--- v8
+++ v26
@@ -1,326 +1,566 @@
-Create a new entry "display" in /proc/.../attr for controlling
-which LSM security information is displayed for a process.
-The name of an active LSM that supplies hooks for human readable
-data may be written to "display" to set the value. This requires
-CAP_MAC_ADMIN privilege. The name of the LSM currently in use can
-be read from "display". At this point there can only be one LSM
-capable of display active. A helper function lsm_task_display()
-is provided to get the display slot for a task_struct.
+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.
-Note that procfs restricts writes in the attr directory to 'self'.
+Reviewed-by: Kees Cook <keescook@chromium.org>
+Reviewed-by: John Johansen <john.johansen@canonical.com>
+Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
+Acked-by: Chuck Lever <chuck.lever@oracle.com>
+Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
+Cc: linux-integrity@vger.kernel.org
+Cc: netdev@vger.kernel.org
+Cc: linux-audit@redhat.com
+Cc: netfilter-devel@vger.kernel.org
+To: Pablo Neira Ayuso <pablo@netfilter.org>
+Cc: linux-nfs@vger.kernel.org
+---
+ drivers/android/binder.c | 10 ++++---
+ fs/ceph/xattr.c | 6 ++++-
+ fs/nfs/nfs4proc.c | 8 ++++--
+ fs/nfsd/nfs4xdr.c | 7 +++--
+ include/linux/security.h | 35 +++++++++++++++++++++++--
+ 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 | 11 ++++----
+ 15 files changed, 121 insertions(+), 35 deletions(-)
-Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
----
- fs/proc/base.c | 1 +
- include/linux/lsm_hooks.h | 15 ++++
- security/security.c | 148 +++++++++++++++++++++++++++++++++-----
- 3 files changed, 147 insertions(+), 17 deletions(-)
-
-diff --git a/fs/proc/base.c b/fs/proc/base.c
-index ddef482f1334..7bf70e041315 100644
---- a/fs/proc/base.c
-+++ b/fs/proc/base.c
-@@ -2618,6 +2618,7 @@ static const struct pid_entry attr_dir_stuff[] = {
- ATTR(NULL, "fscreate", 0666),
- ATTR(NULL, "keycreate", 0666),
- ATTR(NULL, "sockcreate", 0666),
-+ ATTR(NULL, "display", 0666),
- #ifdef CONFIG_SECURITY_SMACK
- DIR("smack", 0555,
- proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops),
-diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
-index fe1fb7a69ee5..33e5ab4af9f8 100644
---- a/include/linux/lsm_hooks.h
-+++ b/include/linux/lsm_hooks.h
-@@ -2134,4 +2134,19 @@ static inline void security_delete_hooks(struct security_hook_list *hooks,
-
- extern int lsm_inode_alloc(struct inode *inode);
-
+diff --git a/drivers/android/binder.c b/drivers/android/binder.c
+index ab55358f868b..eca789340ef6 100644
+--- a/drivers/android/binder.c
++++ b/drivers/android/binder.c
+@@ -2461,6 +2461,7 @@ 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;
+@@ -2772,7 +2773,8 @@ static void binder_transaction(struct binder_proc *proc,
+ t->security_ctx = 0;
+ WARN_ON(1);
+ }
+- 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;
+@@ -3114,8 +3116,10 @@ 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)
+- 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/ceph/xattr.c b/fs/ceph/xattr.c
+index 1242db8d3444..b867089e1aa4 100644
+--- a/fs/ceph/xattr.c
++++ b/fs/ceph/xattr.c
+@@ -1356,12 +1356,16 @@ int ceph_security_init_secctx(struct dentry *dentry, umode_t mode,
+
+ void ceph_release_acl_sec_ctx(struct ceph_acl_sec_ctx *as_ctx)
+ {
++#ifdef CONFIG_CEPH_FS_SECURITY_LABEL
++ struct lsmcontext scaff; /* scaffolding */
++#endif
+ #ifdef CONFIG_CEPH_FS_POSIX_ACL
+ posix_acl_release(as_ctx->acl);
+ posix_acl_release(as_ctx->default_acl);
+ #endif
+ #ifdef CONFIG_CEPH_FS_SECURITY_LABEL
+- security_release_secctx(as_ctx->sec_ctx, as_ctx->sec_ctxlen);
++ lsmcontext_init(&scaff, as_ctx->sec_ctx, as_ctx->sec_ctxlen, 0);
++ security_release_secctx(&scaff);
+ #endif
+ if (as_ctx->pagelist)
+ ceph_pagelist_release(as_ctx->pagelist);
+diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
+index 87d04f2c9385..a179d70eeb7e 100644
+--- a/fs/nfs/nfs4proc.c
++++ b/fs/nfs/nfs4proc.c
+@@ -136,8 +136,12 @@ 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 7abeccb975b2..089ec4b61ef1 100644
+--- a/fs/nfsd/nfs4xdr.c
++++ b/fs/nfsd/nfs4xdr.c
+@@ -2844,6 +2844,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
+ int err;
+ struct nfs4_acl *acl = NULL;
+ #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
++ struct lsmcontext scaff; /* scaffolding */
+ void *context = NULL;
+ int contextlen;
+ #endif
+@@ -3345,8 +3346,10 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
+
+ out:
+ #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
+- 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 c1c31eb23859..3b2ffef65b05 100644
+--- a/include/linux/security.h
++++ b/include/linux/security.h
+@@ -133,6 +133,37 @@ enum lockdown_reason {
+
+ extern const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX+1];
+
++/*
++ * 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 */
++};
++
+/**
-+ * lsm_task_display - the "display LSM for this task
-+ * @task: The task to report on
++ * 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
+ *
-+ * Returns the task's display LSM slot.
++ * Fill in the lsmcontext from the provided information.
++ * This is a scaffolding function that will be removed when
++ * lsmcontext integration is complete.
+ */
-+static inline int lsm_task_display(struct task_struct *task)
++static inline void lsmcontext_init(struct lsmcontext *cp, char *context,
++ u32 size, int slot)
+{
-+ int *display = task->security;
-+
-+ if (display)
-+ return *display;
-+ return LSMBLOB_INVALID;
++ cp->slot = slot;
++ cp->context = context;
++ cp->len = size;
+}
+
- #endif /* ! __LINUX_LSM_HOOKS_H */
+ /*
+ * Data exported by the security modules
+ *
+@@ -550,7 +581,7 @@ 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);
+@@ -1414,7 +1445,7 @@ static inline int security_secctx_to_secid(const char *secdata,
+ 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 23a35ff1b3f2..f273c4d777ec 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;
+ struct lsmblob lb;
+ char *secdata;
+ u32 seclen;
+@@ -106,7 +107,9 @@ 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 8ec64e6e8bc0..c17ec23158c4 100644
+--- a/kernel/audit.c
++++ b/kernel/audit.c
+@@ -1192,6 +1192,7 @@ 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)
+@@ -1449,15 +1450,18 @@ 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);
+@@ -2132,6 +2136,7 @@ int audit_log_task_context(struct audit_buffer *ab)
+ unsigned len;
+ int error;
+ struct lsmblob blob;
++ struct lsmcontext scaff; /* scaffolding */
+
+ security_task_getsecid_subj(current, &blob);
+ if (!lsmblob_is_set(&blob))
+@@ -2145,7 +2150,8 @@ 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 573c6a8e505f..3fb9d3639123 100644
+--- a/kernel/auditsc.c
++++ b/kernel/auditsc.c
+@@ -996,6 +996,7 @@ 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;
+@@ -1013,7 +1014,8 @@ 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=");
+@@ -1226,6 +1228,7 @@ 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;
+
+@@ -1259,7 +1262,8 @@ 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) {
+@@ -1408,6 +1412,7 @@ 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)) {
+@@ -1416,7 +1421,8 @@ 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 2f089733ada7..a7e4c1b34b6c 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, secid;
+@@ -145,7 +146,8 @@ 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 caf3ecb5a66b..914ab6a96573 100644
+--- a/net/netfilter/nf_conntrack_netlink.c
++++ b/net/netfilter/nf_conntrack_netlink.c
+@@ -339,6 +339,7 @@ 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() puts ct->secmark into all of the secids in blob.
+ * security_secid_to_secctx() will know which security module
+@@ -359,7 +360,8 @@ 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 b02afa0a1516..b039445f3efc 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 bdbb0b60bf7b..06b7751c7668 100644
+--- a/net/netfilter/nfnetlink_queue.c
++++ b/net/netfilter/nfnetlink_queue.c
+@@ -397,6 +397,7 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
+ enum ip_conntrack_info ctinfo;
+ struct nfnl_ct_hook *nfnl_ct;
+ bool csum_verify;
++ struct lsmcontext scaff; /* scaffolding */
+ char *secdata = NULL;
+ u32 seclen = 0;
+
+@@ -626,8 +627,10 @@ 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:
+@@ -635,8 +638,10 @@ 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 b08442582874..8ca1e2b33dcf 100644
+--- a/net/netlabel/netlabel_unlabeled.c
++++ b/net/netlabel/netlabel_unlabeled.c
+@@ -374,6 +374,7 @@ 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;
+@@ -447,7 +448,9 @@ 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);
+@@ -478,6 +481,7 @@ 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;
+@@ -509,7 +513,9 @@ 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);
+@@ -546,6 +552,7 @@ 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;
+@@ -576,7 +583,8 @@ 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);
+@@ -1095,6 +1103,7 @@ 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;
+@@ -1165,7 +1174,9 @@ 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 893301ae0131..ef139d8ae7cd 100644
+--- a/net/netlabel/netlabel_user.c
++++ b/net/netlabel/netlabel_user.c
+@@ -84,6 +84,7 @@ 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;
+@@ -103,7 +104,8 @@ 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 8927508b2142..c3c9bd88b7af 100644
+index 1ce125c01782..f6a33bf2a7fc 100644
--- a/security/security.c
+++ b/security/security.c
-@@ -31,6 +31,7 @@
- #include <linux/backing-dev.h>
- #include <linux/string.h>
- #include <linux/msg.h>
-+#include <linux/binfmts.h>
- #include <net/flow.h>
- #include <net/sock.h>
-
-@@ -46,7 +47,14 @@ static struct kmem_cache *lsm_file_cache;
- static struct kmem_cache *lsm_inode_cache;
-
- char *lsm_names;
--static struct lsm_blob_sizes blob_sizes __lsm_ro_after_init;
+@@ -2359,16 +2359,17 @@ 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 ilsm = lsm_task_ilsm(current);
+
+ hlist_for_each_entry(hp, &security_hook_heads.release_secctx, list)
+- if (ilsm == LSMBLOB_INVALID || ilsm == hp->lsmid->slot) {
+- hp->hook.release_secctx(secdata, seclen);
+- return;
++ if (cp->slot == hp->lsmid->slot) {
++ hp->hook.release_secctx(cp->context, cp->len);
++ break;
+ }
+
-+/*
-+ * The task blob includes the "display" slot used for
-+ * chosing which module presents contexts.
-+ */
-+static struct lsm_blob_sizes blob_sizes __lsm_ro_after_init = {
-+ .lbs_task = sizeof(int),
-+};
-
- /* Boot-time LSM user choice */
- static __initdata const char *chosen_lsm_order;
-@@ -423,8 +431,10 @@ static int lsm_append(const char *new, char **result)
-
- /*
- * Current index to use while initializing the lsmblob secid list.
-+ * Pointers to the LSM id structures for local use.
- */
- static int lsm_slot __lsm_ro_after_init;
-+static struct lsm_id *lsm_slotlist[LSMBLOB_ENTRIES];
-
- /**
- * security_add_hooks - Add a modules hooks to the hook lists.
-@@ -444,6 +454,7 @@ void __init security_add_hooks(struct security_hook_list *hooks, int count,
- if (lsmid->slot == LSMBLOB_NEEDED) {
- if (lsm_slot >= LSMBLOB_ENTRIES)
- panic("%s Too many LSMs registered.\n", __func__);
-+ lsm_slotlist[lsm_slot] = lsmid;
- lsmid->slot = lsm_slot++;
- init_debug("%s assigned lsmblob slot %d\n", lsmid->lsm,
- lsmid->slot);
-@@ -564,6 +575,8 @@ int lsm_inode_alloc(struct inode *inode)
- */
- static int lsm_task_alloc(struct task_struct *task)
- {
-+ int *display;
-+
- if (blob_sizes.lbs_task == 0) {
- task->security = NULL;
- return 0;
-@@ -572,6 +585,15 @@ static int lsm_task_alloc(struct task_struct *task)
- task->security = kzalloc(blob_sizes.lbs_task, GFP_KERNEL);
- if (task->security == NULL)
- return -ENOMEM;
-+
-+ /*
-+ * The start of the task blob contains the "display" LSM slot number.
-+ * Start with it set to the invalid slot number, indicating that the
-+ * default first registered LSM be displayed.
-+ */
-+ display = task->security;
-+ *display = LSMBLOB_INVALID;
-+
- return 0;
- }
-
-@@ -1563,14 +1585,26 @@ int security_file_open(struct file *file)
-
- int security_task_alloc(struct task_struct *task, unsigned long clone_flags)
- {
-+ int *odisplay = current->security;
-+ int *ndisplay;
- int rc = lsm_task_alloc(task);
-
-- if (rc)
-+ if (unlikely(rc))
- return rc;
-+
- rc = call_int_hook(task_alloc, 0, task, clone_flags);
-- if (unlikely(rc))
-+ if (unlikely(rc)) {
- security_task_free(task);
-- return rc;
-+ return rc;
-+ }
-+
-+ if (odisplay) {
-+ ndisplay = task->security;
-+ if (ndisplay)
-+ *ndisplay = *odisplay;
-+ }
-+
-+ return 0;
- }
-
- void security_task_free(struct task_struct *task)
-@@ -1967,23 +2001,89 @@ int security_getprocattr(struct task_struct *p, const char *lsm, char *name,
- char **value)
- {
- struct security_hook_list *hp;
-+ int display = lsm_task_display(current);
-+ int slot = 0;
-+
-+ if (!strcmp(name, "display")) {
-+ /*
-+ * lsm_slot will be 0 if there are no displaying modules.
-+ */
-+ if (lsm_slot == 0)
-+ return -EINVAL;
-+ if (display != LSMBLOB_INVALID)
-+ slot = display;
-+ *value = kstrdup(lsm_slotlist[slot]->lsm, GFP_KERNEL);
-+ if (*value)
-+ return strlen(*value);
-+ return -ENOMEM;
-+ }
-
- hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) {
- if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm))
- continue;
-+ if (lsm == NULL && display != LSMBLOB_INVALID &&
-+ display != hp->lsmid->slot)
-+ continue;
- return hp->hook.getprocattr(p, name, value);
- }
- return -EINVAL;
- }
-
-+/**
-+ * security_setprocattr - Set process attributes via /proc
-+ * @lsm: name of module involved, or NULL
-+ * @name: name of the attribute
-+ * @value: value to set the attribute to
-+ * @size: size of the value
-+ *
-+ * Set the process attribute for the specified security module
-+ * to the specified value. Note that this can only be used to set
-+ * the process attributes for the current, or "self" process.
-+ * The /proc code has already done this check.
-+ *
-+ * Returns 0 on success, an appropriate code otherwise.
-+ */
- int security_setprocattr(const char *lsm, const char *name, void *value,
- size_t size)
- {
- struct security_hook_list *hp;
-+ char *term;
-+ char *cp;
-+ int *display = current->security;
-+ int rc = -EINVAL;
-+ int slot = 0;
-+
-+ if (!strcmp(name, "display")) {
-+ if (!capable(CAP_MAC_ADMIN))
-+ return -EPERM;
-+ /*
-+ * lsm_slot will be 0 if there are no displaying modules.
-+ */
-+ if (lsm_slot == 0 || size == 0)
-+ return -EINVAL;
-+ term = kmemdup_nul(value, size, GFP_KERNEL);
-+ if (term == NULL)
-+ return -ENOMEM;
-+
-+ cp = strsep(&term, " \n");
-+
-+ for (slot = 0; slot < lsm_slot; slot++)
-+ if (!strcmp(cp, lsm_slotlist[slot]->lsm)) {
-+ *display = lsm_slotlist[slot]->slot;
-+ rc = size;
-+ break;
-+ }
-+
-+ kfree(cp);
-+ return rc;
-+ }
-
- hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) {
- if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm))
- continue;
-+ if (lsm == NULL && *display != LSMBLOB_INVALID &&
-+ *display != hp->lsmid->slot)
-+ continue;
- return hp->hook.setprocattr(name, value, size);
- }
- return -EINVAL;
-@@ -2003,15 +2103,15 @@ EXPORT_SYMBOL(security_ismaclabel);
- int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen)
- {
- struct security_hook_list *hp;
-- int rc;
-+ int display = lsm_task_display(current);
-
- 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;
-- rc = hp->hook.secid_to_secctx(blob->secid[hp->lsmid->slot],
-- secdata, seclen);
-- if (rc != 0)
-- return rc;
-+ if (display == LSMBLOB_INVALID || display == hp->lsmid->slot)
-+ return hp->hook.secid_to_secctx(
-+ blob->secid[hp->lsmid->slot],
-+ secdata, seclen);
- }
- return 0;
- }
-@@ -2021,16 +2121,15 @@ int security_secctx_to_secid(const char *secdata, u32 seclen,
- struct lsmblob *blob)
- {
- struct security_hook_list *hp;
-- int rc;
-+ int display = lsm_task_display(current);
-
- lsmblob_init(blob, 0);
- hlist_for_each_entry(hp, &security_hook_heads.secctx_to_secid, list) {
- if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
- continue;
-- rc = hp->hook.secctx_to_secid(secdata, seclen,
-- &blob->secid[hp->lsmid->slot]);
-- if (rc != 0)
-- return rc;
-+ if (display == LSMBLOB_INVALID || display == hp->lsmid->slot)
-+ return hp->hook.secctx_to_secid(secdata, seclen,
-+ &blob->secid[hp->lsmid->slot]);
- }
- return 0;
- }
-@@ -2038,7 +2137,15 @@ EXPORT_SYMBOL(security_secctx_to_secid);
-
- void security_release_secctx(char *secdata, u32 seclen)
- {
-- call_void_hook(release_secctx, secdata, seclen);
-+ struct security_hook_list *hp;
-+ int *display = current->security;
-+
-+ 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;
-+ }
++ memset(cp, 0, sizeof(*cp));
}
EXPORT_SYMBOL(security_release_secctx);
-@@ -2163,8 +2270,15 @@ EXPORT_SYMBOL(security_sock_rcv_skb);
- int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
- int __user *optlen, unsigned len)
- {
-- return call_int_hook(socket_getpeersec_stream, -ENOPROTOOPT, sock,
-- optval, optlen, len);
-+ int display = lsm_task_display(current);
-+ struct security_hook_list *hp;
-+
-+ hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_stream,
-+ list)
-+ if (display == LSMBLOB_INVALID || display == hp->lsmid->slot)
-+ return hp->hook.socket_getpeersec_stream(sock, optval,
-+ optlen, len);
-+ return -ENOPROTOOPT;
- }
-
- int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
--
-2.20.1
+2.29.2