[PATCH v2] Support compressed debug sections larger than 4 GiB

[Alan Modra]

On Sat, May 31, 2025 at 09:16:34PM +0900, Rui Ueyama wrote:
> From: Rui Ueyama <rui314@gmail.com>
> 
> z_stream's avail_in and avail_out are defined as "unsigned int", so it
> cannot decode an entire compressed stream in one pass if the stream is
> larger than 4 GiB. The simplest solution to this problem is to use zlib's
> convenient uncompress2() function, which handles the details for us.
> 
> Signed-off-by: Rui Ueyama <rui314@gmail.com>

Thanks, applied.  I'm going to make the following change, which is
really just fussing.

Some 64-bit compilers have a 32-bit long, which could result in an
endless loop if uncompressed_size is larger than 4G.

diff --git a/bfd/compress.c b/bfd/compress.c
index b693204a3ea..4f92455dbd6 100644
--- a/bfd/compress.c
+++ b/bfd/compress.c
@@ -521,8 +521,10 @@ decompress_contents (bool is_zstd, bfd_byte *compressed_buffer,
      buffers concatenated together, so we uncompress in a loop.  */
   do
     {
-      uLongf dst_len = uncompressed_size;
-      uLong src_len = compressed_size;
+      uLongf dst_len = (uncompressed_size > ULONG_MAX ? ULONG_MAX
+			: uncompressed_size);
+      uLong src_len = (compressed_size > ULONG_MAX ? ULONG_MAX
+		       : compressed_size);
       int rc = uncompress2 ((Bytef *) uncompressed_buffer, &dst_len,
 			    (Bytef *) compressed_buffer, &src_len);
       if (rc != Z_OK)


-- 
Alan Modra