unlhsh_lock);
 @@ -510,11 +503,9 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
  		if (entry != NULL)
  			lsmblob_init(&blob, entry->secid);
  		if (entry != NULL &&
 -		    security_secid_to_secctx(&blob,
 -					     &secctx, &secctx_len) == 0) {
 -			audit_log_format(audit_buf, " sec_obj=%s", secctx);
 -			/* scaffolding */
 -			lsmcontext_init(&context, secctx, secctx_len, 0);
 +		    security_secid_to_secctx(&blob, &context) == 0) {
 +			audit_log_format(audit_buf, " sec_obj=%s",
 +					 context.context);
  			security_release_secctx(&context);
  		}
  		audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
 @@ -553,8 +544,6 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
  	struct audit_buffer *audit_buf;
  	struct net_device *dev;
  	struct lsmcontext context;
 -	char *secctx;
 -	u32 secctx_len;
  	struct lsmblob blob;
  
  	spin_lock(&netlbl_unlhsh_lock);
 @@ -580,10 +569,9 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
  		if (entry != NULL)
  			lsmblob_init(&blob, entry->secid);
  		if (entry != NULL &&
 -		    security_secid_to_secctx(&blob,
 -					     &secctx, &secctx_len) == 0) {
 -			audit_log_format(audit_buf, " sec_obj=%s", secctx);
 -			lsmcontext_init(&context, secctx, secctx_len, 0);
 +		    security_secid_to_secctx(&blob, &context) == 0) {
 +			audit_log_format(audit_buf, " sec_obj=%s",
 +					 context.context);
  			security_release_secctx(&context);
  		}
  		audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
 @@ -1106,8 +1094,6 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
  	struct lsmcontext context;
  	void *data;
  	u32 secid;
 -	char *secctx;
 -	u32 secctx_len;
  	struct lsmblob blob;
  
  	data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
 @@ -1167,15 +1153,13 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
           * security_secid_to_secctx() will know which security module
           * to use to create the secctx.  */
  	lsmblob_init(&blob, secid);
 -	ret_val = security_secid_to_secctx(&blob, &secctx, &secctx_len);
 +	ret_val = security_secid_to_secctx(&blob, &context);
  	if (ret_val != 0)
  		goto list_cb_failure;
  	ret_val = nla_put(cb_arg->skb,
  			  NLBL_UNLABEL_A_SECCTX,
 -			  secctx_len,
 -			  secctx);
 -	/* scaffolding */
 -	lsmcontext_init(&context, secctx, secctx_len, 0);
 +			  context.len,
 +			  context.context);
  	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 ef139d8ae7cd..951ba0639d20 100644
 --- a/net/netlabel/netlabel_user.c
 +++ b/net/netlabel/netlabel_user.c
 @@ -85,8 +85,6 @@ struct audit_buffer *netlbl_audit_start_common(int type,
  {
  	struct audit_buffer *audit_buf;
  	struct lsmcontext context;
 -	char *secctx;
 -	u32 secctx_len;
  	struct lsmblob blob;
  
  	if (audit_enabled == AUDIT_OFF)
 @@ -102,9 +100,8 @@ struct audit_buffer *netlbl_audit_start_common(int type,
  
  	lsmblob_init(&blob, audit_info->secid);
  	if (audit_info->secid != 0 &&
 -	    security_secid_to_secctx(&blob, &secctx, &secctx_len) == 0) {
 -		audit_log_format(audit_buf, " subj=%s", secctx);
 -		lsmcontext_init(&context, secctx, secctx_len, 0);/*scaffolding*/
 +	    security_secid_to_secctx(&blob, &context) == 0) {
 +		audit_log_format(audit_buf, " subj=%s", context.context);
  		security_release_secctx(&context);
  	}
  
 diff --git a/security/security.c b/security/security.c
 index a6d0b6851a66..862f0bc2f114 100644
 --- a/security/security.c
 +++ b/security/security.c
 @@ -2191,18 +2191,22 @@ int security_ismaclabel(const char *name)
  }
  EXPORT_SYMBOL(security_ismaclabel);
  
 -int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen)
 +int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp)
  {
  	struct security_hook_list *hp;
  	int display = lsm_task_display(current);
  
 +	memset(cp, 0, sizeof(*cp));
 +
  	hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) {
  		if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
  			continue;
 -		if (display == LSMBLOB_INVALID || display == hp->lsmid->slot)
 +		if (display == LSMBLOB_INVALID || display == hp->lsmid->slot) {
 +			cp->slot = hp->lsmid->slot;
  			return hp->hook.secid_to_secctx(
  					blob->secid[hp->lsmid->slot],
 -					secdata, seclen);
 +					&cp->context, &cp->len);
 +		}
  	}
  
  	return LSM_RET_DEFAULT(secid_to_secctx);