2.6.23-stable review patch.  If anyone has any objections, please let us know.
------------------
From: NeilBrown <[EMAIL PROTECTED]>

patch ba67a39efde8312e386c6f603054f8945433d91f in mainline.

When RPCSEC/GSS and krb5i is used, requests are padded, typically to a multiple
of 8 bytes.  This can make the request look slightly longer than it
really is.

As of

        f34b95689d2ce001c "The NFSv2/NFSv3 server does not handle zero
                length WRITE request correctly",

the xdr decode routines for NFSv2 and NFSv3 reject requests that aren't
the right length, so krb5i (for example) WRITE requests can get lost.

This patch relaxes the appropriate test and enhances the related comment.

Signed-off-by: Neil Brown <[EMAIL PROTECTED]>
Signed-off-by: J. Bruce Fields <[EMAIL PROTECTED]>
Cc: Peter Staubach <[EMAIL PROTECTED]>
Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]>
Signed-off-by: Greg Kroah-Hartman <[EMAIL PROTECTED]>

---
 fs/nfsd/nfs3xdr.c |    5 ++++-
 fs/nfsd/nfsxdr.c  |    5 ++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

--- a/fs/nfsd/nfs3xdr.c
+++ b/fs/nfsd/nfs3xdr.c
@@ -396,8 +396,11 @@ nfs3svc_decode_writeargs(struct svc_rqst
         * Round the length of the data which was specified up to
         * the next multiple of XDR units and then compare that
         * against the length which was actually received.
+        * Note that when RPCSEC/GSS (for example) is used, the
+        * data buffer can be padded so dlen might be larger
+        * than required.  It must never be smaller.
         */
-       if (dlen != XDR_QUADLEN(len)*4)
+       if (dlen < XDR_QUADLEN(len)*4)
                return 0;
 
        if (args->count > max_blocksize) {
--- a/fs/nfsd/nfsxdr.c
+++ b/fs/nfsd/nfsxdr.c
@@ -313,8 +313,11 @@ nfssvc_decode_writeargs(struct svc_rqst 
         * Round the length of the data which was specified up to
         * the next multiple of XDR units and then compare that
         * against the length which was actually received.
+        * Note that when RPCSEC/GSS (for example) is used, the
+        * data buffer can be padded so dlen might be larger
+        * than required.  It must never be smaller.
         */
-       if (dlen != XDR_QUADLEN(len)*4)
+       if (dlen < XDR_QUADLEN(len)*4)
                return 0;
 
        rqstp->rq_vec[0].iov_base = (void*)p;

-- 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to