X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=fs%2Fnamespace.c;h=fbba8b17330d40d4daff7cf61763853cfd414395;hb=d5dbc0245a7da65b95fc14f99ccfc5f1fad078f0;hp=348562f14e93b712dfe4f2e335eb39d632c63f28;hpb=1ee07ef6b5db7235b133ee257a3adf507697e6b3;p=karo-tx-linux.git

diff --git a/fs/namespace.c b/fs/namespace.c
index 348562f14e93..fbba8b17330d 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1439,6 +1439,8 @@ static int do_umount(struct mount *mnt, int flags)
 		 * Special case for "unmounting" root ...
 		 * we just try to remount it readonly.
 		 */
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
 		down_write(&sb->s_umount);
 		if (!(sb->s_flags & MS_RDONLY))
 			retval = do_remount_sb(sb, MS_RDONLY, NULL, 0);
@@ -2913,6 +2915,9 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root,
 	/* make sure we can reach put_old from new_root */
 	if (!is_path_reachable(old_mnt, old.dentry, &new))
 		goto out4;
+	/* make certain new is below the root */
+	if (!is_path_reachable(new_mnt, new.dentry, &root))
+		goto out4;
 	root_mp->m_count++; /* pin it so it won't go away */
 	lock_mount_hash();
 	detach_mnt(new_mnt, &parent_path);