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bfd_get_full_section_contents memory leak, plus

I noticed that bfd_get_full_section_contents has a memory leak.  If you
set BFD_DECOMPRESS on the BFD, then use bfd_get_full_section_contents to
read a compressed section, the uncompressed section data will be
malloc'd and stored as section->contents -- but nothing ever frees this.

My fix for this (appended) is to allocate the uncompressed data on the
BFD's objalloc.

While looking into this I thought that it would be good to also set
SEC_IN_MEMORY in this case.  I'm less sure of this change.

However, what I'd really like here is a way for gdb to better control
the caching.  Right now, if gdb uses bfd_get_full_section_contents, then
in the compressed case we will have two copies of the section data in
memory -- needlessly wasteful.

Any suggestions for how you would like this to be done?  I could either
add a new function, to be used in lieu of bfd_get_full_section_contents;
or remove the caching entirely; or make a new sentinel initialization
value for the 'ptr' argument to indicate that the function should always
cache the data and never make a copy.

There is a gdb patch series that is blocked on this, so I'd appreciate a
timely answer.


	* compress.c (bfd_get_full_section_contents): Use bfd_alloc
	and bfd_release for allocate uncompressed data.  Set

diff --git a/bfd/compress.c b/bfd/compress.c
index 52c884c..ca71261 100644
--- a/bfd/compress.c
+++ b/bfd/compress.c
@@ -220,7 +220,7 @@ bfd_get_full_section_contents (bfd *abfd, sec_ptr sec, bfd_byte **ptr)
       if (!ret)
 	goto fail_compressed;
-      uncompressed_buffer = (bfd_byte *) bfd_malloc (uncompressed_size);
+      uncompressed_buffer = (bfd_byte *) bfd_alloc (abfd, uncompressed_size);
       if (uncompressed_buffer == NULL)
 	goto fail_compressed;
@@ -228,13 +228,14 @@ bfd_get_full_section_contents (bfd *abfd, sec_ptr sec, bfd_byte **ptr)
 				uncompressed_buffer, uncompressed_size))
 	  bfd_set_error (bfd_error_bad_value);
-	  free (uncompressed_buffer);
+	  bfd_release (abfd, uncompressed_buffer);
 	  free (compressed_buffer);
 	  return FALSE;
       free (compressed_buffer);
+      sec->flags |= SEC_IN_MEMORY;
       sec->contents = uncompressed_buffer;
       sec->compress_status = COMPRESS_SECTION_DONE;
       /* Fall thru */

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