9:59 a.m.
Change the security_current_getsecid_subj() and
security_task_getsecid_obj() interfaces to fill in
a lsmblob structure instead of a u32 secid in support of
LSM stacking. Audit interfaces will need to collect all
possible secids for possible reporting.
Reviewed-by: Kees Cook <keescook(a)chromium.org>
Reviewed-by: John Johansen <john.johansen(a)canonical.com>
Acked-by: Stephen Smalley <stephen.smalley.work(a)gmail.com>
Acked-by: Paul Moore <paul(a)paul-moore.com>
Signed-off-by: Casey Schaufler <casey(a)schaufler-ca.com>
Cc: linux-integrity(a)vger.kernel.org
Cc: linux-audit(a)redhat.com
Cc: netdev(a)vger.kernel.org
---
drivers/android/binder.c | 6 +--
include/linux/security.h | 31 ++++++++++---
kernel/audit.c | 16 +++----
kernel/auditfilter.c | 4 +-
kernel/auditsc.c | 25 +++++------
net/netlabel/netlabel_unlabeled.c | 4 +-
net/netlabel/netlabel_user.h | 6 ++-
security/integrity/ima/ima_appraise.c | 11 ++---
security/integrity/ima/ima_main.c | 63 ++++++++++++++++-----------
security/security.c | 25 ++++++++---
10 files changed, 117 insertions(+), 74 deletions(-)
diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 381a4fddd4a5..bae8440ffc73 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -2980,16 +2980,16 @@ static void binder_transaction(struct binder_proc *proc,
t->priority = task_nice(current);
if (target_node && target_node->txn_security_ctx) {
- u32 secid;
struct lsmblob blob;
size_t added_size;
+ u32 secid;
security_cred_getsecid(proc->cred, &secid);
/*
- * Later in this patch set security_task_getsecid() will
+ * Later in this patch set security_cred_getsecid() will
* provide a lsmblob instead of a secid. lsmblob_init
* is used to ensure that all the secids in the lsmblob
- * get the value returned from security_task_getsecid(),
+ * get the value returned from security_cred_getsecid(),
* which means that the one expected by
* security_secid_to_secctx() will be set.
*/
diff --git a/include/linux/security.h b/include/linux/security.h
index 4cfeb5eb29fc..d11dfa33c1c7 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -220,6 +220,24 @@ static inline u32 lsmblob_value(const struct lsmblob *blob)
return 0;
}
+/**
+ * lsmblob_first - secid value for the first LSM slot
+ * @blob: Pointer to the data
+ *
+ * Return the secid value from the first LSM slot.
+ * There may not be any LSM slots.
+ *
+ * Return the value in secid[0] if there are any slots, 0 otherwise.
+ */
+static inline u32 lsmblob_first(const struct lsmblob *blob)
+{
+#if LSMBLOB_ENTRIES > 0
+ return blob->secid[0];
+#else
+ return 0;
+#endif
+}
+
/* These functions are in security/commoncap.c */
extern int cap_capable(const struct cred *cred, struct user_namespace *ns,
int cap, unsigned int opts);
@@ -502,8 +520,8 @@ int security_task_fix_setgid(struct cred *new, const struct cred
*old,
int security_task_setpgid(struct task_struct *p, pid_t pgid);
int security_task_getpgid(struct task_struct *p);
int security_task_getsid(struct task_struct *p);
-void security_current_getsecid_subj(u32 *secid);
-void security_task_getsecid_obj(struct task_struct *p, u32 *secid);
+void security_current_getsecid_subj(struct lsmblob *blob);
+void security_task_getsecid_obj(struct task_struct *p, struct lsmblob *blob);
int security_task_setnice(struct task_struct *p, int nice);
int security_task_setioprio(struct task_struct *p, int ioprio);
int security_task_getioprio(struct task_struct *p);
@@ -1199,14 +1217,15 @@ static inline int security_task_getsid(struct task_struct *p)
return 0;
}
-static inline void security_current_getsecid_subj(u32 *secid)
+static inline void security_current_getsecid_subj(struct lsmblob *blob)
{
- *secid = 0;
+ lsmblob_init(blob, 0);
}
-static inline void security_task_getsecid_obj(struct task_struct *p, u32 *secid)
+static inline void security_task_getsecid_obj(struct task_struct *p,
+ struct lsmblob *blob)
{
- *secid = 0;
+ lsmblob_init(blob, 0);
}
static inline int security_task_setnice(struct task_struct *p, int nice)
diff --git a/kernel/audit.c b/kernel/audit.c
index 2acf95cf9895..2834e55844db 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -2178,19 +2178,12 @@ int audit_log_task_context(struct audit_buffer *ab)
char *ctx = NULL;
unsigned len;
int error;
- u32 sid;
struct lsmblob blob;
- security_current_getsecid_subj(&sid);
- if (!sid)
+ security_current_getsecid_subj(&blob);
+ if (!lsmblob_is_set(&blob))
return 0;
- /*
- * lsmblob_init sets all values in the lsmblob to sid.
- * This is temporary until security_task_getsecid is converted
- * to use a lsmblob, which happens later in this patch set.
- */
- lsmblob_init(&blob, sid);
error = security_secid_to_secctx(&blob, &ctx, &len);
if (error) {
@@ -2399,6 +2392,7 @@ int audit_set_loginuid(kuid_t loginuid)
int audit_signal_info(int sig, struct task_struct *t)
{
kuid_t uid = current_uid(), auid;
+ struct lsmblob blob;
if (auditd_test_task(t) &&
(sig == SIGTERM || sig == SIGHUP ||
@@ -2409,7 +2403,9 @@ int audit_signal_info(int sig, struct task_struct *t)
audit_sig_uid = auid;
else
audit_sig_uid = uid;
- security_current_getsecid_subj(&audit_sig_sid);
+ security_current_getsecid_subj(&blob);
+ /* scaffolding until audit_sig_sid is converted */
+ audit_sig_sid = lsmblob_first(&blob);
}
return audit_signal_info_syscall(t);
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 15cd4fe35e9c..39ded5cb2429 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -1339,7 +1339,6 @@ int audit_filter(int msgtype, unsigned int listtype)
struct audit_field *f = &e->rule.fields[i];
struct lsmblob blob;
pid_t pid;
- u32 sid;
switch (f->type) {
case AUDIT_PID:
@@ -1369,8 +1368,7 @@ int audit_filter(int msgtype, unsigned int listtype)
case AUDIT_SUBJ_SEN:
case AUDIT_SUBJ_CLR:
if (f->lsm_str) {
- security_current_getsecid_subj(&sid);
- lsmblob_init(&blob, sid);
+ security_current_getsecid_subj(&blob);
result = security_audit_rule_match(
&blob, f->type, f->op,
&f->lsm_rules);
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index d125dba69a76..b7bfc934436d 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -467,7 +467,6 @@ static int audit_filter_rules(struct task_struct *tsk,
{
const struct cred *cred;
int i, need_sid = 1;
- u32 sid;
struct lsmblob blob;
unsigned int sessionid;
@@ -676,17 +675,9 @@ static int audit_filter_rules(struct task_struct *tsk,
* here even though it always refs
* @current's creds
*/
- security_current_getsecid_subj(&sid);
+ security_current_getsecid_subj(&blob);
need_sid = 0;
}
- /*
- * lsmblob_init sets all values in the lsmblob
- * to sid. This is temporary until
- * security_task_getsecid() is converted to
- * provide a lsmblob, which happens later in
- * this patch set.
- */
- lsmblob_init(&blob, sid);
result = security_audit_rule_match(&blob,
f->type, f->op,
&f->lsm_rules);
@@ -2764,12 +2755,15 @@ int __audit_sockaddr(int len, void *a)
void __audit_ptrace(struct task_struct *t)
{
struct audit_context *context = audit_context();
+ struct lsmblob blob;
context->target_pid = task_tgid_nr(t);
context->target_auid = audit_get_loginuid(t);
context->target_uid = task_uid(t);
context->target_sessionid = audit_get_sessionid(t);
- security_task_getsecid_obj(t, &context->target_sid);
+ security_task_getsecid_obj(t, &blob);
+ /* scaffolding - until target_sid is converted */
+ context->target_sid = lsmblob_first(&blob);
memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
}
@@ -2785,6 +2779,7 @@ int audit_signal_info_syscall(struct task_struct *t)
struct audit_aux_data_pids *axp;
struct audit_context *ctx = audit_context();
kuid_t t_uid = task_uid(t);
+ struct lsmblob blob;
if (!audit_signals || audit_dummy_context())
return 0;
@@ -2796,7 +2791,9 @@ int audit_signal_info_syscall(struct task_struct *t)
ctx->target_auid = audit_get_loginuid(t);
ctx->target_uid = t_uid;
ctx->target_sessionid = audit_get_sessionid(t);
- security_task_getsecid_obj(t, &ctx->target_sid);
+ security_task_getsecid_obj(t, &blob);
+ /* scaffolding until target_sid is converted */
+ ctx->target_sid = lsmblob_first(&blob);
memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
return 0;
}
@@ -2817,7 +2814,9 @@ int audit_signal_info_syscall(struct task_struct *t)
axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
axp->target_uid[axp->pid_count] = t_uid;
axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
- security_task_getsecid_obj(t, &axp->target_sid[axp->pid_count]);
+ security_task_getsecid_obj(t, &blob);
+ /* scaffolding until target_sid is converted */
+ axp->target_sid[axp->pid_count] = lsmblob_first(&blob);
memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
axp->pid_count++;
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index 0a99663e6edb..bbb3b6a4f0d7 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -1562,11 +1562,13 @@ int __init netlbl_unlabel_defconf(void)
int ret_val;
struct netlbl_dom_map *entry;
struct netlbl_audit audit_info;
+ struct lsmblob blob;
/* Only the kernel is allowed to call this function and the only time
* it is called is at bootup before the audit subsystem is reporting
* messages so don't worry to much about these values. */
- security_current_getsecid_subj(&audit_info.secid);
+ security_current_getsecid_subj(&blob);
+ audit_info.secid = lsmblob_first(&blob);
audit_info.loginuid = GLOBAL_ROOT_UID;
audit_info.sessionid = 0;
diff --git a/net/netlabel/netlabel_user.h b/net/netlabel/netlabel_user.h
index d6c5b31eb4eb..34bb6572f33b 100644
--- a/net/netlabel/netlabel_user.h
+++ b/net/netlabel/netlabel_user.h
@@ -32,7 +32,11 @@
*/
static inline void netlbl_netlink_auditinfo(struct netlbl_audit *audit_info)
{
- security_current_getsecid_subj(&audit_info->secid);
+ struct lsmblob blob;
+
+ security_current_getsecid_subj(&blob);
+ /* scaffolding until secid is converted */
+ audit_info->secid = lsmblob_first(&blob);
audit_info->loginuid = audit_get_loginuid(current);
audit_info->sessionid = audit_get_sessionid(current);
}
diff --git a/security/integrity/ima/ima_appraise.c
b/security/integrity/ima/ima_appraise.c
index 17232bbfb9f9..f9eadbf53cb6 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -71,15 +71,16 @@ bool is_ima_appraise_enabled(void)
int ima_must_appraise(struct user_namespace *mnt_userns, struct inode *inode,
int mask, enum ima_hooks func)
{
- u32 secid;
+ struct lsmblob blob;
if (!ima_appraise)
return 0;
- security_current_getsecid_subj(&secid);
- return ima_match_policy(mnt_userns, inode, current_cred(), secid,
- func, mask, IMA_APPRAISE | IMA_HASH, NULL,
- NULL, NULL, NULL);
+ security_current_getsecid_subj(&blob);
+ return ima_match_policy(mnt_userns, inode, current_cred(),
+ lsmblob_first(&blob), func, mask,
+ IMA_APPRAISE | IMA_HASH, NULL, NULL, NULL,
+ NULL);
}
static int ima_fix_xattr(struct dentry *dentry,
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 3d3f8c5c502b..3d8d9162a5e3 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -405,12 +405,14 @@ static int process_measurement(struct file *file, const struct cred
*cred,
*/
int ima_file_mmap(struct file *file, unsigned long prot)
{
- u32 secid;
+ struct lsmblob blob;
if (file && (prot & PROT_EXEC)) {
- security_current_getsecid_subj(&secid);
- return process_measurement(file, current_cred(), secid, NULL,
- 0, MAY_EXEC, MMAP_CHECK);
+ security_current_getsecid_subj(&blob);
+ /* scaffolding - until process_measurement changes */
+ return process_measurement(file, current_cred(),
+ lsmblob_first(&blob), NULL, 0,
+ MAY_EXEC, MMAP_CHECK);
}
return 0;
@@ -437,9 +439,9 @@ int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot)
char *pathbuf = NULL;
const char *pathname = NULL;
struct inode *inode;
+ struct lsmblob blob;
int result = 0;
int action;
- u32 secid;
int pcr;
/* Is mprotect making an mmap'ed file executable? */
@@ -447,11 +449,12 @@ int ima_file_mprotect(struct vm_area_struct *vma, unsigned long
prot)
!(prot & PROT_EXEC) || (vma->vm_flags & VM_EXEC))
return 0;
- security_current_getsecid_subj(&secid);
+ security_current_getsecid_subj(&blob);
inode = file_inode(vma->vm_file);
action = ima_get_action(file_mnt_user_ns(vma->vm_file), inode,
- current_cred(), secid, MAY_EXEC, MMAP_CHECK,
- &pcr, &template, NULL, NULL);
+ current_cred(), lsmblob_first(&blob),
+ MAY_EXEC, MMAP_CHECK, &pcr, &template, NULL,
+ NULL);
/* Is the mmap'ed file in policy? */
if (!(action & (IMA_MEASURE | IMA_APPRAISE_SUBMASK)))
@@ -487,10 +490,13 @@ int ima_bprm_check(struct linux_binprm *bprm)
{
int ret;
u32 secid;
+ struct lsmblob blob;
- security_current_getsecid_subj(&secid);
- ret = process_measurement(bprm->file, current_cred(), secid, NULL, 0,
- MAY_EXEC, BPRM_CHECK);
+ security_current_getsecid_subj(&blob);
+ /* scaffolding until process_measurement changes */
+ ret = process_measurement(bprm->file, current_cred(),
+ lsmblob_first(&blob), NULL, 0, MAY_EXEC,
+ BPRM_CHECK);
if (ret)
return ret;
@@ -511,10 +517,12 @@ int ima_bprm_check(struct linux_binprm *bprm)
*/
int ima_file_check(struct file *file, int mask)
{
- u32 secid;
+ struct lsmblob blob;
- security_current_getsecid_subj(&secid);
- return process_measurement(file, current_cred(), secid, NULL, 0,
+ security_current_getsecid_subj(&blob);
+ /* scaffolding until process_measurement changes */
+ return process_measurement(file, current_cred(), lsmblob_first(&blob),
+ NULL, 0,
mask & (MAY_READ | MAY_WRITE | MAY_EXEC |
MAY_APPEND), FILE_CHECK);
}
@@ -710,7 +718,7 @@ int ima_read_file(struct file *file, enum kernel_read_file_id
read_id,
bool contents)
{
enum ima_hooks func;
- u32 secid;
+ struct lsmblob blob;
/*
* Do devices using pre-allocated memory run the risk of the
@@ -730,9 +738,10 @@ int ima_read_file(struct file *file, enum kernel_read_file_id
read_id,
/* Read entire file for all partial reads. */
func = read_idmap[read_id] ?: FILE_CHECK;
- security_current_getsecid_subj(&secid);
- return process_measurement(file, current_cred(), secid, NULL,
- 0, MAY_READ, func);
+ security_current_getsecid_subj(&blob);
+ /* scaffolding - until process_measurement changes */
+ return process_measurement(file, current_cred(), lsmblob_first(&blob),
+ NULL, 0, MAY_READ, func);
}
const int read_idmap[READING_MAX_ID] = {
@@ -760,7 +769,7 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size,
enum kernel_read_file_id read_id)
{
enum ima_hooks func;
- u32 secid;
+ struct lsmblob blob;
/* permit signed certs */
if (!file && read_id == READING_X509_CERTIFICATE)
@@ -773,9 +782,10 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size,
}
func = read_idmap[read_id] ?: FILE_CHECK;
- security_current_getsecid_subj(&secid);
- return process_measurement(file, current_cred(), secid, buf, size,
- MAY_READ, func);
+ security_current_getsecid_subj(&blob);
+ /* scaffolding - until process_measurement changes */
+ return process_measurement(file, current_cred(), lsmblob_first(&blob),
+ buf, size, MAY_READ, func);
}
/**
@@ -900,7 +910,7 @@ int process_buffer_measurement(struct user_namespace *mnt_userns,
int digest_hash_len = hash_digest_size[ima_hash_algo];
int violation = 0;
int action = 0;
- u32 secid;
+ struct lsmblob blob;
if (digest && digest_len < digest_hash_len)
return -EINVAL;
@@ -923,10 +933,11 @@ int process_buffer_measurement(struct user_namespace *mnt_userns,
* buffer measurements.
*/
if (func) {
- security_current_getsecid_subj(&secid);
+ security_current_getsecid_subj(&blob);
+ /* scaffolding */
action = ima_get_action(mnt_userns, inode, current_cred(),
- secid, 0, func, &pcr, &template,
- func_data, NULL);
+ lsmblob_first(&blob), 0, func, &pcr,
+ &template, func_data, NULL);
if (!(action & IMA_MEASURE) && !digest)
return -ENOENT;
}
diff --git a/security/security.c b/security/security.c
index 131c851dd681..eae5b7f3a0db 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1922,17 +1922,30 @@ int security_task_getsid(struct task_struct *p)
return call_int_hook(task_getsid, 0, p);
}
-void security_current_getsecid_subj(u32 *secid)
+void security_current_getsecid_subj(struct lsmblob *blob)
{
- *secid = 0;
- call_void_hook(current_getsecid_subj, secid);
+ struct security_hook_list *hp;
+
+ lsmblob_init(blob, 0);
+ hlist_for_each_entry(hp, &security_hook_heads.current_getsecid_subj,
+ list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ hp->hook.current_getsecid_subj(&blob->secid[hp->lsmid->slot]);
+ }
}
EXPORT_SYMBOL(security_current_getsecid_subj);
-void security_task_getsecid_obj(struct task_struct *p, u32 *secid)
+void security_task_getsecid_obj(struct task_struct *p, struct lsmblob *blob)
{
- *secid = 0;
- call_void_hook(task_getsecid_obj, p, secid);
+ struct security_hook_list *hp;
+
+ lsmblob_init(blob, 0);
+ hlist_for_each_entry(hp, &security_hook_heads.task_getsecid_obj, list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ hp->hook.task_getsecid_obj(p, &blob->secid[hp->lsmid->slot]);
+ }
}
EXPORT_SYMBOL(security_task_getsecid_obj);
--
2.35.1