nfsd: make nfs4xdr WRITEMEM safe against zero count
authorBenny Halevy <bhalevy@panasas.com>
Thu, 29 May 2008 09:56:08 +0000 (12:56 +0300)
committerJ. Bruce Fields <bfields@citi.umich.edu>
Mon, 23 Jun 2008 17:02:48 +0000 (13:02 -0400)
commit13b1867cacbfe6d8203f432996bd8a2ee6b04e79
tree04c3a0f519f7115073f7b0ca10b5e15669d88515
parent3b12cd9862d5f560031d90bda78952ab55e36b24
nfsd: make nfs4xdr WRITEMEM safe against zero count

WRITEMEM zeroes the last word in the destination buffer
for padding purposes, but this must not be done if
no bytes are to be copied, as it would result
in zeroing of the word right before the array.

The current implementation works since it's always called
with non zero nbytes or it follows an encoding of the
string (or opaque) length which, if equal to zero,
can be overwritten with zero.

Nevertheless, it seems safer to check for this case.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
fs/nfsd/nfs4xdr.c