1 files changed, 99 insertions, 130 deletions

diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c
index 9548a0984cc4..dedd97d0c163 100644
--- a/security/tomoyo/tomoyo.c
+++ b/security/tomoyo/tomoyo.c
@@ -11,8 +11,6 @@
 
 #include <linux/security.h>
 #include "common.h"
-#include "tomoyo.h"
-#include "realpath.h"
 
 static int tomoyo_cred_alloc_blank(struct cred *new, gfp_t gfp)
 {
@@ -23,21 +21,23 @@ static int tomoyo_cred_alloc_blank(struct cred *new, gfp_t gfp)
 static int tomoyo_cred_prepare(struct cred *new, const struct cred *old,
 			       gfp_t gfp)
 {
-	/*
-	 * Since "struct tomoyo_domain_info *" is a sharable pointer,
-	 * we don't need to duplicate.
-	 */
-	new->security = old->security;
+	struct tomoyo_domain_info *domain = old->security;
+	new->security = domain;
+	if (domain)
+		atomic_inc(&domain->users);
 	return 0;
 }
 
 static void tomoyo_cred_transfer(struct cred *new, const struct cred *old)
 {
-	/*
-	 * Since "struct tomoyo_domain_info *" is a sharable pointer,
-	 * we don't need to duplicate.
-	 */
-	new->security = old->security;
+	tomoyo_cred_prepare(new, old, 0);
+}
+
+static void tomoyo_cred_free(struct cred *cred)
+{
+	struct tomoyo_domain_info *domain = cred->security;
+	if (domain)
+		atomic_dec(&domain->users);
 }
 
 static int tomoyo_bprm_set_creds(struct linux_binprm *bprm)
@@ -61,6 +61,14 @@ static int tomoyo_bprm_set_creds(struct linux_binprm *bprm)
 	if (!tomoyo_policy_loaded)
 		tomoyo_load_policy(bprm->filename);
 	/*
+	 * Release reference to "struct tomoyo_domain_info" stored inside
+	 * "bprm->cred->security". New reference to "struct tomoyo_domain_info"
+	 * stored inside "bprm->cred->security" will be acquired later inside
+	 * tomoyo_find_next_domain().
+	 */
+	atomic_dec(&((struct tomoyo_domain_info *)
+		     bprm->cred->security)->users);
+	/*
 	 * Tell tomoyo_bprm_check_security() is called for the first time of an
 	 * execve operation.
 	 */
@@ -76,156 +84,71 @@ static int tomoyo_bprm_check_security(struct linux_binprm *bprm)
 	 * Execute permission is checked against pathname passed to do_execve()
 	 * using current domain.
 	 */
-	if (!domain)
-		return tomoyo_find_next_domain(bprm);
+	if (!domain) {
+		const int idx = tomoyo_read_lock();
+		const int err = tomoyo_find_next_domain(bprm);
+		tomoyo_read_unlock(idx);
+		return err;
+	}
 	/*
 	 * Read permission is checked against interpreters using next domain.
-	 * '1' is the result of open_to_namei_flags(O_RDONLY).
 	 */
-	return tomoyo_check_open_permission(domain, &bprm->file->f_path, 1);
-}
-
-#ifdef CONFIG_SYSCTL
-
-static int tomoyo_prepend(char **buffer, int *buflen, const char *str)
-{
-	int namelen = strlen(str);
-
-	if (*buflen < namelen)
-		return -ENOMEM;
-	*buflen -= namelen;
-	*buffer -= namelen;
-	memcpy(*buffer, str, namelen);
-	return 0;
-}
-
-/**
- * tomoyo_sysctl_path - return the realpath of a ctl_table.
- * @table: pointer to "struct ctl_table".
- *
- * Returns realpath(3) of the @table on success.
- * Returns NULL on failure.
- *
- * This function uses tomoyo_alloc(), so the caller must call tomoyo_free()
- * if this function didn't return NULL.
- */
-static char *tomoyo_sysctl_path(struct ctl_table *table)
-{
-	int buflen = TOMOYO_MAX_PATHNAME_LEN;
-	char *buf = tomoyo_alloc(buflen);
-	char *end = buf + buflen;
-	int error = -ENOMEM;
-
-	if (!buf)
-		return NULL;
-
-	*--end = '\0';
-	buflen--;
-	while (table) {
-		char num[32];
-		const char *sp = table->procname;
-
-		if (!sp) {
-			memset(num, 0, sizeof(num));
-			snprintf(num, sizeof(num) - 1, "=%d=", table->ctl_name);
-			sp = num;
-		}
-		if (tomoyo_prepend(&end, &buflen, sp) ||
-		    tomoyo_prepend(&end, &buflen, "/"))
-			goto out;
-		table = table->parent;
-	}
-	if (tomoyo_prepend(&end, &buflen, "/proc/sys"))
-		goto out;
-	error = tomoyo_encode(buf, end - buf, end);
- out:
-	if (!error)
-		return buf;
-	tomoyo_free(buf);
-	return NULL;
-}
-
-static int tomoyo_sysctl(struct ctl_table *table, int op)
-{
-	int error;
-	char *name;
-
-	op &= MAY_READ | MAY_WRITE;
-	if (!op)
-		return 0;
-	name = tomoyo_sysctl_path(table);
-	if (!name)
-		return -ENOMEM;
-	error = tomoyo_check_file_perm(tomoyo_domain(), name, op);
-	tomoyo_free(name);
-	return error;
+	return tomoyo_check_open_permission(domain, &bprm->file->f_path, O_RDONLY);
 }
-#endif
 
 static int tomoyo_path_truncate(struct path *path, loff_t length,
 				unsigned int time_attrs)
 {
-	return tomoyo_check_1path_perm(tomoyo_domain(),
-				       TOMOYO_TYPE_TRUNCATE_ACL,
-				       path);
+	return tomoyo_path_perm(TOMOYO_TYPE_TRUNCATE, path);
 }
 
 static int tomoyo_path_unlink(struct path *parent, struct dentry *dentry)
 {
 	struct path path = { parent->mnt, dentry };
-	return tomoyo_check_1path_perm(tomoyo_domain(),
-				       TOMOYO_TYPE_UNLINK_ACL,
-				       &path);
+	return tomoyo_path_perm(TOMOYO_TYPE_UNLINK, &path);
 }
 
 static int tomoyo_path_mkdir(struct path *parent, struct dentry *dentry,
 			     int mode)
 {
 	struct path path = { parent->mnt, dentry };
-	return tomoyo_check_1path_perm(tomoyo_domain(),
-				       TOMOYO_TYPE_MKDIR_ACL,
-				       &path);
+	return tomoyo_path_perm(TOMOYO_TYPE_MKDIR, &path);
 }
 
 static int tomoyo_path_rmdir(struct path *parent, struct dentry *dentry)
 {
 	struct path path = { parent->mnt, dentry };
-	return tomoyo_check_1path_perm(tomoyo_domain(),
-				       TOMOYO_TYPE_RMDIR_ACL,
-				       &path);
+	return tomoyo_path_perm(TOMOYO_TYPE_RMDIR, &path);
 }
 
 static int tomoyo_path_symlink(struct path *parent, struct dentry *dentry,
 			       const char *old_name)
 {
 	struct path path = { parent->mnt, dentry };
-	return tomoyo_check_1path_perm(tomoyo_domain(),
-				       TOMOYO_TYPE_SYMLINK_ACL,
-				       &path);
+	return tomoyo_path_perm(TOMOYO_TYPE_SYMLINK, &path);
 }
 
 static int tomoyo_path_mknod(struct path *parent, struct dentry *dentry,
 			     int mode, unsigned int dev)
 {
 	struct path path = { parent->mnt, dentry };
-	int type = TOMOYO_TYPE_CREATE_ACL;
+	int type = TOMOYO_TYPE_CREATE;
 
 	switch (mode & S_IFMT) {
 	case S_IFCHR:
-		type = TOMOYO_TYPE_MKCHAR_ACL;
+		type = TOMOYO_TYPE_MKCHAR;
 		break;
 	case S_IFBLK:
-		type = TOMOYO_TYPE_MKBLOCK_ACL;
+		type = TOMOYO_TYPE_MKBLOCK;
 		break;
 	case S_IFIFO:
-		type = TOMOYO_TYPE_MKFIFO_ACL;
+		type = TOMOYO_TYPE_MKFIFO;
 		break;
 	case S_IFSOCK:
-		type = TOMOYO_TYPE_MKSOCK_ACL;
+		type = TOMOYO_TYPE_MKSOCK;
 		break;
 	}
-	return tomoyo_check_1path_perm(tomoyo_domain(),
-				       type, &path);
+	return tomoyo_path_perm(type, &path);
 }
 
 static int tomoyo_path_link(struct dentry *old_dentry, struct path *new_dir,
@@ -233,9 +156,7 @@ static int tomoyo_path_link(struct dentry *old_dentry, struct path *new_dir,
 {
 	struct path path1 = { new_dir->mnt, old_dentry };
 	struct path path2 = { new_dir->mnt, new_dentry };
-	return tomoyo_check_2path_perm(tomoyo_domain(),
-				       TOMOYO_TYPE_LINK_ACL,
-				       &path1, &path2);
+	return tomoyo_path2_perm(TOMOYO_TYPE_LINK, &path1, &path2);
 }
 
 static int tomoyo_path_rename(struct path *old_parent,
@@ -245,32 +166,71 @@ static int tomoyo_path_rename(struct path *old_parent,
 {
 	struct path path1 = { old_parent->mnt, old_dentry };
 	struct path path2 = { new_parent->mnt, new_dentry };
-	return tomoyo_check_2path_perm(tomoyo_domain(),
-				       TOMOYO_TYPE_RENAME_ACL,
-				       &path1, &path2);
+	return tomoyo_path2_perm(TOMOYO_TYPE_RENAME, &path1, &path2);
 }
 
 static int tomoyo_file_fcntl(struct file *file, unsigned int cmd,
 			     unsigned long arg)
 {
 	if (cmd == F_SETFL && ((arg ^ file->f_flags) & O_APPEND))
-		return tomoyo_check_rewrite_permission(tomoyo_domain(), file);
+		return tomoyo_check_rewrite_permission(file);
 	return 0;
 }
 
 static int tomoyo_dentry_open(struct file *f, const struct cred *cred)
 {
 	int flags = f->f_flags;
-
-	if ((flags + 1) & O_ACCMODE)
-		flags++;
-	flags |= f->f_flags & (O_APPEND | O_TRUNC);
 	/* Don't check read permission here if called from do_execve(). */
 	if (current->in_execve)
 		return 0;
 	return tomoyo_check_open_permission(tomoyo_domain(), &f->f_path, flags);
 }
 
+static int tomoyo_file_ioctl(struct file *file, unsigned int cmd,
+			     unsigned long arg)
+{
+	return tomoyo_path_perm(TOMOYO_TYPE_IOCTL, &file->f_path);
+}
+
+static int tomoyo_path_chmod(struct dentry *dentry, struct vfsmount *mnt,
+			     mode_t mode)
+{
+	struct path path = { mnt, dentry };
+	return tomoyo_path_perm(TOMOYO_TYPE_CHMOD, &path);
+}
+
+static int tomoyo_path_chown(struct path *path, uid_t uid, gid_t gid)
+{
+	int error = 0;
+	if (uid != (uid_t) -1)
+		error = tomoyo_path_perm(TOMOYO_TYPE_CHOWN, path);
+	if (!error && gid != (gid_t) -1)
+		error = tomoyo_path_perm(TOMOYO_TYPE_CHGRP, path);
+	return error;
+}
+
+static int tomoyo_path_chroot(struct path *path)
+{
+	return tomoyo_path_perm(TOMOYO_TYPE_CHROOT, path);
+}
+
+static int tomoyo_sb_mount(char *dev_name, struct path *path,
+			   char *type, unsigned long flags, void *data)
+{
+	return tomoyo_path_perm(TOMOYO_TYPE_MOUNT, path);
+}
+
+static int tomoyo_sb_umount(struct vfsmount *mnt, int flags)
+{
+	struct path path = { mnt, mnt->mnt_root };
+	return tomoyo_path_perm(TOMOYO_TYPE_UMOUNT, &path);
+}
+
+static int tomoyo_sb_pivotroot(struct path *old_path, struct path *new_path)
+{
+	return tomoyo_path2_perm(TOMOYO_TYPE_PIVOT_ROOT, new_path, old_path);
+}
+
 /*
  * tomoyo_security_ops is a "struct security_operations" which is used for
  * registering TOMOYO.
@@ -280,11 +240,9 @@ static struct security_operations tomoyo_security_ops = {
 	.cred_alloc_blank    = tomoyo_cred_alloc_blank,
 	.cred_prepare        = tomoyo_cred_prepare,
 	.cred_transfer	     = tomoyo_cred_transfer,
+	.cred_free           = tomoyo_cred_free,
 	.bprm_set_creds      = tomoyo_bprm_set_creds,
 	.bprm_check_security = tomoyo_bprm_check_security,
-#ifdef CONFIG_SYSCTL
-	.sysctl              = tomoyo_sysctl,
-#endif
 	.file_fcntl          = tomoyo_file_fcntl,
 	.dentry_open         = tomoyo_dentry_open,
 	.path_truncate       = tomoyo_path_truncate,
@@ -295,8 +253,18 @@ static struct security_operations tomoyo_security_ops = {
 	.path_mknod          = tomoyo_path_mknod,
 	.path_link           = tomoyo_path_link,
 	.path_rename         = tomoyo_path_rename,
+	.file_ioctl          = tomoyo_file_ioctl,
+	.path_chmod          = tomoyo_path_chmod,
+	.path_chown          = tomoyo_path_chown,
+	.path_chroot         = tomoyo_path_chroot,
+	.sb_mount            = tomoyo_sb_mount,
+	.sb_umount           = tomoyo_sb_umount,
+	.sb_pivotroot        = tomoyo_sb_pivotroot,
 };
 
+/* Lock for GC. */
+struct srcu_struct tomoyo_ss;
+
 static int __init tomoyo_init(void)
 {
 	struct cred *cred = (struct cred *) current_cred();
@@ -304,7 +272,8 @@ static int __init tomoyo_init(void)
 	if (!security_module_enable(&tomoyo_security_ops))
 		return 0;
 	/* register ourselves with the security framework */
-	if (register_security(&tomoyo_security_ops))
+	if (register_security(&tomoyo_security_ops) ||
+	    init_srcu_struct(&tomoyo_ss))
 		panic("Failure registering TOMOYO Linux");
 	printk(KERN_INFO "TOMOYO Linux initialized\n");
 	cred->security = &tomoyo_kernel_domain;