Merge tag 'arm-defconfig-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

[linux-2.6-microblaze.git] / security / selinux / ss / services.c

diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index d91e41d..3016331 100644 (file)
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -1552,6 +1552,7 @@ static int security_context_to_sid_core(struct selinux_state *state,
                if (!str)
                        goto out;
        }
+retry:
        rcu_read_lock();
        policy = rcu_dereference(state->policy);
        policydb = &policy->policydb;
@@ -1565,6 +1566,15 @@ static int security_context_to_sid_core(struct selinux_state *state,
        } else if (rc)
                goto out_unlock;
        rc = sidtab_context_to_sid(sidtab, &context, sid);
+       if (rc == -ESTALE) {
+               rcu_read_unlock();
+               if (context.str) {
+                       str = context.str;
+                       context.str = NULL;
+               }
+               context_destroy(&context);
+               goto retry;
+       }
        context_destroy(&context);
 out_unlock:
        rcu_read_unlock();
@@ -1714,7 +1724,7 @@ static int security_compute_sid(struct selinux_state *state,
        struct selinux_policy *policy;
        struct policydb *policydb;
        struct sidtab *sidtab;
-       struct class_datum *cladatum = NULL;
+       struct class_datum *cladatum;
        struct context *scontext, *tcontext, newcontext;
        struct sidtab_entry *sentry, *tentry;
        struct avtab_key avkey;
@@ -1736,6 +1746,8 @@ static int security_compute_sid(struct selinux_state *state,
                goto out;
        }
 
+retry:
+       cladatum = NULL;
        context_init(&newcontext);
 
        rcu_read_lock();
@@ -1880,6 +1892,11 @@ static int security_compute_sid(struct selinux_state *state,
        }
        /* Obtain the sid for the context. */
        rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid);
+       if (rc == -ESTALE) {
+               rcu_read_unlock();
+               context_destroy(&newcontext);
+               goto retry;
+       }
 out_unlock:
        rcu_read_unlock();
        context_destroy(&newcontext);
@@ -2192,6 +2209,7 @@ void selinux_policy_commit(struct selinux_state *state,
                           struct selinux_load_state *load_state)
 {
        struct selinux_policy *oldpolicy, *newpolicy = load_state->policy;
+       unsigned long flags;
        u32 seqno;
 
        oldpolicy = rcu_dereference_protected(state->policy,
@@ -2213,7 +2231,13 @@ void selinux_policy_commit(struct selinux_state *state,
        seqno = newpolicy->latest_granting;
 
        /* Install the new policy. */
-       rcu_assign_pointer(state->policy, newpolicy);
+       if (oldpolicy) {
+               sidtab_freeze_begin(oldpolicy->sidtab, &flags);
+               rcu_assign_pointer(state->policy, newpolicy);
+               sidtab_freeze_end(oldpolicy->sidtab, &flags);
+       } else {
+               rcu_assign_pointer(state->policy, newpolicy);
+       }
 
        /* Load the policycaps from the new policy */
        security_load_policycaps(state, newpolicy);
@@ -2357,13 +2381,15 @@ int security_port_sid(struct selinux_state *state,
        struct policydb *policydb;
        struct sidtab *sidtab;
        struct ocontext *c;
-       int rc = 0;
+       int rc;
 
        if (!selinux_initialized(state)) {
                *out_sid = SECINITSID_PORT;
                return 0;
        }
 
+retry:
+       rc = 0;
        rcu_read_lock();
        policy = rcu_dereference(state->policy);
        policydb = &policy->policydb;
@@ -2382,6 +2408,10 @@ int security_port_sid(struct selinux_state *state,
                if (!c->sid[0]) {
                        rc = sidtab_context_to_sid(sidtab, &c->context[0],
                                                   &c->sid[0]);
+                       if (rc == -ESTALE) {
+                               rcu_read_unlock();
+                               goto retry;
+                       }
                        if (rc)
                                goto out;
                }
@@ -2408,13 +2438,15 @@ int security_ib_pkey_sid(struct selinux_state *state,
        struct policydb *policydb;
        struct sidtab *sidtab;
        struct ocontext *c;
-       int rc = 0;
+       int rc;
 
        if (!selinux_initialized(state)) {
                *out_sid = SECINITSID_UNLABELED;
                return 0;
        }
 
+retry:
+       rc = 0;
        rcu_read_lock();
        policy = rcu_dereference(state->policy);
        policydb = &policy->policydb;
@@ -2435,6 +2467,10 @@ int security_ib_pkey_sid(struct selinux_state *state,
                        rc = sidtab_context_to_sid(sidtab,
                                                   &c->context[0],
                                                   &c->sid[0]);
+                       if (rc == -ESTALE) {
+                               rcu_read_unlock();
+                               goto retry;
+                       }
                        if (rc)
                                goto out;
                }
@@ -2460,13 +2496,15 @@ int security_ib_endport_sid(struct selinux_state *state,
        struct policydb *policydb;
        struct sidtab *sidtab;
        struct ocontext *c;
-       int rc = 0;
+       int rc;
 
        if (!selinux_initialized(state)) {
                *out_sid = SECINITSID_UNLABELED;
                return 0;
        }
 
+retry:
+       rc = 0;
        rcu_read_lock();
        policy = rcu_dereference(state->policy);
        policydb = &policy->policydb;
@@ -2487,6 +2525,10 @@ int security_ib_endport_sid(struct selinux_state *state,
                if (!c->sid[0]) {
                        rc = sidtab_context_to_sid(sidtab, &c->context[0],
                                                   &c->sid[0]);
+                       if (rc == -ESTALE) {
+                               rcu_read_unlock();
+                               goto retry;
+                       }
                        if (rc)
                                goto out;
                }
@@ -2510,7 +2552,7 @@ int security_netif_sid(struct selinux_state *state,
        struct selinux_policy *policy;
        struct policydb *policydb;
        struct sidtab *sidtab;
-       int rc = 0;
+       int rc;
        struct ocontext *c;
 
        if (!selinux_initialized(state)) {
@@ -2518,6 +2560,8 @@ int security_netif_sid(struct selinux_state *state,
                return 0;
        }
 
+retry:
+       rc = 0;
        rcu_read_lock();
        policy = rcu_dereference(state->policy);
        policydb = &policy->policydb;
@@ -2534,10 +2578,18 @@ int security_netif_sid(struct selinux_state *state,
                if (!c->sid[0] || !c->sid[1]) {
                        rc = sidtab_context_to_sid(sidtab, &c->context[0],
                                                   &c->sid[0]);
+                       if (rc == -ESTALE) {
+                               rcu_read_unlock();
+                               goto retry;
+                       }
                        if (rc)
                                goto out;
                        rc = sidtab_context_to_sid(sidtab, &c->context[1],
                                                   &c->sid[1]);
+                       if (rc == -ESTALE) {
+                               rcu_read_unlock();
+                               goto retry;
+                       }
                        if (rc)
                                goto out;
                }
@@ -2587,6 +2639,7 @@ int security_node_sid(struct selinux_state *state,
                return 0;
        }
 
+retry:
        rcu_read_lock();
        policy = rcu_dereference(state->policy);
        policydb = &policy->policydb;
@@ -2635,6 +2688,10 @@ int security_node_sid(struct selinux_state *state,
                        rc = sidtab_context_to_sid(sidtab,
                                                   &c->context[0],
                                                   &c->sid[0]);
+                       if (rc == -ESTALE) {
+                               rcu_read_unlock();
+                               goto retry;
+                       }
                        if (rc)
                                goto out;
                }
@@ -2676,18 +2733,24 @@ int security_get_user_sids(struct selinux_state *state,
        struct sidtab *sidtab;
        struct context *fromcon, usercon;
        u32 *mysids = NULL, *mysids2, sid;
-       u32 mynel = 0, maxnel = SIDS_NEL;
+       u32 i, j, mynel, maxnel = SIDS_NEL;
        struct user_datum *user;
        struct role_datum *role;
        struct ebitmap_node *rnode, *tnode;
-       int rc = 0, i, j;
+       int rc;
 
        *sids = NULL;
        *nel = 0;
 
        if (!selinux_initialized(state))
-               goto out;
+               return 0;
+
+       mysids = kcalloc(maxnel, sizeof(*mysids), GFP_KERNEL);
+       if (!mysids)
+               return -ENOMEM;
 
+retry:
+       mynel = 0;
        rcu_read_lock();
        policy = rcu_dereference(state->policy);
        policydb = &policy->policydb;
@@ -2707,11 +2770,6 @@ int security_get_user_sids(struct selinux_state *state,
 
        usercon.user = user->value;
 
-       rc = -ENOMEM;
-       mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
-       if (!mysids)
-               goto out_unlock;
-
        ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
                role = policydb->role_val_to_struct[i];
                usercon.role = i + 1;
@@ -2723,6 +2781,10 @@ int security_get_user_sids(struct selinux_state *state,
                                continue;
 
                        rc = sidtab_context_to_sid(sidtab, &usercon, &sid);
+                       if (rc == -ESTALE) {
+                               rcu_read_unlock();
+                               goto retry;
+                       }
                        if (rc)
                                goto out_unlock;
                        if (mynel < maxnel) {
@@ -2745,14 +2807,14 @@ out_unlock:
        rcu_read_unlock();
        if (rc || !mynel) {
                kfree(mysids);
-               goto out;
+               return rc;
        }
 
        rc = -ENOMEM;
        mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
        if (!mysids2) {
                kfree(mysids);
-               goto out;
+               return rc;
        }
        for (i = 0, j = 0; i < mynel; i++) {
                struct av_decision dummy_avd;
@@ -2765,12 +2827,10 @@ out_unlock:
                        mysids2[j++] = mysids[i];
                cond_resched();
        }
-       rc = 0;
        kfree(mysids);
        *sids = mysids2;
        *nel = j;
-out:
-       return rc;
+       return 0;
 }
 
 /**
@@ -2783,6 +2843,9 @@ out:
  * Obtain a SID to use for a file in a filesystem that
  * cannot support xattr or use a fixed labeling behavior like
  * transition SIDs or task SIDs.
+ *
+ * WARNING: This function may return -ESTALE, indicating that the caller
+ * must retry the operation after re-acquiring the policy pointer!
  */
 static inline int __security_genfs_sid(struct selinux_policy *policy,
                                       const char *fstype,
@@ -2861,11 +2924,13 @@ int security_genfs_sid(struct selinux_state *state,
                return 0;
        }
 
-       rcu_read_lock();
-       policy = rcu_dereference(state->policy);
-       retval = __security_genfs_sid(policy,
-                               fstype, path, orig_sclass, sid);
-       rcu_read_unlock();
+       do {
+               rcu_read_lock();
+               policy = rcu_dereference(state->policy);
+               retval = __security_genfs_sid(policy, fstype, path,
+                                             orig_sclass, sid);
+               rcu_read_unlock();
+       } while (retval == -ESTALE);
        return retval;
 }
 
@@ -2888,7 +2953,7 @@ int security_fs_use(struct selinux_state *state, struct super_block *sb)
        struct selinux_policy *policy;
        struct policydb *policydb;
        struct sidtab *sidtab;
-       int rc = 0;
+       int rc;
        struct ocontext *c;
        struct superblock_security_struct *sbsec = sb->s_security;
        const char *fstype = sb->s_type->name;
@@ -2899,6 +2964,8 @@ int security_fs_use(struct selinux_state *state, struct super_block *sb)
                return 0;
        }
 
+retry:
+       rc = 0;
        rcu_read_lock();
        policy = rcu_dereference(state->policy);
        policydb = &policy->policydb;
@@ -2916,6 +2983,10 @@ int security_fs_use(struct selinux_state *state, struct super_block *sb)
                if (!c->sid[0]) {
                        rc = sidtab_context_to_sid(sidtab, &c->context[0],
                                                   &c->sid[0]);
+                       if (rc == -ESTALE) {
+                               rcu_read_unlock();
+                               goto retry;
+                       }
                        if (rc)
                                goto out;
                }
@@ -2923,6 +2994,10 @@ int security_fs_use(struct selinux_state *state, struct super_block *sb)
        } else {
                rc = __security_genfs_sid(policy, fstype, "/",
                                        SECCLASS_DIR, &sbsec->sid);
+               if (rc == -ESTALE) {
+                       rcu_read_unlock();
+                       goto retry;
+               }
                if (rc) {
                        sbsec->behavior = SECURITY_FS_USE_NONE;
                        rc = 0;
@@ -3132,12 +3207,13 @@ int security_sid_mls_copy(struct selinux_state *state,
        u32 len;
        int rc;
 
-       rc = 0;
        if (!selinux_initialized(state)) {
                *new_sid = sid;
-               goto out;
+               return 0;
        }
 
+retry:
+       rc = 0;
        context_init(&newcon);
 
        rcu_read_lock();
@@ -3196,10 +3272,14 @@ int security_sid_mls_copy(struct selinux_state *state,
                }
        }
        rc = sidtab_context_to_sid(sidtab, &newcon, new_sid);
+       if (rc == -ESTALE) {
+               rcu_read_unlock();
+               context_destroy(&newcon);
+               goto retry;
+       }
 out_unlock:
        rcu_read_unlock();
        context_destroy(&newcon);
-out:
        return rc;
 }
 
@@ -3792,6 +3872,8 @@ int security_netlbl_secattr_to_sid(struct selinux_state *state,
                return 0;
        }
 
+retry:
+       rc = 0;
        rcu_read_lock();
        policy = rcu_dereference(state->policy);
        policydb = &policy->policydb;
@@ -3818,23 +3900,24 @@ int security_netlbl_secattr_to_sid(struct selinux_state *state,
                                goto out;
                }
                rc = -EIDRM;
-               if (!mls_context_isvalid(policydb, &ctx_new))
-                       goto out_free;
+               if (!mls_context_isvalid(policydb, &ctx_new)) {
+                       ebitmap_destroy(&ctx_new.range.level[0].cat);
+                       goto out;
+               }
 
                rc = sidtab_context_to_sid(sidtab, &ctx_new, sid);
+               ebitmap_destroy(&ctx_new.range.level[0].cat);
+               if (rc == -ESTALE) {
+                       rcu_read_unlock();
+                       goto retry;
+               }
                if (rc)
-                       goto out_free;
+                       goto out;
 
                security_netlbl_cache_add(secattr, *sid);
-
-               ebitmap_destroy(&ctx_new.range.level[0].cat);
        } else
                *sid = SECSID_NULL;
 
-       rcu_read_unlock();
-       return 0;
-out_free:
-       ebitmap_destroy(&ctx_new.range.level[0].cat);
 out:
        rcu_read_unlock();
        return rc;