[PATCH 4.14 62/69] NFSv4: Only pass the delegation to setattr if were sending a truncate

From: Greg Kroah-Hartman
Date: Wed Aug 14 2019 - 13:14:49 EST


From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>

commit 991eedb1371dc09b0f9848f59c8898fe63d198c0 upstream.

Even then it isn't really necessary. The reason why we may not want to
pass in a stateid in other cases is that we cannot use the delegation
credential.

Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/nfs/nfs4proc.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2954,7 +2954,6 @@ static int _nfs4_do_setattr(struct inode
};
struct rpc_cred *delegation_cred = NULL;
unsigned long timestamp = jiffies;
- fmode_t fmode;
bool truncate;
int status;

@@ -2962,11 +2961,12 @@ static int _nfs4_do_setattr(struct inode

/* Servers should only apply open mode checks for file size changes */
truncate = (arg->iap->ia_valid & ATTR_SIZE) ? true : false;
- fmode = truncate ? FMODE_WRITE : FMODE_READ;
+ if (!truncate)
+ goto zero_stateid;

- if (nfs4_copy_delegation_stateid(inode, fmode, &arg->stateid, &delegation_cred)) {
+ if (nfs4_copy_delegation_stateid(inode, FMODE_WRITE, &arg->stateid, &delegation_cred)) {
/* Use that stateid */
- } else if (truncate && ctx != NULL) {
+ } else if (ctx != NULL) {
struct nfs_lock_context *l_ctx;
if (!nfs4_valid_open_stateid(ctx->state))
return -EBADF;
@@ -2978,8 +2978,10 @@ static int _nfs4_do_setattr(struct inode
nfs_put_lock_context(l_ctx);
if (status == -EIO)
return -EBADF;
- } else
+ } else {
+zero_stateid:
nfs4_stateid_copy(&arg->stateid, &zero_stateid);
+ }
if (delegation_cred)
msg.rpc_cred = delegation_cred;