[patch 08/36] libcrc32c: keep intermediate crc state in cpu order

Greg KH
2007-12-13T06:40:01Z

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2.6.22-stable review patch. If anyone has any objections, please let us
know.

------------------

From: Herbert Xu <herbert@gondor.apana.org.au>

It's upstream changeset ef19454bd437b2ba14c9cda1de85debd9f383484.

[LIB] crc32c: Keep intermediate crc state in cpu order

crypto/crc32.c:chksum_final() is computing the digest as
*(__le32 *)out = ~cpu_to_le32(mctx->crc);
so the low-level crc32c_le routines should just keep
the crc in cpu order, otherwise it is getting swabbed
one too many times on big-endian machines.

Signed-off-by: Benny Halevy <bhalevy@fs1.bhalevy.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
lib/libcrc32c.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

--- a/lib/libcrc32c.c
+++ b/lib/libcrc32c.c
@@ -33,7 +33,6 @@
#include <linux/crc32c.h>
#include <linux/compiler.h>
#include <linux/module.h>
-#include <asm/byteorder.h>

MODULE_AUTHOR("Clay Haapala <chaapala@cisco.com>");
MODULE_DESCRIPTION("CRC32c (Castagnoli) calculations");
@@ -161,15 +160,13 @@ static const u32 crc32c_table[256] = {
*/

u32 __attribute_pure__
-crc32c_le(u32 seed, unsigned char const *data, size_t length)
+crc32c_le(u32 crc, unsigned char const *data, size_t length)
{
- u32 crc = __cpu_to_le32(seed);
-
while (length--)
crc =
crc32c_table[(crc ^ *data++) & 0xFFL] ^ (crc >> 8);

- return __le32_to_cpu(crc);
+ return crc;
}

#endif /* CRC_LE_BITS == 8 */

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