tree aaa1f44829044d590d13e1bdf1c3165ed1dbd801
parent 0e81a8ae37687845f7cdfa2adce14ea6a5f1dd34
author Joy Latten <latten@austin.ibm.com> 1207118169 +0800
committer Herbert Xu <herbert@gondor.apana.org.au> 1207118169 +0800

[CRYPTO] xcbc: Fix crash when ipsec uses xcbc-mac with big data chunk

The kernel crashes when ipsec passes a udp packet of about 14XX bytes
of data to aes-xcbc-mac.

It seems the first xxxx bytes of the data are in first sg entry,
and remaining xx bytes are in next sg entry. But we don't 
check next sg entry to see if we need to go look the page up.

I noticed in hmac.c, we do a scatterwalk_sg_next(), to do this check
and possible lookup, thus xcbc.c needs to use this routine too.

A 15-hour run of an ipsec stress test sending streams of tcp and
udp packets of various sizes,  using this patch and 
aes-xcbc-mac completed successfully, so hopefully this fixes the
problem.
 
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>