__libelf_decompress would only cleanup zlib resources via inflateEnd()
in case inflating was successful, but would leak memory if not. Fix this
by calling inflateEnd() unconditionally.
__libelf_decompress did this all the time already, but called
deflateEnd() twice. That is not a (known) issue, but can be cleaned up
by ensuring all error paths use 'return deflate_cleanup' and the success
path calls deflateEnd() only once. Note, the deflate() needs to return
Z_STREAM_END to indicate we are done. Hence change the condition.
Fixes: 272018bba1f2 ("libelf: Add elf_compress and elf_compress_gnu.")
Signed-off-by: Matthias Maennich <maenn...@google.com>
---
libelf/elf_compress.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/libelf/elf_compress.c b/libelf/elf_compress.c
index 244467b5e3ae..b1b896890ff7 100644
--- a/libelf/elf_compress.c
+++ b/libelf/elf_compress.c
@@ -115,7 +115,7 @@ __libelf_compress (Elf_Scn *scn, size_t hsize, int ei_data,
{
free (out_buf);
__libelf_seterrno (ELF_E_COMPRESS_ERROR);
- return NULL;
+ return deflate_cleanup(NULL, NULL);
}
Elf_Data cdata;
@@ -197,13 +197,13 @@ __libelf_compress (Elf_Scn *scn, size_t hsize, int
ei_data,
}
while (flush != Z_FINISH); /* More data blocks. */
- zrc = deflateEnd (&z);
- if (zrc != Z_OK)
+ if (zrc != Z_STREAM_END)
{
__libelf_seterrno (ELF_E_COMPRESS_ERROR);
return deflate_cleanup (NULL, NULL);
}
+ deflateEnd (&z);
*new_size = used;
return out_buf;
}
@@ -251,16 +251,15 @@ __libelf_decompress (void *buf_in, size_t size_in, size_t
size_out)
}
zrc = inflateReset (&z);
}
- if (likely (zrc == Z_OK))
- zrc = inflateEnd (&z);
if (unlikely (zrc != Z_OK) || unlikely (z.avail_out != 0))
{
free (buf_out);
+ buf_out = NULL;
__libelf_seterrno (ELF_E_DECOMPRESS_ERROR);
- return NULL;
}
+ inflateEnd(&z);
return buf_out;
}
--
2.25.1.696.g5e7596f4ac-goog
