selinux: declare data arrays const

The arrays for the policy capability names, the initial sid identifiers
and the class and permission names are not changed at runtime.  Declare
them const to avoid accidental modification.

Do not override the classmap and the initial sid list in the build time
script genheaders.

Check flose(3) is successful in genheaders.c, otherwise the written data
might be corrupted or incomplete.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: manual merge due to fuzz, minor style tweaks]
Signed-off-by: Paul Moore <paul@paul-moore.com>

diff --git a/scripts/selinux/genheaders/genheaders.c b/scripts/selinux/genheaders/genheaders.c
index f355b3e0e968c53ecbdec7f6a1e3394442c1e633..15520806889ee898568913b1cbdaa451e10d20da 100644 (file)
--- a/scripts/selinux/genheaders/genheaders.c
+++ b/scripts/selinux/genheaders/genheaders.c
@@ -59,35 +59,27 @@ int main(int argc, char *argv[])
                exit(2);
        }
 
-       for (i = 0; secclass_map[i].name; i++) {
-               struct security_class_mapping *map = &secclass_map[i];
-               map->name = stoupperx(map->name);
-               for (j = 0; map->perms[j]; j++)
-                       map->perms[j] = stoupperx(map->perms[j]);
-       }
-
-       isids_len = sizeof(initial_sid_to_string) / sizeof (char *);
-       for (i = 1; i < isids_len; i++) {
-               const char *s = initial_sid_to_string[i];
-
-               if (s)
-                       initial_sid_to_string[i] = stoupperx(s);
-       }
-
        fprintf(fout, "/* This file is automatically generated.  Do not edit. */\n");
        fprintf(fout, "#ifndef _SELINUX_FLASK_H_\n#define _SELINUX_FLASK_H_\n\n");
 
        for (i = 0; secclass_map[i].name; i++) {
-               struct security_class_mapping *map = &secclass_map[i];
-               fprintf(fout, "#define SECCLASS_%-39s %2d\n", map->name, i+1);
+               char *name = stoupperx(secclass_map[i].name);
+
+               fprintf(fout, "#define SECCLASS_%-39s %2d\n", name, i+1);
+               free(name);
        }
 
        fprintf(fout, "\n");
 
+       isids_len = sizeof(initial_sid_to_string) / sizeof(char *);
        for (i = 1; i < isids_len; i++) {
                const char *s = initial_sid_to_string[i];
-               if (s)
-                       fprintf(fout, "#define SECINITSID_%-39s %2d\n", s, i);
+               if (s) {
+                       char *sidname = stoupperx(s);
+
+                       fprintf(fout, "#define SECINITSID_%-39s %2d\n", sidname, i);
+                       free(sidname);
+               }
        }
        fprintf(fout, "\n#define SECINITSID_NUM %d\n", i-1);
        fprintf(fout, "\nstatic inline bool security_is_socket_class(u16 kern_tclass)\n");
@@ -96,10 +88,14 @@ int main(int argc, char *argv[])
        fprintf(fout, "\tswitch (kern_tclass) {\n");
        for (i = 0; secclass_map[i].name; i++) {
                static char s[] = "SOCKET";
-               struct security_class_mapping *map = &secclass_map[i];
-               int len = strlen(map->name), l = sizeof(s) - 1;
-               if (len >= l && memcmp(map->name + len - l, s, l) == 0)
-                       fprintf(fout, "\tcase SECCLASS_%s:\n", map->name);
+               int len, l;
+               char *name = stoupperx(secclass_map[i].name);
+
+               len = strlen(name);
+               l = sizeof(s) - 1;
+               if (len >= l && memcmp(name + len - l, s, l) == 0)
+                       fprintf(fout, "\tcase SECCLASS_%s:\n", name);
+               free(name);
        }
        fprintf(fout, "\t\tsock = true;\n");
        fprintf(fout, "\t\tbreak;\n");
@@ -110,33 +106,52 @@ int main(int argc, char *argv[])
        fprintf(fout, "}\n");
 
        fprintf(fout, "\n#endif\n");
-       fclose(fout);
+
+       if (fclose(fout) != 0) {
+               fprintf(stderr, "Could not successfully close %s:  %s\n",
+                       argv[1], strerror(errno));
+               exit(4);
+       }
 
        fout = fopen(argv[2], "w");
        if (!fout) {
                fprintf(stderr, "Could not open %s for writing:  %s\n",
                        argv[2], strerror(errno));
-               exit(4);
+               exit(5);
        }
 
        fprintf(fout, "/* This file is automatically generated.  Do not edit. */\n");
        fprintf(fout, "#ifndef _SELINUX_AV_PERMISSIONS_H_\n#define _SELINUX_AV_PERMISSIONS_H_\n\n");
 
        for (i = 0; secclass_map[i].name; i++) {
-               struct security_class_mapping *map = &secclass_map[i];
-               int len = strlen(map->name);
+               const struct security_class_mapping *map = &secclass_map[i];
+               int len;
+               char *name = stoupperx(map->name);
+
+               len = strlen(name);
                for (j = 0; map->perms[j]; j++) {
+                       char *permname;
+
                        if (j >= 32) {
                                fprintf(stderr, "Too many permissions to fit into an access vector at (%s, %s).\n",
                                        map->name, map->perms[j]);
                                exit(5);
                        }
-                       fprintf(fout, "#define %s__%-*s 0x%08xU\n", map->name,
-                               39-len, map->perms[j], 1U<<j);
+                       permname = stoupperx(map->perms[j]);
+                       fprintf(fout, "#define %s__%-*s 0x%08xU\n", name,
+                               39-len, permname, 1U<<j);
+                       free(permname);
                }
+               free(name);
        }
 
        fprintf(fout, "\n#endif\n");
-       fclose(fout);
+
+       if (fclose(fout) != 0) {
+               fprintf(stderr, "Could not successfully close %s:  %s\n",
+                       argv[2], strerror(errno));
+               exit(6);
+       }
+
        exit(0);
 }

diff --git a/scripts/selinux/mdp/mdp.c b/scripts/selinux/mdp/mdp.c
index 105c1c31a316e1ff4d195151382034762f544363..1415604c3d24ebcbe8ad10cbd0df9b89e09e54d9 100644 (file)
--- a/scripts/selinux/mdp/mdp.c
+++ b/scripts/selinux/mdp/mdp.c
@@ -82,7 +82,7 @@ int main(int argc, char *argv[])
 
        /* print out the class permissions */
        for (i = 0; secclass_map[i].name; i++) {
-               struct security_class_mapping *map = &secclass_map[i];
+               const struct security_class_mapping *map = &secclass_map[i];
                fprintf(fout, "class %s\n", map->name);
                fprintf(fout, "{\n");
                for (j = 0; map->perms[j]; j++)
@@ -103,7 +103,7 @@ int main(int argc, char *argv[])
 #define SYSTEMLOW "s0"
 #define SYSTEMHIGH "s1:c0.c1"
                for (i = 0; secclass_map[i].name; i++) {
-                       struct security_class_mapping *map = &secclass_map[i];
+                       const struct security_class_mapping *map = &secclass_map[i];
 
                        fprintf(fout, "mlsconstrain %s {\n", map->name);
                        for (j = 0; map->perms[j]; j++)

diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index 874c1c6fe10b14ac6a286eb5665c5fc6c6295ad2..9a43af0ebd7de7685f557a8d1ebb54153c3f5938 100644 (file)
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -668,7 +668,7 @@ static void avc_audit_pre_callback(struct audit_buffer *ab, void *a)
        struct common_audit_data *ad = a;
        struct selinux_audit_data *sad = ad->selinux_audit_data;
        u32 av = sad->audited;
-       const char **perms;
+       const char *const *perms;
        int i, perm;
 
        audit_log_format(ab, "avc:  %s ", sad->denied ? "denied" : "granted");

diff --git a/security/selinux/include/avc_ss.h b/security/selinux/include/avc_ss.h
index 66a87559b788bb68013c819a94380bd511afbb51..42912c917fd40c53b4278cd5e820ac3e4686add4 100644 (file)
--- a/security/selinux/include/avc_ss.h
+++ b/security/selinux/include/avc_ss.h
@@ -18,7 +18,7 @@ struct security_class_mapping {
        const char *perms[sizeof(u32) * 8 + 1];
 };
 
-extern struct security_class_mapping secclass_map[];
+extern const struct security_class_mapping secclass_map[];
 
 #endif /* _SELINUX_AVC_SS_H_ */
 

diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h
index 35aac62a662e067bd9af8fa75fe68ff79cb18fb4..ff757ae5f25379ee7fb49887abc0524715a7661b 100644 (file)
--- a/security/selinux/include/classmap.h
+++ b/security/selinux/include/classmap.h
@@ -38,7 +38,7 @@
  * Note: The name for any socket class should be suffixed by "socket",
  *      and doesn't contain more than one substr of "socket".
  */
-struct security_class_mapping secclass_map[] = {
+const struct security_class_mapping secclass_map[] = {
        { "security",
          { "compute_av", "compute_create", "compute_member",
            "check_context", "load_policy", "compute_relabel",

diff --git a/security/selinux/include/initial_sid_to_string.h b/security/selinux/include/initial_sid_to_string.h
index 9683f0ddecbcd6f4947f904d8e31988db04350e2..60820517aa438652b70bc307f7fe1eecd7d52fd2 100644 (file)
--- a/security/selinux/include/initial_sid_to_string.h
+++ b/security/selinux/include/initial_sid_to_string.h
@@ -1,5 +1,5 @@
 /* SPDX-License-Identifier: GPL-2.0 */
-static const char *initial_sid_to_string[] = {
+static const char *const initial_sid_to_string[] = {
        NULL,
        "kernel",
        "security",

diff --git a/security/selinux/include/policycap.h b/security/selinux/include/policycap.h
index 2680aa21205ce2c43db315c9fdf26fb4fa9353e2..f35d3458e71deddc1550d443ba56dbd3936e2410 100644 (file)
--- a/security/selinux/include/policycap.h
+++ b/security/selinux/include/policycap.h
@@ -16,6 +16,6 @@ enum {
 };
 #define POLICYDB_CAP_MAX (__POLICYDB_CAP_MAX - 1)
 
-extern const char *selinux_policycap_names[__POLICYDB_CAP_MAX];
+extern const char *const selinux_policycap_names[__POLICYDB_CAP_MAX];
 
 #endif /* _SELINUX_POLICYCAP_H_ */

diff --git a/security/selinux/include/policycap_names.h b/security/selinux/include/policycap_names.h
index 100da7d043dbf9a2409e5344596668b52a1084cc..2a87fc3702b81a59f71e1eabc786ac8f1a305dd3 100644 (file)
--- a/security/selinux/include/policycap_names.h
+++ b/security/selinux/include/policycap_names.h
@@ -5,7 +5,7 @@
 #include "policycap.h"
 
 /* Policy capability names */
-const char *selinux_policycap_names[__POLICYDB_CAP_MAX] = {
+const char *const selinux_policycap_names[__POLICYDB_CAP_MAX] = {
        "network_peer_controls",
        "open_perms",
        "extended_socket_class",

diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c
index ea9fc69568e3e1fda7a9b0d5926afa03cec91c0c..8480ec6c6e75f69699da6ce7951a732561ce172d 100644 (file)
--- a/security/selinux/ss/avtab.c
+++ b/security/selinux/ss/avtab.c
@@ -385,7 +385,7 @@ void avtab_hash_eval(struct avtab *h, char *tag)
               chain2_len_sum);
 }
 
-static uint16_t spec_order[] = {
+static const uint16_t spec_order[] = {
        AVTAB_ALLOWED,
        AVTAB_AUDITDENY,
        AVTAB_AUDITALLOW,

diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c
index 3d50dfb0211b767a936a73f9fb3142da7b49bfa6..adcfb63b3550db98d0151c78fbd99588437125c3 100644 (file)
--- a/security/selinux/ss/policydb.c
+++ b/security/selinux/ss/policydb.c
@@ -61,7 +61,7 @@ struct policydb_compat_info {
 };
 
 /* These need to be updated if SYM_NUM or OCON_NUM changes */
-static struct policydb_compat_info policydb_compat[] = {
+static const struct policydb_compat_info policydb_compat[] = {
        {
                .version        = POLICYDB_VERSION_BASE,
                .sym_num        = SYM_NUM - 3,
@@ -159,18 +159,16 @@ static struct policydb_compat_info policydb_compat[] = {
        },
 };
 
-static struct policydb_compat_info *policydb_lookup_compat(int version)
+static const struct policydb_compat_info *policydb_lookup_compat(int version)
 {
        int i;
-       struct policydb_compat_info *info = NULL;
 
        for (i = 0; i < ARRAY_SIZE(policydb_compat); i++) {
-               if (policydb_compat[i].version == version) {
-                       info = &policydb_compat[i];
-                       break;
-               }
+               if (policydb_compat[i].version == version)
+                       return &policydb_compat[i];
        }
-       return info;
+
+       return NULL;
 }
 
 /*
@@ -314,7 +312,7 @@ static int cat_destroy(void *key, void *datum, void *p)
        return 0;
 }
 
-static int (*destroy_f[SYM_NUM]) (void *key, void *datum, void *datap) = {
+static int (*const destroy_f[SYM_NUM]) (void *key, void *datum, void *datap) = {
        common_destroy,
        cls_destroy,
        role_destroy,
@@ -669,7 +667,7 @@ static int cat_index(void *key, void *datum, void *datap)
        return 0;
 }
 
-static int (*index_f[SYM_NUM]) (void *key, void *datum, void *datap) = {
+static int (*const index_f[SYM_NUM]) (void *key, void *datum, void *datap) = {
        common_index,
        class_index,
        role_index,
@@ -1637,7 +1635,8 @@ bad:
        return rc;
 }
 
-static int (*read_f[SYM_NUM]) (struct policydb *p, struct symtab *s, void *fp) = {
+static int (*const read_f[SYM_NUM]) (struct policydb *p,
+                                    struct symtab *s, void *fp) = {
        common_read,
        class_read,
        role_read,
@@ -2208,7 +2207,7 @@ out:
        return rc;
 }
 
-static int ocontext_read(struct policydb *p, struct policydb_compat_info *info,
+static int ocontext_read(struct policydb *p, const struct policydb_compat_info *info,
                         void *fp)
 {
        int i, j, rc;
@@ -2404,7 +2403,7 @@ int policydb_read(struct policydb *p, void *fp)
        u32 len, nprim, nel, perm;
 
        char *policydb_str;
-       struct policydb_compat_info *info;
+       const struct policydb_compat_info *info;
 
        policydb_init(p);
 
@@ -3238,8 +3237,7 @@ static int user_write(void *vkey, void *datum, void *ptr)
        return 0;
 }
 
-static int (*write_f[SYM_NUM]) (void *key, void *datum,
-                               void *datap) = {
+static int (*const write_f[SYM_NUM]) (void *key, void *datum, void *datap) = {
        common_write,
        class_write,
        role_write,
@@ -3250,7 +3248,7 @@ static int (*write_f[SYM_NUM]) (void *key, void *datum,
        cat_write,
 };
 
-static int ocontext_write(struct policydb *p, struct policydb_compat_info *info,
+static int ocontext_write(struct policydb *p, const struct policydb_compat_info *info,
                          void *fp)
 {
        unsigned int i, j, rc;
@@ -3607,7 +3605,7 @@ int policydb_write(struct policydb *p, void *fp)
        __le32 buf[4];
        u32 config;
        size_t len;
-       struct policydb_compat_info *info;
+       const struct policydb_compat_info *info;
 
        /*
         * refuse to write policy older than compressed avtab

diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index e62e04b1ec6c47537e959f8aed07622bfe7992f6..69b2734311a69e7df415b1fd373aa4e84c430666 100644 (file)
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -99,7 +99,7 @@ static void context_struct_compute_av(struct policydb *policydb,
                                      struct extended_perms *xperms);
 
 static int selinux_set_mapping(struct policydb *pol,
-                              struct security_class_mapping *map,
+                              const struct security_class_mapping *map,
                               struct selinux_map *out_map)
 {
        u16 i, j;
@@ -121,7 +121,7 @@ static int selinux_set_mapping(struct policydb *pol,
        /* Store the raw class and permission values */
        j = 0;
        while (map[j].name) {
-               struct security_class_mapping *p_in = map + (j++);
+               const struct security_class_mapping *p_in = map + (j++);
                struct selinux_mapping *p_out = out_map->mapping + j;
 
                /* An empty class string skips ahead */