diff options
Diffstat (limited to 'security/selinux/ss/services.c')
| -rw-r--r-- | security/selinux/ss/services.c | 157 |
1 files changed, 120 insertions, 37 deletions
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index d91e41d47777..301633145040 100644 --- 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; |