@@ -2024,6 +2024,13 @@ struct security_hook_list {
char *lsm;
} __randomize_layout;
+/*
+ * Security blob size or offset data.
+ */
+struct lsm_blob_sizes {
+ int lbs_cred;
+};
+
/*
* Initializing a security_hook_list structure takes
* up a lot of space in a source file. This macro takes
@@ -2053,6 +2060,7 @@ struct lsm_info {
unsigned long flags; /* Optional: flags describing LSM */
int *enabled; /* Optional: controlled by CONFIG_LSM */
int (*init)(void); /* Required. */
+ struct lsm_blob_sizes *blobs; /* Optional: for blob sharing. */
};
extern struct lsm_info __start_lsm_info[], __end_lsm_info[];
@@ -2092,4 +2100,8 @@ static inline void security_delete_hooks(struct security_hook_list *hooks,
#define __lsm_ro_after_init __ro_after_init
#endif /* CONFIG_SECURITY_WRITABLE_HOOKS */
+#ifdef CONFIG_SECURITY
+void __init lsm_early_cred(struct cred *cred);
+#endif
+
#endif /* ! __LINUX_LSM_HOOKS_H */
@@ -25,7 +25,7 @@
static inline struct aa_label *cred_label(const struct cred *cred)
{
- struct aa_label **blob = cred->security;
+ struct aa_label **blob = cred->security + apparmor_blob_sizes.lbs_cred;
AA_BUG(!blob);
return *blob;
@@ -34,7 +34,7 @@ static inline struct aa_label *cred_label(const struct cred *cred)
static inline void set_cred_label(const struct cred *cred,
struct aa_label *label)
{
- struct aa_label **blob = cred->security;
+ struct aa_label **blob = cred->security + apparmor_blob_sizes.lbs_cred;
AA_BUG(!blob);
*blob = label;
@@ -16,6 +16,7 @@
#include <linux/slab.h>
#include <linux/fs.h>
+#include <linux/lsm_hooks.h>
#include "match.h"
@@ -55,6 +56,9 @@ const char *aa_splitn_fqname(const char *fqname, size_t n, const char **ns_name,
size_t *ns_len);
void aa_info_message(const char *str);
+/* Security blob offsets */
+extern struct lsm_blob_sizes apparmor_blob_sizes;
+
/**
* aa_strneq - compare null terminated @str to a non null terminated substring
* @str: a null terminated string
@@ -1150,6 +1150,13 @@ static int apparmor_inet_conn_request(struct sock *sk, struct sk_buff *skb,
}
#endif
+/*
+ * The cred blob is a pointer to, not an instance of, an aa_task_ctx.
+ */
+struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = {
+ .lbs_cred = sizeof(struct aa_task_ctx *),
+};
+
static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
@@ -1484,6 +1491,7 @@ static int __init set_init_ctx(void)
if (!ctx)
return -ENOMEM;
+ lsm_early_cred(cred);
set_cred_label(cred, aa_get_label(ns_unconfined(root_ns)));
task_ctx(current) = ctx;
@@ -1724,5 +1732,6 @@ DEFINE_LSM(apparmor) = {
.name = "apparmor",
.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
.enabled = &apparmor_enabled,
+ .blobs = &apparmor_blob_sizes,
.init = apparmor_init,
};
@@ -41,6 +41,8 @@ struct security_hook_heads security_hook_heads __lsm_ro_after_init;
static ATOMIC_NOTIFIER_HEAD(lsm_notifier_chain);
char *lsm_names;
+static struct lsm_blob_sizes blob_sizes __lsm_ro_after_init;
+
/* Boot-time LSM user choice */
static __initdata const char *chosen_lsm_order;
static __initdata const char *chosen_major_lsm;
@@ -139,6 +141,25 @@ static bool __init lsm_allowed(struct lsm_info *lsm)
return true;
}
+static void __init lsm_set_blob_size(int *need, int *lbs)
+{
+ int offset;
+
+ if (*need > 0) {
+ offset = *lbs;
+ *lbs += *need;
+ *need = offset;
+ }
+}
+
+static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed)
+{
+ if (!needed)
+ return;
+
+ lsm_set_blob_size(&needed->lbs_cred, &blob_sizes.lbs_cred);
+}
+
/* Prepare LSM for initialization. */
static void __init prepare_lsm(struct lsm_info *lsm)
{
@@ -153,6 +174,8 @@ static void __init prepare_lsm(struct lsm_info *lsm)
exclusive = lsm;
init_debug("exclusive chosen: %s\n", lsm->name);
}
+
+ lsm_set_blob_sizes(lsm->blobs);
}
}
@@ -255,6 +278,8 @@ static void __init ordered_lsm_init(void)
for (lsm = ordered_lsms; *lsm; lsm++)
prepare_lsm(*lsm);
+ init_debug("cred blob size = %d\n", blob_sizes.lbs_cred);
+
for (lsm = ordered_lsms; *lsm; lsm++)
initialize_lsm(*lsm);
@@ -382,6 +407,47 @@ int unregister_lsm_notifier(struct notifier_block *nb)
}
EXPORT_SYMBOL(unregister_lsm_notifier);
+/**
+ * lsm_cred_alloc - allocate a composite cred blob
+ * @cred: the cred that needs a blob
+ * @gfp: allocation type
+ *
+ * Allocate the cred blob for all the modules
+ *
+ * Returns 0, or -ENOMEM if memory can't be allocated.
+ */
+static int lsm_cred_alloc(struct cred *cred, gfp_t gfp)
+{
+ if (blob_sizes.lbs_cred == 0) {
+ cred->security = NULL;
+ return 0;
+ }
+
+ cred->security = kzalloc(blob_sizes.lbs_cred, gfp);
+ if (cred->security == NULL)
+ return -ENOMEM;
+ return 0;
+}
+
+/**
+ * lsm_early_cred - during initialization allocate a composite cred blob
+ * @cred: the cred that needs a blob
+ *
+ * Allocate the cred blob for all the modules if it's not already there
+ */
+void __init lsm_early_cred(struct cred *cred)
+{
+ int rc;
+
+ if (cred == NULL)
+ panic("%s: NULL cred.\n", __func__);
+ if (cred->security != NULL)
+ return;
+ rc = lsm_cred_alloc(cred, GFP_KERNEL);
+ if (rc)
+ panic("%s: Early cred alloc failed.\n", __func__);
+}
+
/*
* Hook list operation macros.
*
@@ -1182,17 +1248,36 @@ void security_task_free(struct task_struct *task)
int security_cred_alloc_blank(struct cred *cred, gfp_t gfp)
{
- return call_int_hook(cred_alloc_blank, 0, cred, gfp);
+ int rc = lsm_cred_alloc(cred, gfp);
+
+ if (rc)
+ return rc;
+
+ rc = call_int_hook(cred_alloc_blank, 0, cred, gfp);
+ if (rc)
+ security_cred_free(cred);
+ return rc;
}
void security_cred_free(struct cred *cred)
{
call_void_hook(cred_free, cred);
+
+ kfree(cred->security);
+ cred->security = NULL;
}
int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp)
{
- return call_int_hook(cred_prepare, 0, new, old, gfp);
+ int rc = lsm_cred_alloc(new, gfp);
+
+ if (rc)
+ return rc;
+
+ rc = call_int_hook(cred_prepare, 0, new, old, gfp);
+ if (rc)
+ security_cred_free(new);
+ return rc;
}
void security_transfer_creds(struct cred *new, const struct cred *old)
@@ -209,12 +209,9 @@ static void cred_init_security(void)
struct cred *cred = (struct cred *) current->real_cred;
struct task_security_struct *tsec;
- tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
- if (!tsec)
- panic("SELinux: Failed to initialize initial task.\n");
-
+ lsm_early_cred(cred);
+ tsec = selinux_cred(cred);
tsec->osid = tsec->sid = SECINITSID_KERNEL;
- cred->security = tsec;
}
/*
@@ -3899,47 +3896,16 @@ static int selinux_task_alloc(struct task_struct *task,
sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
}
-/*
- * allocate the SELinux part of blank credentials
- */
-static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
-{
- struct task_security_struct *tsec;
-
- tsec = kzalloc(sizeof(struct task_security_struct), gfp);
- if (!tsec)
- return -ENOMEM;
-
- cred->security = tsec;
- return 0;
-}
-
-/*
- * detach and free the LSM part of a set of credentials
- */
-static void selinux_cred_free(struct cred *cred)
-{
- struct task_security_struct *tsec = selinux_cred(cred);
-
- kfree(tsec);
-}
-
/*
* prepare a new set of credentials for modification
*/
static int selinux_cred_prepare(struct cred *new, const struct cred *old,
gfp_t gfp)
{
- const struct task_security_struct *old_tsec;
- struct task_security_struct *tsec;
-
- old_tsec = selinux_cred(old);
-
- tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
- if (!tsec)
- return -ENOMEM;
+ const struct task_security_struct *old_tsec = selinux_cred(old);
+ struct task_security_struct *tsec = selinux_cred(new);
- new->security = tsec;
+ *tsec = *old_tsec;
return 0;
}
@@ -6889,6 +6855,10 @@ static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
}
#endif
+struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
+ .lbs_cred = sizeof(struct task_security_struct),
+};
+
static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
@@ -6971,8 +6941,6 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(file_open, selinux_file_open),
LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
- LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
- LSM_HOOK_INIT(cred_free, selinux_cred_free),
LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
@@ -7191,6 +7159,7 @@ DEFINE_LSM(selinux) = {
.name = "selinux",
.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
.enabled = &selinux_enabled,
+ .blobs = &selinux_blob_sizes,
.init = selinux_init,
};
@@ -25,6 +25,7 @@
#include <linux/binfmts.h>
#include <linux/in.h>
#include <linux/spinlock.h>
+#include <linux/lsm_hooks.h>
#include <net/net_namespace.h>
#include "flask.h"
#include "avc.h"
@@ -158,9 +159,10 @@ struct bpf_security_struct {
u32 sid; /*SID of bpf obj creater*/
};
+extern struct lsm_blob_sizes selinux_blob_sizes;
static inline struct task_security_struct *selinux_cred(const struct cred *cred)
{
- return cred->security;
+ return cred->security + selinux_blob_sizes.lbs_cred;
}
#endif /* _SELINUX_OBJSEC_H_ */
@@ -336,6 +336,7 @@ extern struct smack_known *smack_syslog_label;
extern struct smack_known *smack_unconfined;
#endif
extern int smack_ptrace_rule;
+extern struct lsm_blob_sizes smack_blob_sizes;
extern struct smack_known smack_known_floor;
extern struct smack_known smack_known_hat;
@@ -358,7 +359,7 @@ extern struct hlist_head smack_known_hash[SMACK_HASH_SLOTS];
static inline struct task_smack *smack_cred(const struct cred *cred)
{
- return cred->security;
+ return cred->security + smack_blob_sizes.lbs_cred;
}
/*
@@ -309,29 +309,20 @@ static struct inode_smack *new_inode_smack(struct smack_known *skp)
}
/**
- * new_task_smack - allocate a task security blob
+ * init_task_smack - initialize a task security blob
+ * @tsp: blob to initialize
* @task: a pointer to the Smack label for the running task
* @forked: a pointer to the Smack label for the forked task
- * @gfp: type of the memory for the allocation
*
- * Returns the new blob or NULL if there's no memory available
*/
-static struct task_smack *new_task_smack(struct smack_known *task,
- struct smack_known *forked, gfp_t gfp)
+static void init_task_smack(struct task_smack *tsp, struct smack_known *task,
+ struct smack_known *forked)
{
- struct task_smack *tsp;
-
- tsp = kzalloc(sizeof(struct task_smack), gfp);
- if (tsp == NULL)
- return NULL;
-
tsp->smk_task = task;
tsp->smk_forked = forked;
INIT_LIST_HEAD(&tsp->smk_rules);
INIT_LIST_HEAD(&tsp->smk_relabel);
mutex_init(&tsp->smk_rules_lock);
-
- return tsp;
}
/**
@@ -1965,14 +1956,7 @@ static int smack_file_open(struct file *file)
*/
static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
{
- struct task_smack *tsp;
-
- tsp = new_task_smack(NULL, NULL, gfp);
- if (tsp == NULL)
- return -ENOMEM;
-
- cred->security = tsp;
-
+ init_task_smack(smack_cred(cred), NULL, NULL);
return 0;
}
@@ -1989,10 +1973,6 @@ static void smack_cred_free(struct cred *cred)
struct list_head *l;
struct list_head *n;
- if (tsp == NULL)
- return;
- cred->security = NULL;
-
smk_destroy_label_list(&tsp->smk_relabel);
list_for_each_safe(l, n, &tsp->smk_rules) {
@@ -2000,7 +1980,6 @@ static void smack_cred_free(struct cred *cred)
list_del(&rp->list);
kfree(rp);
}
- kfree(tsp);
}
/**
@@ -2015,14 +1994,10 @@ static int smack_cred_prepare(struct cred *new, const struct cred *old,
gfp_t gfp)
{
struct task_smack *old_tsp = smack_cred(old);
- struct task_smack *new_tsp;
+ struct task_smack *new_tsp = smack_cred(new);
int rc;
- new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
- if (new_tsp == NULL)
- return -ENOMEM;
-
- new->security = new_tsp;
+ init_task_smack(new_tsp, old_tsp->smk_task, old_tsp->smk_task);
rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
if (rc != 0)
@@ -2030,10 +2005,7 @@ static int smack_cred_prepare(struct cred *new, const struct cred *old,
rc = smk_copy_relabel(&new_tsp->smk_relabel, &old_tsp->smk_relabel,
gfp);
- if (rc != 0)
- return rc;
-
- return 0;
+ return rc;
}
/**
@@ -4659,6 +4631,10 @@ static int smack_dentry_create_files_as(struct dentry *dentry, int mode,
return 0;
}
+struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = {
+ .lbs_cred = sizeof(struct task_smack),
+};
+
static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
@@ -4837,20 +4813,25 @@ static __init void init_smack_known_list(void)
*/
static __init int smack_init(void)
{
- struct cred *cred;
+ struct cred *cred = (struct cred *) current->cred;
struct task_smack *tsp;
smack_inode_cache = KMEM_CACHE(inode_smack, 0);
if (!smack_inode_cache)
return -ENOMEM;
- tsp = new_task_smack(&smack_known_floor, &smack_known_floor,
- GFP_KERNEL);
- if (tsp == NULL) {
- kmem_cache_destroy(smack_inode_cache);
- return -ENOMEM;
- }
+ lsm_early_cred(cred);
+ /*
+ * Set the security state for the initial task.
+ */
+ tsp = smack_cred(cred);
+ init_task_smack(tsp, &smack_known_floor, &smack_known_floor);
+
+ /*
+ * Register with LSM
+ */
+ security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack");
smack_enabled = 1;
pr_info("Smack: Initializing.\n");
@@ -4864,20 +4845,9 @@ static __init int smack_init(void)
pr_info("Smack: IPv6 Netfilter enabled.\n");
#endif
- /*
- * Set the security state for the initial task.
- */
- cred = (struct cred *) current->cred;
- cred->security = tsp;
-
/* initialize the smack_known_list */
init_smack_known_list();
- /*
- * Register with LSM
- */
- security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack");
-
return 0;
}
@@ -4888,5 +4858,6 @@ static __init int smack_init(void)
DEFINE_LSM(smack) = {
.name = "smack",
.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
+ .blobs = &smack_blob_sizes,
.init = smack_init,
};
@@ -1087,6 +1087,7 @@ extern struct tomoyo_domain_info tomoyo_kernel_domain;
extern struct tomoyo_policy_namespace tomoyo_kernel_namespace;
extern unsigned int tomoyo_memory_quota[TOMOYO_MAX_MEMORY_STAT];
extern unsigned int tomoyo_memory_used[TOMOYO_MAX_MEMORY_STAT];
+extern struct lsm_blob_sizes tomoyo_blob_sizes;
/********** Inlined functions. **********/
@@ -1206,7 +1207,7 @@ static inline void tomoyo_put_group(struct tomoyo_group *group)
*/
static inline struct tomoyo_domain_info **tomoyo_cred(const struct cred *cred)
{
- return (struct tomoyo_domain_info **)&cred->security;
+ return cred->security + tomoyo_blob_sizes.lbs_cred;
}
/**
@@ -509,6 +509,10 @@ static int tomoyo_socket_sendmsg(struct socket *sock, struct msghdr *msg,
return tomoyo_socket_sendmsg_permission(sock, msg, size);
}
+struct lsm_blob_sizes tomoyo_blob_sizes __lsm_ro_after_init = {
+ .lbs_cred = sizeof(struct tomoyo_domain_info *),
+};
+
/*
* tomoyo_security_ops is a "struct security_operations" which is used for
* registering TOMOYO.
@@ -562,6 +566,7 @@ static int __init tomoyo_init(void)
/* register ourselves with the security framework */
security_add_hooks(tomoyo_hooks, ARRAY_SIZE(tomoyo_hooks), "tomoyo");
printk(KERN_INFO "TOMOYO Linux initialized\n");
+ lsm_early_cred(cred);
blob = tomoyo_cred(cred);
*blob = &tomoyo_kernel_domain;
tomoyo_mm_init();
@@ -573,5 +578,6 @@ DEFINE_LSM(tomoyo) = {
.name = "tomoyo",
.enabled = &tomoyo_enabled,
.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
+ .blobs = &tomoyo_blob_sizes,
.init = tomoyo_init,
};