From c60c3269ec9d1bfcec2ec4f6fb450e9a59a0818e Mon Sep 17 00:00:00 2001 From: You-Cheng Syu Date: Tue, 26 Feb 2019 21:41:52 +0800 Subject: [PATCH] libpayload: cbfs: Check decompressed size when loading files After loading compressed files in CBFS, we should check the decompressed size is equal to the expected size. This might help us detect file content corruption or compressor/decompressor bugs. BUG=none BRANCH=none TEST=manually (we can still boot into kernel on Kukui, and verify that loading files from CBFS still works by seeing ChromiumOS firmware screen). Change-Id: Ia756cc5477670dd0d1d8aa59d4160ab4233c6795 Signed-off-by: You-Cheng Syu Reviewed-on: https://review.coreboot.org/c/31564 Reviewed-by: Julius Werner Reviewed-by: Daisuke Nojiri Tested-by: build bot (Jenkins) --- payloads/libpayload/libcbfs/cbfs_core.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/payloads/libpayload/libcbfs/cbfs_core.c b/payloads/libpayload/libcbfs/cbfs_core.c index 4ecda30395..39bbdb5260 100644 --- a/payloads/libpayload/libcbfs/cbfs_core.c +++ b/payloads/libpayload/libcbfs/cbfs_core.c @@ -243,12 +243,9 @@ void *cbfs_get_contents(struct cbfs_handle *handle, size_t *size, size_t limit) } if (algo == CBFS_COMPRESS_NONE) { - if (limit != 0 && limit < on_media_size) { - *size = limit; + if (limit != 0 && limit < on_media_size) on_media_size = limit; - } else { - *size = on_media_size; - } + *size = on_media_size; } void *data = m->map(m, handle->media_offset + handle->content_offset, @@ -257,10 +254,15 @@ void *cbfs_get_contents(struct cbfs_handle *handle, size_t *size, size_t limit) return NULL; ret = malloc(*size); - if (ret != NULL && - !cbfs_decompress(algo, data, on_media_size, ret, *size)) { - free(ret); - ret = NULL; + if (ret != NULL) { + size_t final_size = cbfs_decompress(algo, data, on_media_size, + ret, *size); + if (final_size != *size) { + ERROR("Expect %zu bytes but got %zu bytes after " + "decompression.\n", *size, final_size); + free(ret); + ret = NULL; + } } m->unmap(m, data);