init/initramfs.c: provide more details in error messages

Use distinct error messages when archive decompression failed.

Link: http://lkml.kernel.org/r/20190212075635.7373-1-david.engraf@sysgo.com
Signed-off-by: David Engraf <david.engraf@sysgo.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

init/initramfs.c

@@ -431,7 +431,7 @@ static long __init flush_buffer(void *bufv, unsigned long len)
 			len -= written;
 			state = Reset;
 		} else
-			error("junk in compressed archive");
+			error("junk within compressed archive");
 	}
 	return origLen;
 }
@@ -488,9 +488,9 @@ static char * __init unpack_to_rootfs(char *buf, unsigned long len)
 				message = msg_buf;
 			}
 		} else
-			error("junk in compressed archive");
+			error("invalid magic at start of compressed archive");
 		if (state != Reset)
-			error("junk in compressed archive");
+			error("junk at the end of compressed archive");
 		this_header = saved_offset + my_inptr;
 		buf += my_inptr;
 		len -= my_inptr;