[PATCH] image: Avoid erroneous double byte-swap in CRC value

The hash algorithm selection was streamlined in commit 92055e138f28 ("image: Drop if/elseif hash selection in calculate_hash()"). Said commit kept the call to cpu_to_uimage() to convert the CRC to big endian format.
This would have been correct when calling crc32_wd(). However, the ->hash_func_ws member of crc32 points to crc32_wd_buf(), which already converts the CRC to big endian. On a little endian host, doing both conversions results in a little-endian CRC. This is incorrect.
To remedy this, simply drop the call to cpu_to_uimage(), thus only doing the byte-order conversion once.
Fixes: 92055e138f28 ("image: Drop if/elseif hash selection in calculate_hash()") Tested-by: Tom Rini trini@konsulko.com Signed-off-by: Alexandru Gagniuc mr.nuke.me@gmail.com --- common/image-fit.c | 9 --------- 1 file changed, 9 deletions(-)
diff --git a/common/image-fit.c b/common/image-fit.c index 92d9141bcd..f02d437539 100644 --- a/common/image-fit.c +++ b/common/image-fit.c @@ -1193,12 +1193,6 @@ int fit_set_timestamp(void *fit, int noffset, time_t timestamp) return 0; }
-static void crc32_uimage_fixup(void *value) -{ - /* TODO: In C, this type punning is undefined behavior: */ - *((uint32_t *)value) = cpu_to_uimage(*((uint32_t *)value)); -} - /** * calculate_hash - calculate and return hash for provided input data * @data: pointer to the input data @@ -1232,9 +1226,6 @@ int calculate_hash(const void *data, int data_len, const char *name, algo->hash_func_ws(data, data_len, value, algo->chunk_size); *value_len = algo->digest_size;
- if (!strcmp(name, "crc32")) - crc32_uimage_fixup(value); - return 0; }

On Tue, Sep 14, 2021 at 03:53:33PM -0500, Alexandru Gagniuc wrote:
The hash algorithm selection was streamlined in commit 92055e138f28 ("image: Drop if/elseif hash selection in calculate_hash()"). Said commit kept the call to cpu_to_uimage() to convert the CRC to big endian format.
This would have been correct when calling crc32_wd(). However, the ->hash_func_ws member of crc32 points to crc32_wd_buf(), which already converts the CRC to big endian. On a little endian host, doing both conversions results in a little-endian CRC. This is incorrect.
To remedy this, simply drop the call to cpu_to_uimage(), thus only doing the byte-order conversion once.
Fixes: 92055e138f28 ("image: Drop if/elseif hash selection in calculate_hash()") Tested-by: Tom Rini trini@konsulko.com Signed-off-by: Alexandru Gagniuc mr.nuke.me@gmail.com
Applied to u-boot/master, thanks!
participants (2)
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Alexandru Gagniuc
-
Tom Rini