NFSv4: Don't use the delegation->inode in nfs_mark_return_delegation()

nfs_mark_return_delegation() is usually called without any locking, and
so it is not safe to dereference delegation->inode. Since the inode is
only used to discover the nfs_client anyway, it makes more sense to
have the callers pass a valid pointer to the nfs_server as a parameter.

Reported-by: Ian Kent <raven@themaw.net>
Cc: stable@kernel.org
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust 2011-07-25 15:37:29 -04:00
parent 73ca1001ed
commit ed1e6211a0

View File

@ -398,12 +398,11 @@ int nfs_inode_return_delegation(struct inode *inode)
return err;
}
static void nfs_mark_return_delegation(struct nfs_delegation *delegation)
static void nfs_mark_return_delegation(struct nfs_server *server,
struct nfs_delegation *delegation)
{
struct nfs_client *clp = NFS_SERVER(delegation->inode)->nfs_client;
set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
set_bit(NFS4CLNT_DELEGRETURN, &server->nfs_client->cl_state);
}
/**
@ -441,7 +440,7 @@ static void nfs_mark_return_all_delegation_types(struct nfs_server *server,
if ((delegation->type == (FMODE_READ|FMODE_WRITE)) && !(flags & FMODE_WRITE))
continue;
if (delegation->type & flags)
nfs_mark_return_delegation(delegation);
nfs_mark_return_delegation(server, delegation);
}
}
@ -508,7 +507,7 @@ static void nfs_mark_return_unreferenced_delegations(struct nfs_server *server)
list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
if (test_and_clear_bit(NFS_DELEGATION_REFERENCED, &delegation->flags))
continue;
nfs_mark_return_delegation(delegation);
nfs_mark_return_delegation(server, delegation);
}
}
@ -539,7 +538,8 @@ void nfs_expire_unreferenced_delegations(struct nfs_client *clp)
int nfs_async_inode_return_delegation(struct inode *inode,
const nfs4_stateid *stateid)
{
struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
struct nfs_server *server = NFS_SERVER(inode);
struct nfs_client *clp = server->nfs_client;
struct nfs_delegation *delegation;
rcu_read_lock();
@ -549,7 +549,7 @@ int nfs_async_inode_return_delegation(struct inode *inode,
rcu_read_unlock();
return -ENOENT;
}
nfs_mark_return_delegation(delegation);
nfs_mark_return_delegation(server, delegation);
rcu_read_unlock();
nfs_delegation_run_state_manager(clp);