Audit: use new LSM hooks instead of SELinux exports

Stop using the following exported SELinux interfaces:
selinux_get_inode_sid(inode, sid)
selinux_get_ipc_sid(ipcp, sid)
selinux_get_task_sid(tsk, sid)
selinux_sid_to_string(sid, ctx, len)
kfree(ctx)

and use following generic LSM equivalents respectively:
security_inode_getsecid(inode, secid)
security_ipc_getsecid*(ipcp, secid)
security_task_getsecid(tsk, secid)
security_sid_to_secctx(sid, ctx, len)
security_release_secctx(ctx, len)

Call security_release_secctx only if security_secid_to_secctx
succeeded.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Reviewed-by: Paul Moore <paul.moore@hp.com>

3 files changed, 43 insertions, 37 deletions

diff --git a/kernel/audit.c b/kernel/audit.c
index b782b046543d..784a48e9f382 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -265,13 +265,13 @@ static int audit_log_config_change(char *function_name, int new, int old,
                 char *ctx = NULL;
                 u32 len;
 
-                rc = selinux_sid_to_string(sid, &ctx, &len);
+                rc = security_secid_to_secctx(sid, &ctx, &len);
                 if (rc) {
                         audit_log_format(ab, " sid=%u", sid);
                         allow_changes = 0; /* Something weird, deny request */
                 } else {
                         audit_log_format(ab, " subj=%s", ctx);
-                        kfree(ctx);
+                        security_release_secctx(ctx, len);
                 }
         }
         audit_log_format(ab, " res=%d", allow_changes);
@@ -550,12 +550,13 @@ static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type,
         audit_log_format(*ab, "user pid=%d uid=%u auid=%u",
                          pid, uid, auid);
         if (sid) {
-                rc = selinux_sid_to_string(sid, &ctx, &len);
+                rc = security_secid_to_secctx(sid, &ctx, &len);
                 if (rc)
                         audit_log_format(*ab, " ssid=%u", sid);
-                else
+                else {
                         audit_log_format(*ab, " subj=%s", ctx);
-                kfree(ctx);
+                        security_release_secctx(ctx, len);
+                }
         }
 
         return rc;
@@ -758,18 +759,18 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
                 break;
         }
         case AUDIT_SIGNAL_INFO:
-                err = selinux_sid_to_string(audit_sig_sid, &ctx, &len);
+                err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
                 if (err)
                         return err;
                 sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
                 if (!sig_data) {
-                        kfree(ctx);
+                        security_release_secctx(ctx, len);
                         return -ENOMEM;
                 }
                 sig_data->uid = audit_sig_uid;
                 sig_data->pid = audit_sig_pid;
                 memcpy(sig_data->ctx, ctx, len);
-                kfree(ctx);
+                security_release_secctx(ctx, len);
                 audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_SIGNAL_INFO,
                                 0, 0, sig_data, sizeof(*sig_data) + len);
                 kfree(sig_data);
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 2f2914b7cc30..35e58a146eff 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -28,6 +28,7 @@
 #include <linux/netlink.h>
 #include <linux/sched.h>
 #include <linux/inotify.h>
+#include <linux/security.h>
 #include <linux/selinux.h>
 #include "audit.h"
 
@@ -1515,11 +1516,12 @@ static void audit_log_rule_change(uid_t loginuid, u32 sid, char *action,
         if (sid) {
                 char *ctx = NULL;
                 u32 len;
-                if (selinux_sid_to_string(sid, &ctx, &len))
+                if (security_secid_to_secctx(sid, &ctx, &len))
                         audit_log_format(ab, " ssid=%u", sid);
-                else
+                else {
                         audit_log_format(ab, " subj=%s", ctx);
-                kfree(ctx);
+                        security_release_secctx(ctx, len);
+                }
         }
         audit_log_format(ab, " op=%s rule key=", action);
         if (rule->filterkey)
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 782262e4107d..6a83c706b504 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -530,7 +530,7 @@ static int audit_filter_rules(struct task_struct *tsk,
                            logged upon error */
                         if (f->se_rule) {
                                 if (need_sid) {
-                                        selinux_get_task_sid(tsk, &sid);
+                                        security_task_getsecid(tsk, &sid);
                                         need_sid = 0;
                                 }
                                 result = selinux_audit_rule_match(sid, f->type,
@@ -885,11 +885,11 @@ void audit_log_task_context(struct audit_buffer *ab)
         int error;
         u32 sid;
 
-        selinux_get_task_sid(current, &sid);
+        security_task_getsecid(current, &sid);
         if (!sid)
                 return;
 
-        error = selinux_sid_to_string(sid, &ctx, &len);
+        error = security_secid_to_secctx(sid, &ctx, &len);
         if (error) {
                 if (error != -EINVAL)
                         goto error_path;
@@ -897,7 +897,7 @@ void audit_log_task_context(struct audit_buffer *ab)
         }
 
         audit_log_format(ab, " subj=%s", ctx);
-        kfree(ctx);
+        security_release_secctx(ctx, len);
         return;
 
 error_path:
@@ -941,7 +941,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
                                  u32 sid, char *comm)
 {
         struct audit_buffer *ab;
-        char *s = NULL;
+        char *ctx = NULL;
         u32 len;
         int rc = 0;
 
@@ -951,15 +951,16 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 
         audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid,
                          uid, sessionid);
-        if (selinux_sid_to_string(sid, &s, &len)) {
+        if (security_secid_to_secctx(sid, &ctx, &len)) {
                 audit_log_format(ab, " obj=(none)");
                 rc = 1;
-        } else
-                audit_log_format(ab, " obj=%s", s);
+        } else {
+                audit_log_format(ab, " obj=%s", ctx);
+                security_release_secctx(ctx, len);
+        }
         audit_log_format(ab, " ocomm=");
         audit_log_untrustedstring(ab, comm);
         audit_log_end(ab);
-        kfree(s);
 
         return rc;
 }
@@ -1271,14 +1272,15 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
                         if (axi->osid != 0) {
                                 char *ctx = NULL;
                                 u32 len;
-                                if (selinux_sid_to_string(
+                                if (security_secid_to_secctx(
                                                 axi->osid, &ctx, &len)) {
                                         audit_log_format(ab, " osid=%u",
                                                         axi->osid);
                                         call_panic = 1;
-                                } else
+                                } else {
                                         audit_log_format(ab, " obj=%s", ctx);
-                                kfree(ctx);
+                                        security_release_secctx(ctx, len);
+                                }
                         }
                         break; }
 
@@ -1392,13 +1394,14 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
                 if (n->osid != 0) {
                         char *ctx = NULL;
                         u32 len;
-                        if (selinux_sid_to_string(
+                        if (security_secid_to_secctx(
                                 n->osid, &ctx, &len)) {
                                 audit_log_format(ab, " osid=%u", n->osid);
                                 call_panic = 2;
-                        } else
+                        } else {
                                 audit_log_format(ab, " obj=%s", ctx);
-                        kfree(ctx);
+                                security_release_secctx(ctx, len);
+                        }
                 }
 
                 audit_log_end(ab);
@@ -1775,7 +1778,7 @@ static void audit_copy_inode(struct audit_names *name, const struct inode *inode
         name->uid   = inode->i_uid;
         name->gid   = inode->i_gid;
         name->rdev  = inode->i_rdev;
-        selinux_get_inode_sid(inode, &name->osid);
+        security_inode_getsecid(inode, &name->osid);
 }
 
 /**
@@ -2190,8 +2193,7 @@ int __audit_ipc_obj(struct kern_ipc_perm *ipcp)
         ax->uid = ipcp->uid;
         ax->gid = ipcp->gid;
         ax->mode = ipcp->mode;
-        selinux_get_ipc_sid(ipcp, &ax->osid);
-
+        security_ipc_getsecid(ipcp, &ax->osid);
         ax->d.type = AUDIT_IPC;
         ax->d.next = context->aux;
         context->aux = (void *)ax;
@@ -2343,7 +2345,7 @@ void __audit_ptrace(struct task_struct *t)
         context->target_auid = audit_get_loginuid(t);
         context->target_uid = t->uid;
         context->target_sessionid = audit_get_sessionid(t);
-        selinux_get_task_sid(t, &context->target_sid);
+        security_task_getsecid(t, &context->target_sid);
         memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
 }
 
@@ -2371,7 +2373,7 @@ int __audit_signal_info(int sig, struct task_struct *t)
                                 audit_sig_uid = tsk->loginuid;
                         else
                                 audit_sig_uid = tsk->uid;
-                        selinux_get_task_sid(tsk, &audit_sig_sid);
+                        security_task_getsecid(tsk, &audit_sig_sid);
                 }
                 if (!audit_signals || audit_dummy_context())
                         return 0;
@@ -2384,7 +2386,7 @@ int __audit_signal_info(int sig, struct task_struct *t)
                 ctx->target_auid = audit_get_loginuid(t);
                 ctx->target_uid = t->uid;
                 ctx->target_sessionid = audit_get_sessionid(t);
-                selinux_get_task_sid(t, &ctx->target_sid);
+                security_task_getsecid(t, &ctx->target_sid);
                 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
                 return 0;
         }
@@ -2405,7 +2407,7 @@ int __audit_signal_info(int sig, struct task_struct *t)
         axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
         axp->target_uid[axp->pid_count] = t->uid;
         axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
-        selinux_get_task_sid(t, &axp->target_sid[axp->pid_count]);
+        security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
         memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
         axp->pid_count++;
 
@@ -2435,16 +2437,17 @@ void audit_core_dumps(long signr)
         ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
         audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
                         auid, current->uid, current->gid, sessionid);
-        selinux_get_task_sid(current, &sid);
+        security_task_getsecid(current, &sid);
         if (sid) {
                 char *ctx = NULL;
                 u32 len;
 
-                if (selinux_sid_to_string(sid, &ctx, &len))
+                if (security_secid_to_secctx(sid, &ctx, &len))
                         audit_log_format(ab, " ssid=%u", sid);
-                else
+                else {
                         audit_log_format(ab, " subj=%s", ctx);
-                kfree(ctx);
+                        security_release_secctx(ctx, len);
+                }
         }
         audit_log_format(ab, " pid=%d comm=", current->pid);
         audit_log_untrustedstring(ab, current->comm);