lib: fix the use of LZO to decompress initramfs images

This patch fixes 2 issues with the LZO decompressor:

- It doesn't handle the case where a block isn't compressed at all.  In
  this case, calling lzo1x_decompress_safe will fail, so we need to just
  use memcpy() instead (the upstream LZO code does something similar)

- Since commit 54291362d2 ("initramfs: add
  missing decompressor error check") , the decompressor return code is
  checked in the init/initramfs.c The LZO decompressor didn't return the
  expected value, causing the initramfs code to falsely believe a
  decompression error occured

Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Tested-by: bert schulze <spambemyguest@googlemail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Albin Tonnerre 2010-04-23 13:17:58 -04:00 committed by Linus Torvalds
parent 23be7468e8
commit ccdb40048b

View File

@ -97,7 +97,7 @@ STATIC inline int INIT unlzo(u8 *input, int in_len,
u32 src_len, dst_len;
size_t tmp;
u8 *in_buf, *in_buf_save, *out_buf;
int obytes_processed = 0;
int ret = -1;
set_error_fn(error_fn);
@ -174,15 +174,22 @@ STATIC inline int INIT unlzo(u8 *input, int in_len,
/* decompress */
tmp = dst_len;
r = lzo1x_decompress_safe((u8 *) in_buf, src_len,
/* When the input data is not compressed at all,
* lzo1x_decompress_safe will fail, so call memcpy()
* instead */
if (unlikely(dst_len == src_len))
memcpy(out_buf, in_buf, src_len);
else {
r = lzo1x_decompress_safe((u8 *) in_buf, src_len,
out_buf, &tmp);
if (r != LZO_E_OK || dst_len != tmp) {
error("Compressed data violation");
goto exit_2;
if (r != LZO_E_OK || dst_len != tmp) {
error("Compressed data violation");
goto exit_2;
}
}
obytes_processed += dst_len;
if (flush)
flush(out_buf, dst_len);
if (output)
@ -196,6 +203,7 @@ STATIC inline int INIT unlzo(u8 *input, int in_len,
in_buf += src_len;
}
ret = 0;
exit_2:
if (!input)
free(in_buf);
@ -203,7 +211,7 @@ exit_1:
if (!output)
free(out_buf);
exit:
return obytes_processed;
return ret;
}
#define decompress unlzo