1 files changed, 173 insertions, 72 deletions

diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index dcc2e1c4fd83..b86ac9da6cf3 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -616,6 +616,14 @@ static int context_struct_to_string(struct context *context, char **scontext, u3
         *scontext = NULL;
         *scontext_len = 0;
 
+        if (context->len) {
+                *scontext_len = context->len;
+                *scontext = kstrdup(context->str, GFP_ATOMIC);
+                if (!(*scontext))
+                        return -ENOMEM;
+                return 0;
+        }
+
         /* Compute the size of the context. */
         *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
         *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
@@ -655,17 +663,8 @@ const char *security_get_initial_sid_context(u32 sid)
         return initial_sid_to_string[sid];
 }
 
-/**
- * security_sid_to_context - Obtain a context for a given SID.
- * @sid: security identifier, SID
- * @scontext: security context
- * @scontext_len: length in bytes
- *
- * Write the string representation of the context associated with @sid
- * into a dynamically allocated string of the correct size.  Set @scontext
- * to point to this string and set @scontext_len to the length of the string.
- */
-int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
+static int security_sid_to_context_core(u32 sid, char **scontext,
+                                        u32 *scontext_len, int force)
 {
         struct context *context;
         int rc = 0;
@@ -693,7 +692,10 @@ int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
                 goto out;
         }
         POLICY_RDLOCK;
-        context = sidtab_search(&sidtab, sid);
+        if (force)
+                context = sidtab_search_force(&sidtab, sid);
+        else
+                context = sidtab_search(&sidtab, sid);
         if (!context) {
                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
                         __func__, sid);
@@ -708,36 +710,44 @@ out:
 
 }
 
-static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
-                                        u32 *sid, u32 def_sid, gfp_t gfp_flags)
+/**
+ * security_sid_to_context - Obtain a context for a given SID.
+ * @sid: security identifier, SID
+ * @scontext: security context
+ * @scontext_len: length in bytes
+ *
+ * Write the string representation of the context associated with @sid
+ * into a dynamically allocated string of the correct size.  Set @scontext
+ * to point to this string and set @scontext_len to the length of the string.
+ */
+int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
 {
-        char *scontext2;
-        struct context context;
+        return security_sid_to_context_core(sid, scontext, scontext_len, 0);
+}
+
+int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
+{
+        return security_sid_to_context_core(sid, scontext, scontext_len, 1);
+}
+
+static int string_to_context_struct(struct policydb *pol,
+                                    struct sidtab *sidtabp,
+                                    const char *scontext,
+                                    u32 scontext_len,
+                                    struct context *ctx,
+                                    u32 def_sid,
+                                    gfp_t gfp_flags)
+{
+        char *scontext2 = NULL;
         struct role_datum *role;
         struct type_datum *typdatum;
         struct user_datum *usrdatum;
         char *scontextp, *p, oldc;
         int rc = 0;
 
-        if (!ss_initialized) {
-                int i;
+        context_init(ctx);
 
-                for (i = 1; i < SECINITSID_NUM; i++) {
-                        if (!strcmp(initial_sid_to_string[i], scontext)) {
-                                *sid = i;
-                                goto out;
-                        }
-                }
-                *sid = SECINITSID_KERNEL;
-                goto out;
-        }
-        *sid = SECSID_NULL;
-
-        /* Copy the string so that we can modify the copy as we parse it.
-           The string should already by null terminated, but we append a
-           null suffix to the copy to avoid problems with the existing
-           attr package, which doesn't view the null terminator as part
-           of the attribute value. */
+        /* Copy the string so that we can modify the copy as we parse it. */
         scontext2 = kmalloc(scontext_len+1, gfp_flags);
         if (!scontext2) {
                 rc = -ENOMEM;
@@ -746,11 +756,6 @@ static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
         memcpy(scontext2, scontext, scontext_len);
         scontext2[scontext_len] = 0;
 
-        context_init(&context);
-        *sid = SECSID_NULL;
-
-        POLICY_RDLOCK;
-
         /* Parse the security context. */
 
         rc = -EINVAL;
@@ -762,15 +767,15 @@ static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
                 p++;
 
         if (*p == 0)
-                goto out_unlock;
+                goto out;
 
         *p++ = 0;
 
-        usrdatum = hashtab_search(policydb.p_users.table, scontextp);
+        usrdatum = hashtab_search(pol->p_users.table, scontextp);
         if (!usrdatum)
-                goto out_unlock;
+                goto out;
 
-        context.user = usrdatum->value;
+        ctx->user = usrdatum->value;
 
         /* Extract role. */
         scontextp = p;
@@ -778,14 +783,14 @@ static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
                 p++;
 
         if (*p == 0)
-                goto out_unlock;
+                goto out;
 
         *p++ = 0;
 
-        role = hashtab_search(policydb.p_roles.table, scontextp);
+        role = hashtab_search(pol->p_roles.table, scontextp);
         if (!role)
-                goto out_unlock;
-        context.role = role->value;
+                goto out;
+        ctx->role = role->value;
 
         /* Extract type. */
         scontextp = p;
@@ -794,33 +799,74 @@ static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
         oldc = *p;
         *p++ = 0;
 
-        typdatum = hashtab_search(policydb.p_types.table, scontextp);
+        typdatum = hashtab_search(pol->p_types.table, scontextp);
         if (!typdatum)
-                goto out_unlock;
+                goto out;
 
-        context.type = typdatum->value;
+        ctx->type = typdatum->value;
 
-        rc = mls_context_to_sid(oldc, &p, &context, &sidtab, def_sid);
+        rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
         if (rc)
-                goto out_unlock;
+                goto out;
 
         if ((p - scontext2) < scontext_len) {
                 rc = -EINVAL;
-                goto out_unlock;
+                goto out;
         }
 
         /* Check the validity of the new context. */
-        if (!policydb_context_isvalid(&policydb, &context)) {
+        if (!policydb_context_isvalid(pol, ctx)) {
                 rc = -EINVAL;
-                goto out_unlock;
+                context_destroy(ctx);
+                goto out;
         }
-        /* Obtain the new sid. */
-        rc = sidtab_context_to_sid(&sidtab, &context, sid);
-out_unlock:
-        POLICY_RDUNLOCK;
-        context_destroy(&context);
+        rc = 0;
+out:
         kfree(scontext2);
+        return rc;
+}
+
+static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
+                                        u32 *sid, u32 def_sid, gfp_t gfp_flags,
+                                        int force)
+{
+        struct context context;
+        int rc = 0;
+
+        if (!ss_initialized) {
+                int i;
+
+                for (i = 1; i < SECINITSID_NUM; i++) {
+                        if (!strcmp(initial_sid_to_string[i], scontext)) {
+                                *sid = i;
+                                goto out;
+                        }
+                }
+                *sid = SECINITSID_KERNEL;
+                goto out;
+        }
+        *sid = SECSID_NULL;
+
+        POLICY_RDLOCK;
+        rc = string_to_context_struct(&policydb, &sidtab,
+                                      scontext, scontext_len,
+                                      &context, def_sid, gfp_flags);
+        if (rc == -EINVAL && force) {
+                context.str = kmalloc(scontext_len+1, gfp_flags);
+                if (!context.str) {
+                        rc = -ENOMEM;
+                        goto out;
+                }
+                memcpy(context.str, scontext, scontext_len);
+                context.str[scontext_len] = 0;
+                context.len = scontext_len;
+        } else if (rc)
+                goto out;
+        rc = sidtab_context_to_sid(&sidtab, &context, sid);
+        if (rc)
+                context_destroy(&context);
 out:
+        POLICY_RDUNLOCK;
         return rc;
 }
 
@@ -838,7 +884,7 @@ out:
 int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid)
 {
         return security_context_to_sid_core(scontext, scontext_len,
-                                            sid, SECSID_NULL, GFP_KERNEL);
+                                            sid, SECSID_NULL, GFP_KERNEL, 0);
 }
 
 /**
@@ -855,6 +901,7 @@ int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid)
  * The default SID is passed to the MLS layer to be used to allow
  * kernel labeling of the MLS field if the MLS field is not present
  * (for upgrading to MLS without full relabel).
+ * Implicitly forces adding of the context even if it cannot be mapped yet.
  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
  * memory is available, or 0 on success.
  */
@@ -862,7 +909,14 @@ int security_context_to_sid_default(const char *scontext, u32 scontext_len,
                                     u32 *sid, u32 def_sid, gfp_t gfp_flags)
 {
         return security_context_to_sid_core(scontext, scontext_len,
-                                            sid, def_sid, gfp_flags);
+                                            sid, def_sid, gfp_flags, 1);
+}
+
+int security_context_to_sid_force(const char *scontext, u32 scontext_len,
+                                  u32 *sid)
+{
+        return security_context_to_sid_core(scontext, scontext_len,
+                                            sid, SECSID_NULL, GFP_KERNEL, 1);
 }
 
 static int compute_sid_handle_invalid_context(
@@ -1246,9 +1300,12 @@ static inline int convert_context_handle_invalid_context(struct context *context
                 char *s;
                 u32 len;
 
-                context_struct_to_string(context, &s, &len);
-                printk(KERN_ERR "SELinux:  context %s is invalid\n", s);
-                kfree(s);
+                if (!context_struct_to_string(context, &s, &len)) {
+                        printk(KERN_WARNING
+                       "SELinux:  Context %s would be invalid if enforcing\n",
+                               s);
+                        kfree(s);
+                }
         }
         return rc;
 }
@@ -1280,6 +1337,32 @@ static int convert_context(u32 key,
 
         args = p;
 
+        if (c->str) {
+                struct context ctx;
+                rc = string_to_context_struct(args->newp, NULL, c->str,
+                                              c->len, &ctx, SECSID_NULL,
+                                              GFP_KERNEL);
+                if (!rc) {
+                        printk(KERN_INFO
+                       "SELinux:  Context %s became valid (mapped).\n",
+                               c->str);
+                        /* Replace string with mapped representation. */
+                        kfree(c->str);
+                        memcpy(c, &ctx, sizeof(*c));
+                        goto out;
+                } else if (rc == -EINVAL) {
+                        /* Retain string representation for later mapping. */
+                        rc = 0;
+                        goto out;
+                } else {
+                        /* Other error condition, e.g. ENOMEM. */
+                        printk(KERN_ERR
+                       "SELinux:   Unable to map context %s, rc = %d.\n",
+                               c->str, -rc);
+                        goto out;
+                }
+        }
+
         rc = context_cpy(&oldc, c);
         if (rc)
                 goto out;
@@ -1319,13 +1402,21 @@ static int convert_context(u32 key,
         }
 
         context_destroy(&oldc);
+        rc = 0;
 out:
         return rc;
 bad:
-        context_struct_to_string(&oldc, &s, &len);
+        /* Map old representation to string and save it. */
+        if (context_struct_to_string(&oldc, &s, &len))
+                return -ENOMEM;
         context_destroy(&oldc);
-        printk(KERN_ERR "SELinux:  invalidating context %s\n", s);
-        kfree(s);
+        context_destroy(c);
+        c->str = s;
+        c->len = len;
+        printk(KERN_INFO
+               "SELinux:  Context %s became invalid (unmapped).\n",
+               c->str);
+        rc = 0;
         goto out;
 }
 
@@ -1406,7 +1497,11 @@ int security_load_policy(void *data, size_t len)
                 return -EINVAL;
         }
 
-        sidtab_init(&newsidtab);
+        if (sidtab_init(&newsidtab)) {
+                LOAD_UNLOCK;
+                policydb_destroy(&newpolicydb);
+                return -ENOMEM;
+        }
 
         /* Verify that the kernel defined classes are correct. */
         if (validate_classes(&newpolicydb)) {
@@ -1429,11 +1524,15 @@ int security_load_policy(void *data, size_t len)
                 goto err;
         }
 
-        /* Convert the internal representations of contexts
-           in the new SID table and remove invalid SIDs. */
+        /*
+         * Convert the internal representations of contexts
+         * in the new SID table.
+         */
         args.oldp = &policydb;
         args.newp = &newpolicydb;
-        sidtab_map_remove_on_error(&newsidtab, convert_context, &args);
+        rc = sidtab_map(&newsidtab, convert_context, &args);
+        if (rc)
+                goto err;
 
         /* Save the old policydb and SID table to free later. */
         memcpy(&oldpolicydb, &policydb, sizeof policydb);
@@ -1673,6 +1772,8 @@ int security_get_user_sids(u32 fromsid,
 
         POLICY_RDLOCK;
 
+        context_init(&usercon);
+
         fromcon = sidtab_search(&sidtab, fromsid);
         if (!fromcon) {
                 rc = -EINVAL;