libpayload: cbfs: Require input size and output size for cbfs_decompress

Currently, cbfs_decompress() calls ulzma() and ulz4f() for LZMA/LZ4
decompression. These two functions don't accept input/output size as
parameters. We can make cbfs_decompress more robust by calling ulzman()
and ulz4fn() instead. This could prevent us from overflowing destination
buffer.

BUG=none
BRANCH=none
TEST=boot into kernel on Kukui with COMPRESSED_PAYLOAD_LZMA /
     COMPRESSED_PAYLOAD_LZ4.

Change-Id: Ibe617825bd000ed618791d8e3c5f65bbbd5f7e33
Signed-off-by: You-Cheng Syu <youcheng@google.com>
Reviewed-on: https://review.coreboot.org/c/31606
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Daisuke Nojiri <dnojiri@chromium.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/payloads/libpayload/include/cbfs_core.h b/payloads/libpayload/include/cbfs_core.h
index 364f6c474d..a707154648 100644
--- a/payloads/libpayload/include/cbfs_core.h
+++ b/payloads/libpayload/include/cbfs_core.h
@@ -253,8 +253,9 @@ struct cbfs_media {
 void *cbfs_get_file_content(struct cbfs_media *media, const char *name,
 			    int type, size_t *sz);
 
-/* returns decompressed size on success, 0 on failure */
-int cbfs_decompress(int algo, void *src, void *dst, int len);
+/* Returns decompressed size on success, 0 on failure. */
+size_t cbfs_decompress(int algo, const void *src, size_t srcn, void *dst,
+		       size_t dstn);
 
 /* returns a pointer to CBFS master header, or CBFS_HEADER_INVALID_ADDRESS
  *  on failure */