befs: ensure fast symlinks are NUL-terminated

Ensure fast symlink targets are NUL-terminated, even if corrupted
on-disk.

Cc: Sergey S. Kostyliov <rathamahata@php4.ru>
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/befs/linuxvfs.c

@@ -378,7 +378,8 @@ static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
 		inode->i_size = 0;
 		inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
 		strncpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
-			BEFS_SYMLINK_LEN);
+			BEFS_SYMLINK_LEN - 1);
+		befs_ino->i_data.symlink[BEFS_SYMLINK_LEN - 1] = '\0';
 	} else {
 		int num_blks;
 
@@ -477,6 +478,8 @@ befs_follow_link(struct dentry *dentry, struct nameidata *nd)
 			kfree(link);
 			befs_error(sb, "Failed to read entire long symlink");
 			link = ERR_PTR(-EIO);
+		} else {
+			link[len - 1] = '\0';
 		}
 	} else {
 		link = befs_ino->i_data.symlink;