1 files changed, 147 insertions, 30 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 102a1f0c09..71e6e7079d 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -85,13 +85,15 @@
 #include <linux/export.h>
 #include <linux/msg.h>
 #include <linux/shm.h>
+#include <uapi/linux/shm.h>
 #include <linux/bpf.h>
 #include <linux/kernfs.h>
 #include <linux/stringhash.h>	/* for hashlen_string() */
 #include <uapi/linux/mount.h>
 #include <linux/fsnotify.h>
 #include <linux/fanotify.h>
-#include <linux/io_uring.h>
+#include <linux/io_uring/cmd.h>
+#include <uapi/linux/lsm.h>
 
 #include "avc.h"
 #include "objsec.h"
@@ -2313,6 +2315,19 @@ static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
 	new_tsec->keycreate_sid = 0;
 	new_tsec->sockcreate_sid = 0;
 
+	/*
+	 * Before policy is loaded, label any task outside kernel space
+	 * as SECINITSID_INIT, so that any userspace tasks surviving from
+	 * early boot end up with a label different from SECINITSID_KERNEL
+	 * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL).
+	 */
+	if (!selinux_initialized()) {
+		new_tsec->sid = SECINITSID_INIT;
+		/* also clear the exec_sid just in case */
+		new_tsec->exec_sid = 0;
+		return 0;
+	}
+
 	if (old_tsec->exec_sid) {
 		new_tsec->sid = old_tsec->exec_sid;
 		/* Reset exec SID on execve. */
@@ -4574,6 +4589,21 @@ static int sock_has_perm(struct sock *sk, u32 perms)
 	if (sksec->sid == SECINITSID_KERNEL)
 		return 0;
 
+	/*
+	 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
+	 * inherited the kernel context from early boot used to be skipped
+	 * here, so preserve that behavior unless the capability is set.
+	 *
+	 * By setting the capability the policy signals that it is ready
+	 * for this quirk to be fixed. Note that sockets created by a kernel
+	 * thread or a usermode helper executed without a transition will
+	 * still be skipped in this check regardless of the policycap
+	 * setting.
+	 */
+	if (!selinux_policycap_userspace_initial_context() &&
+	    sksec->sid == SECINITSID_INIT)
+		return 0;
+
 	ad_net_init_from_sk(&ad, &net, sk);
 
 	return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
@@ -6312,8 +6342,8 @@ static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
 		inode_doinit_with_dentry(inode, dentry);
 }
 
-static int selinux_getprocattr(struct task_struct *p,
-			       const char *name, char **value)
+static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
+			       char **value)
 {
 	const struct task_security_struct *__tsec;
 	u32 sid;
@@ -6330,20 +6360,27 @@ static int selinux_getprocattr(struct task_struct *p,
 			goto bad;
 	}
 
-	if (!strcmp(name, "current"))
+	switch (attr) {
+	case LSM_ATTR_CURRENT:
 		sid = __tsec->sid;
-	else if (!strcmp(name, "prev"))
+		break;
+	case LSM_ATTR_PREV:
 		sid = __tsec->osid;
-	else if (!strcmp(name, "exec"))
+		break;
+	case LSM_ATTR_EXEC:
 		sid = __tsec->exec_sid;
-	else if (!strcmp(name, "fscreate"))
+		break;
+	case LSM_ATTR_FSCREATE:
 		sid = __tsec->create_sid;
-	else if (!strcmp(name, "keycreate"))
+		break;
+	case LSM_ATTR_KEYCREATE:
 		sid = __tsec->keycreate_sid;
-	else if (!strcmp(name, "sockcreate"))
+		break;
+	case LSM_ATTR_SOCKCREATE:
 		sid = __tsec->sockcreate_sid;
-	else {
-		error = -EINVAL;
+		break;
+	default:
+		error = -EOPNOTSUPP;
 		goto bad;
 	}
 	rcu_read_unlock();
@@ -6361,7 +6398,7 @@ bad:
 	return error;
 }
 
-static int selinux_setprocattr(const char *name, void *value, size_t size)
+static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
 {
 	struct task_security_struct *tsec;
 	struct cred *new;
@@ -6372,23 +6409,31 @@ static int selinux_setprocattr(const char *name, void *value, size_t size)
 	/*
 	 * Basic control over ability to set these attributes at all.
 	 */
-	if (!strcmp(name, "exec"))
+	switch (attr) {
+	case LSM_ATTR_EXEC:
 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
 				     PROCESS__SETEXEC, NULL);
-	else if (!strcmp(name, "fscreate"))
+		break;
+	case LSM_ATTR_FSCREATE:
 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
 				     PROCESS__SETFSCREATE, NULL);
-	else if (!strcmp(name, "keycreate"))
+		break;
+	case LSM_ATTR_KEYCREATE:
 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
 				     PROCESS__SETKEYCREATE, NULL);
-	else if (!strcmp(name, "sockcreate"))
+		break;
+	case LSM_ATTR_SOCKCREATE:
 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
 				     PROCESS__SETSOCKCREATE, NULL);
-	else if (!strcmp(name, "current"))
+		break;
+	case LSM_ATTR_CURRENT:
 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
 				     PROCESS__SETCURRENT, NULL);
-	else
-		error = -EINVAL;
+		break;
+	default:
+		error = -EOPNOTSUPP;
+		break;
+	}
 	if (error)
 		return error;
 
@@ -6400,13 +6445,14 @@ static int selinux_setprocattr(const char *name, void *value, size_t size)
 		}
 		error = security_context_to_sid(value, size,
 						&sid, GFP_KERNEL);
-		if (error == -EINVAL && !strcmp(name, "fscreate")) {
+		if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
 			if (!has_cap_mac_admin(true)) {
 				struct audit_buffer *ab;
 				size_t audit_size;
 
-				/* We strip a nul only if it is at the end, otherwise the
-				 * context contains a nul and we should audit that */
+				/* We strip a nul only if it is at the end,
+				 * otherwise the context contains a nul and
+				 * we should audit that */
 				if (str[size - 1] == '\0')
 					audit_size = size - 1;
 				else
@@ -6417,7 +6463,8 @@ static int selinux_setprocattr(const char *name, void *value, size_t size)
 				if (!ab)
 					return error;
 				audit_log_format(ab, "op=fscreate invalid_context=");
-				audit_log_n_untrustedstring(ab, value, audit_size);
+				audit_log_n_untrustedstring(ab, value,
+							    audit_size);
 				audit_log_end(ab);
 
 				return error;
@@ -6440,11 +6487,11 @@ static int selinux_setprocattr(const char *name, void *value, size_t size)
 	   checks and may_create for the file creation checks. The
 	   operation will then fail if the context is not permitted. */
 	tsec = selinux_cred(new);
-	if (!strcmp(name, "exec")) {
+	if (attr == LSM_ATTR_EXEC) {
 		tsec->exec_sid = sid;
-	} else if (!strcmp(name, "fscreate")) {
+	} else if (attr == LSM_ATTR_FSCREATE) {
 		tsec->create_sid = sid;
-	} else if (!strcmp(name, "keycreate")) {
+	} else if (attr == LSM_ATTR_KEYCREATE) {
 		if (sid) {
 			error = avc_has_perm(mysid, sid,
 					     SECCLASS_KEY, KEY__CREATE, NULL);
@@ -6452,14 +6499,13 @@ static int selinux_setprocattr(const char *name, void *value, size_t size)
 				goto abort_change;
 		}
 		tsec->keycreate_sid = sid;
-	} else if (!strcmp(name, "sockcreate")) {
+	} else if (attr == LSM_ATTR_SOCKCREATE) {
 		tsec->sockcreate_sid = sid;
-	} else if (!strcmp(name, "current")) {
+	} else if (attr == LSM_ATTR_CURRENT) {
 		error = -EINVAL;
 		if (sid == 0)
 			goto abort_change;
 
-		/* Only allow single threaded processes to change context */
 		if (!current_is_single_threaded()) {
 			error = security_bounded_transition(tsec->sid, sid);
 			if (error)
@@ -6496,6 +6542,69 @@ abort_change:
 	return error;
 }
 
+/**
+ * selinux_getselfattr - Get SELinux current task attributes
+ * @attr: the requested attribute
+ * @ctx: buffer to receive the result
+ * @size: buffer size (input), buffer size used (output)
+ * @flags: unused
+ *
+ * Fill the passed user space @ctx with the details of the requested
+ * attribute.
+ *
+ * Returns the number of attributes on success, an error code otherwise.
+ * There will only ever be one attribute.
+ */
+static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
+			       u32 *size, u32 flags)
+{
+	int rc;
+	char *val = NULL;
+	int val_len;
+
+	val_len = selinux_lsm_getattr(attr, current, &val);
+	if (val_len < 0)
+		return val_len;
+	rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
+	kfree(val);
+	return (!rc ? 1 : rc);
+}
+
+static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
+			       u32 size, u32 flags)
+{
+	int rc;
+
+	rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
+	if (rc > 0)
+		return 0;
+	return rc;
+}
+
+static int selinux_getprocattr(struct task_struct *p,
+			       const char *name, char **value)
+{
+	unsigned int attr = lsm_name_to_attr(name);
+	int rc;
+
+	if (attr) {
+		rc = selinux_lsm_getattr(attr, p, value);
+		if (rc != -EOPNOTSUPP)
+			return rc;
+	}
+
+	return -EINVAL;
+}
+
+static int selinux_setprocattr(const char *name, void *value, size_t size)
+{
+	int attr = lsm_name_to_attr(name);
+
+	if (attr)
+		return selinux_lsm_setattr(attr, value, size);
+	return -EINVAL;
+}
+
 static int selinux_ismaclabel(const char *name)
 {
 	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
@@ -6978,6 +7087,11 @@ static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
 }
 #endif /* CONFIG_IO_URING */
 
+static const struct lsm_id selinux_lsmid = {
+	.name = "selinux",
+	.id = LSM_ID_SELINUX,
+};
+
 /*
  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
  * 1. any hooks that don't belong to (2.) or (3.) below,
@@ -7120,6 +7234,8 @@ static struct security_hook_list selinux_hooks[] __ro_after_init = {
 
 	LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
 
+	LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
+	LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
 	LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
 	LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
 
@@ -7299,7 +7415,8 @@ static __init int selinux_init(void)
 
 	hashtab_cache_init();
 
-	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
+	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
+			   &selinux_lsmid);
 
 	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
 		panic("SELinux: Unable to register AVC netcache callback\n");