2017-02-05 01:57:53

by Kinglong Mee

Subject: [PATCH 3/3] nfsd/callback: Drop an useless data copy when comparing sessionid

Signed-off-by: Kinglong Mee <[email protected]>
---
fs/nfsd/nfs4callback.c | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index ea74149..0274db6 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -397,13 +397,10 @@ static int decode_cb_sequence4resok(struct xdr_stream *xdr,
struct nfsd4_callback *cb)
{
struct nfsd4_session *session = cb->cb_clp->cl_cb_session;
- struct nfs4_sessionid id;
- int status;
+ int status = -ESERVERFAULT;
__be32 *p;
u32 dummy;

- status = -ESERVERFAULT;
-
/*
* If the server returns different values for sessionID, slotID or
* sequence number, the server is looney tunes.
@@ -411,9 +408,8 @@ static int decode_cb_sequence4resok(struct xdr_stream *xdr,
p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN + 4 + 4 + 4 + 4);
if (unlikely(p == NULL))
goto out_overflow;
- memcpy(id.data, p, NFS4_MAX_SESSIONID_LEN);
- if (memcmp(id.data, session->se_sessionid.data,
- NFS4_MAX_SESSIONID_LEN) != 0) {
+
+ if (memcmp(p, session->se_sessionid.data, NFS4_MAX_SESSIONID_LEN)) {
dprintk("NFS: %s Invalid session id\n", __func__);
goto out;
}
--
2.9.3

2017-02-17 20:25:48

by J. Bruce Fields

Subject: Re: [PATCH 3/3] nfsd/callback: Drop an useless data copy when comparing sessionid

These three look fine, thanks; applying.--b.

On Sun, Feb 05, 2017 at 09:57:48AM +0800, Kinglong Mee wrote:
> Signed-off-by: Kinglong Mee <[email protected]>
> ---
> fs/nfsd/nfs4callback.c | 10 +++-------
> 1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
> index ea74149..0274db6 100644
> --- a/fs/nfsd/nfs4callback.c
> +++ b/fs/nfsd/nfs4callback.c
> @@ -397,13 +397,10 @@ static int decode_cb_sequence4resok(struct xdr_stream *xdr,
> struct nfsd4_callback *cb)
> {
> struct nfsd4_session *session = cb->cb_clp->cl_cb_session;
> - struct nfs4_sessionid id;
> - int status;
> + int status = -ESERVERFAULT;
> __be32 *p;
> u32 dummy;
>
> - status = -ESERVERFAULT;
> -
> /*
> * If the server returns different values for sessionID, slotID or
> * sequence number, the server is looney tunes.
> @@ -411,9 +408,8 @@ static int decode_cb_sequence4resok(struct xdr_stream *xdr,
> p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN + 4 + 4 + 4 + 4);
> if (unlikely(p == NULL))
> goto out_overflow;
> - memcpy(id.data, p, NFS4_MAX_SESSIONID_LEN);
> - if (memcmp(id.data, session->se_sessionid.data,
> - NFS4_MAX_SESSIONID_LEN) != 0) {
> +
> + if (memcmp(p, session->se_sessionid.data, NFS4_MAX_SESSIONID_LEN)) {
> dprintk("NFS: %s Invalid session id\n", __func__);
> goto out;
> }
> --
> 2.9.3