[PATCH 2/2] lockd: Adjust 61 checks for null pointers

From: SF Markus Elfring
Date: Thu Aug 17 2017 - 10:35:43 EST

From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Date: Thu, 17 Aug 2017 16:00:18 +0200
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The script âcheckpatch.plâ pointed information out like the following.

Comparison to NULL could be written â

Thus fix the affected source code places.

Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
---
fs/lockd/clnt4xdr.c | 12 ++++++------
fs/lockd/clntlock.c | 10 +++++-----
fs/lockd/clntproc.c | 12 ++++++------
fs/lockd/clntxdr.c | 12 ++++++------
fs/lockd/host.c | 22 +++++++++++-----------
fs/lockd/mon.c | 16 ++++++++--------
fs/lockd/svc.c | 4 ++--
fs/lockd/svc4proc.c | 6 +++---
fs/lockd/svclock.c | 14 +++++++-------
fs/lockd/svcproc.c | 6 +++---
fs/lockd/svcshare.c | 2 +-
fs/lockd/svcsubs.c | 3 +--
12 files changed, 59 insertions(+), 60 deletions(-)

diff --git a/fs/lockd/clnt4xdr.c b/fs/lockd/clnt4xdr.c
index c349fc0f9b80..ec6473d194fd 100644
--- a/fs/lockd/clnt4xdr.c
+++ b/fs/lockd/clnt4xdr.c
@@ -131,7 +131,7 @@ static int decode_netobj(struct xdr_stream *xdr,
__be32 *p;

p = xdr_inline_decode(xdr, 4);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
goto out_overflow;
length = be32_to_cpup(p++);
if (unlikely(length > XDR_MAX_NETOBJ))
@@ -163,7 +163,7 @@ static int decode_cookie(struct xdr_stream *xdr,
__be32 *p;

p = xdr_inline_decode(xdr, 4);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
goto out_overflow;
length = be32_to_cpup(p++);
/* apparently HPUX can return empty cookies */
@@ -172,7 +172,7 @@ static int decode_cookie(struct xdr_stream *xdr,
if (length > NLM_MAXCOOKIELEN)
goto out_size;
p = xdr_inline_decode(xdr, length);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
goto out_overflow;
cookie->len = length;
memcpy(cookie->data, p, length);
@@ -234,7 +234,7 @@ static int decode_nlm4_stat(struct xdr_stream *xdr, __be32 *stat)
__be32 *p;

p = xdr_inline_decode(xdr, 4);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
goto out_overflow;
if (unlikely(ntohl(*p) > ntohl(nlm4_failed)))
goto out_bad_xdr;
@@ -289,7 +289,7 @@ static int decode_nlm4_holder(struct xdr_stream *xdr, struct nlm_res *result)
locks_init_lock(fl);

p = xdr_inline_decode(xdr, 4 + 4);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
goto out_overflow;
exclusive = be32_to_cpup(p++);
lock->svid = be32_to_cpup(p);
@@ -300,7 +300,7 @@ static int decode_nlm4_holder(struct xdr_stream *xdr, struct nlm_res *result)
goto out;

p = xdr_inline_decode(xdr, 8 + 8);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
goto out_overflow;

fl->fl_flags = FL_POSIX;
diff --git a/fs/lockd/clntlock.c b/fs/lockd/clntlock.c
index 96c1d14c18f1..ef0cff53dc83 100644
--- a/fs/lockd/clntlock.c
+++ b/fs/lockd/clntlock.c
@@ -64,9 +64,9 @@ struct nlm_host *nlmclnt_init(const struct nlmclnt_initdata *nlm_init)
nlm_init->protocol, nlm_version,
nlm_init->hostname, nlm_init->noresvport,
nlm_init->net);
- if (host == NULL)
+ if (!host)
goto out_nohost;
- if (host->h_rpcclnt == NULL && nlm_bind_host(host) == NULL)
+ if (!host->h_rpcclnt && !nlm_bind_host(host))
goto out_nobind;

host->h_nlmclnt_ops = nlm_init->nlmclnt_ops;
@@ -101,7 +101,7 @@ struct nlm_wait *nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *
struct nlm_wait *block;

block = kmalloc(sizeof(*block), GFP_KERNEL);
- if (block != NULL) {
+ if (block) {
block->b_host = host;
block->b_lock = fl;
init_waitqueue_head(&block->b_wait);
@@ -116,7 +116,7 @@ struct nlm_wait *nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *

void nlmclnt_finish_block(struct nlm_wait *block)
{
- if (block == NULL)
+ if (!block)
return;
spin_lock(&nlm_blocked_lock);
list_del(&block->b_list);
@@ -134,7 +134,7 @@ int nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout)
/* A borken server might ask us to block even if we didn't
* request it. Just say no!
*/
- if (block == NULL)
+ if (!block)
return -EAGAIN;

/* Go to sleep waiting for GRANT callback. Some servers seem
diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c
index 066ac313ae5c..d632d1aa6452 100644
--- a/fs/lockd/clntproc.c
+++ b/fs/lockd/clntproc.c
@@ -98,12 +98,12 @@ static struct nlm_lockowner *nlm_find_lockowner(struct nlm_host *host, fl_owner_

spin_lock(&host->h_lock);
res = __nlm_find_lockowner(host, owner);
- if (res == NULL) {
+ if (!res) {
spin_unlock(&host->h_lock);
new = kmalloc(sizeof(*new), GFP_KERNEL);
spin_lock(&host->h_lock);
res = __nlm_find_lockowner(host, owner);
- if (res == NULL && new != NULL) {
+ if (!res && new) {
res = new;
atomic_set(&new->count, 1);
new->owner = owner;
@@ -142,7 +142,7 @@ static void nlmclnt_setlockargs(struct nlm_rqst *req, struct file_lock *fl)

static void nlmclnt_release_lockargs(struct nlm_rqst *req)
{
- WARN_ON_ONCE(req->a_args.lock.fl.fl_ops != NULL);
+ WARN_ON_ONCE(req->a_args.lock.fl.fl_ops);
}

/**
@@ -160,7 +160,7 @@ int nlmclnt_proc(struct nlm_host *host, int cmd, struct file_lock *fl, void *dat
const struct nlmclnt_operations *nlmclnt_ops = host->h_nlmclnt_ops;

call = nlm_alloc_call(host);
- if (call == NULL)
+ if (!call)
return -ENOMEM;

if (nlmclnt_ops && nlmclnt_ops->nlmclnt_alloc_call)
@@ -203,7 +203,7 @@ struct nlm_rqst *nlm_alloc_call(struct nlm_host *host)

for(;;) {
call = kzalloc(sizeof(*call), GFP_KERNEL);
- if (call != NULL) {
+ if (call) {
atomic_set(&call->a_count, 1);
locks_init_lock(&call->a_args.lock.fl);
locks_init_lock(&call->a_res.lock.fl);
@@ -350,7 +350,7 @@ static struct rpc_task *__nlm_async_call(struct nlm_rqst *req, u32 proc, struct

/* If we have no RPC client yet, create one. */
clnt = nlm_bind_host(host);
- if (clnt == NULL)
+ if (!clnt)
goto out_err;
msg->rpc_proc = &clnt->cl_procinfo[proc];
task_setup_data.rpc_client = clnt;
diff --git a/fs/lockd/clntxdr.c b/fs/lockd/clntxdr.c
index 3b4724a6c4ee..e05124b7897c 100644
--- a/fs/lockd/clntxdr.c
+++ b/fs/lockd/clntxdr.c
@@ -128,7 +128,7 @@ static int decode_netobj(struct xdr_stream *xdr,
__be32 *p;

p = xdr_inline_decode(xdr, 4);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
goto out_overflow;
length = be32_to_cpup(p++);
if (unlikely(length > XDR_MAX_NETOBJ))
@@ -160,7 +160,7 @@ static int decode_cookie(struct xdr_stream *xdr,
__be32 *p;

p = xdr_inline_decode(xdr, 4);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
goto out_overflow;
length = be32_to_cpup(p++);
/* apparently HPUX can return empty cookies */
@@ -169,7 +169,7 @@ static int decode_cookie(struct xdr_stream *xdr,
if (length > NLM_MAXCOOKIELEN)
goto out_size;
p = xdr_inline_decode(xdr, length);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
goto out_overflow;
cookie->len = length;
memcpy(cookie->data, p, length);
@@ -229,7 +229,7 @@ static int decode_nlm_stat(struct xdr_stream *xdr,
__be32 *p;

p = xdr_inline_decode(xdr, 4);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
goto out_overflow;
if (unlikely(ntohl(*p) > ntohl(nlm_lck_denied_grace_period)))
goto out_enum;
@@ -283,7 +283,7 @@ static int decode_nlm_holder(struct xdr_stream *xdr, struct nlm_res *result)
locks_init_lock(fl);

p = xdr_inline_decode(xdr, 4 + 4);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
goto out_overflow;
exclusive = be32_to_cpup(p++);
lock->svid = be32_to_cpup(p);
@@ -294,7 +294,7 @@ static int decode_nlm_holder(struct xdr_stream *xdr, struct nlm_res *result)
goto out;

p = xdr_inline_decode(xdr, 4 + 4);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
goto out_overflow;

fl->fl_flags = FL_POSIX;
diff --git a/fs/lockd/host.c b/fs/lockd/host.c
index d716c9993a26..1aea490ba19a 100644
--- a/fs/lockd/host.c
+++ b/fs/lockd/host.c
@@ -112,13 +112,13 @@ static struct nlm_host *nlm_alloc_host(struct nlm_lookup_host_info *ni,
struct nlm_host *host = NULL;
unsigned long now = jiffies;

- if (nsm != NULL)
+ if (nsm)
atomic_inc(&nsm->sm_count);
else {
host = NULL;
nsm = nsm_get_handle(ni->net, ni->sap, ni->salen,
ni->hostname, ni->hostname_len);
- if (unlikely(nsm == NULL)) {
+ if (unlikely(!nsm)) {
dprintk("lockd: %s failed; no nsm handle\n",
__func__);
goto out;
@@ -126,7 +126,7 @@ static struct nlm_host *nlm_alloc_host(struct nlm_lookup_host_info *ni,
}

host = kmalloc(sizeof(*host), GFP_KERNEL);
- if (unlikely(host == NULL)) {
+ if (unlikely(!host)) {
dprintk("lockd: %s failed; no memory\n", __func__);
nsm_release(nsm);
goto out;
@@ -185,7 +185,7 @@ static void nlm_destroy_host_locked(struct nlm_host *host)
nsm_release(host->h_nsmhandle);

clnt = host->h_rpcclnt;
- if (clnt != NULL)
+ if (clnt)
rpc_shutdown_client(clnt);
kfree(host);

@@ -245,7 +245,7 @@ struct nlm_host *nlmclnt_lookup_host(const struct sockaddr *sap,
continue;

/* Same address. Share an NSM handle if we already have one */
- if (nsm == NULL)
+ if (!nsm)
nsm = host->h_nsmhandle;

if (host->h_proto != protocol)
@@ -260,7 +260,7 @@ struct nlm_host *nlmclnt_lookup_host(const struct sockaddr *sap,
}

host = nlm_alloc_host(&ni, nsm);
- if (unlikely(host == NULL))
+ if (unlikely(!host))
goto out;

hlist_add_head(&host->h_hash, chain);
@@ -282,7 +282,7 @@ struct nlm_host *nlmclnt_lookup_host(const struct sockaddr *sap,
*/
void nlmclnt_release_host(struct nlm_host *host)
{
- if (host == NULL)
+ if (!host)
return;

dprintk("lockd: release client host %s\n", host->h_name);
@@ -357,7 +357,7 @@ struct nlm_host *nlmsvc_lookup_host(const struct svc_rqst *rqstp,
continue;

/* Same address. Share an NSM handle if we already have one */
- if (nsm == NULL)
+ if (!nsm)
nsm = host->h_nsmhandle;

if (host->h_proto != ni.protocol)
@@ -378,7 +378,7 @@ struct nlm_host *nlmsvc_lookup_host(const struct svc_rqst *rqstp,
}

host = nlm_alloc_host(&ni, nsm);
- if (unlikely(host == NULL))
+ if (unlikely(!host))
goto out;

memcpy(nlm_srcaddr(host), src_sap, src_len);
@@ -403,7 +403,7 @@ struct nlm_host *nlmsvc_lookup_host(const struct svc_rqst *rqstp,
*/
void nlmsvc_release_host(struct nlm_host *host)
{
- if (host == NULL)
+ if (!host)
return;

dprintk("lockd: release server host %s\n", host->h_name);
@@ -547,7 +547,7 @@ void nlm_host_rebooted(const struct net *net, const struct nlm_reboot *info)
struct nlm_host *host;

nsm = nsm_reboot_lookup(net, info);
- if (unlikely(nsm == NULL))
+ if (unlikely(!nsm))
return;

/* Mark all hosts tied to this NSM state as having rebooted.
diff --git a/fs/lockd/mon.c b/fs/lockd/mon.c
index 9d8166c39c54..3aa95a7ed4a0 100644
--- a/fs/lockd/mon.c
+++ b/fs/lockd/mon.c
@@ -274,7 +274,7 @@ static struct nsm_handle *nsm_create_handle(const struct sockaddr *sap,
struct nsm_handle *new;

new = kzalloc(sizeof(*new) + hostname_len + 1, GFP_KERNEL);
- if (unlikely(new == NULL))
+ if (unlikely(!new))
return NULL;

atomic_set(&new->sm_count, 1);
@@ -328,13 +328,13 @@ struct nsm_handle *nsm_get_handle(const struct net *net,
retry:
spin_lock(&nsm_lock);

- if (nsm_use_hostnames && hostname != NULL)
+ if (nsm_use_hostnames && hostname)
cached = nsm_lookup_hostname(&ln->nsm_handles,
hostname, hostname_len);
else
cached = nsm_lookup_addr(&ln->nsm_handles, sap);

- if (cached != NULL) {
+ if (cached) {
atomic_inc(&cached->sm_count);
spin_unlock(&nsm_lock);
kfree(new);
@@ -345,7 +345,7 @@ struct nsm_handle *nsm_get_handle(const struct net *net,
return cached;
}

- if (new != NULL) {
+ if (new) {
list_add(&new->sm_link, &ln->nsm_handles);
spin_unlock(&nsm_lock);
dprintk("lockd: created nsm_handle for %s (%s)\n",
@@ -356,7 +356,7 @@ struct nsm_handle *nsm_get_handle(const struct net *net,
spin_unlock(&nsm_lock);

new = nsm_create_handle(sap, salen, hostname, hostname_len);
- if (unlikely(new == NULL))
+ if (unlikely(!new))
return NULL;
goto retry;
}
@@ -379,7 +379,7 @@ struct nsm_handle *nsm_reboot_lookup(const struct net *net,
spin_lock(&nsm_lock);

cached = nsm_lookup_priv(&ln->nsm_handles, &info->priv);
- if (unlikely(cached == NULL)) {
+ if (unlikely(!cached)) {
spin_unlock(&nsm_lock);
dprintk("lockd: never saw rebooted peer '%.*s' before\n",
info->len, info->mon);
@@ -496,7 +496,7 @@ static int nsm_xdr_dec_stat_res(struct rpc_rqst *rqstp,
__be32 *p;

p = xdr_inline_decode(xdr, 4 + 4);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
return -EIO;
resp->status = be32_to_cpup(p++);
resp->state = be32_to_cpup(p);
@@ -514,7 +514,7 @@ static int nsm_xdr_dec_stat(struct rpc_rqst *rqstp,
__be32 *p;

p = xdr_inline_decode(xdr, 4);
- if (unlikely(p == NULL))
+ if (unlikely(!p))
return -EIO;
resp->state = be32_to_cpup(p);

diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index 726b6cecf430..8a5d894a4f07 100644
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -190,7 +190,7 @@ static int create_lockd_listener(struct svc_serv *serv, const char *name,
struct svc_xprt *xprt;

xprt = svc_find_xprt(serv, name, net, family, 0);
- if (xprt == NULL)
+ if (!xprt)
return svc_create_xprt(serv, name, net, family, port,
SVC_SOCK_DEFAULTS);
svc_xprt_put(xprt);
@@ -699,7 +699,7 @@ static int __init init_nlm(void)
#ifdef CONFIG_SYSCTL
err = -ENOMEM;
nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
- if (nlm_sysctl_table == NULL)
+ if (!nlm_sysctl_table)
goto err_sysctl;
#endif
err = register_pernet_subsys(&lockd_net_ops);
diff --git a/fs/lockd/svc4proc.c b/fs/lockd/svc4proc.c
index 82925f17ec45..b16bdd33e5b8 100644
--- a/fs/lockd/svc4proc.c
+++ b/fs/lockd/svc4proc.c
@@ -38,7 +38,7 @@ nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
*hostp = host;

/* Obtain file pointer. Not used by FREE_ALL call. */
- if (filp != NULL) {
+ if (filp) {
if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
goto no_locks;
*filp = file;
@@ -285,12 +285,12 @@ static __be32 nlm4svc_callback(struct svc_rqst *rqstp, u32 proc,
host = nlmsvc_lookup_host(rqstp,
argp->lock.caller,
argp->lock.len);
- if (host == NULL)
+ if (!host)
return rpc_system_err;

call = nlm_alloc_call(host);
nlmsvc_release_host(host);
- if (call == NULL)
+ if (!call)
return rpc_system_err;

stat = func(rqstp, &call->a_res);
diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index 3507c80d1d4b..8f1c058f16b3 100644
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -220,12 +220,12 @@ nlmsvc_create_block(struct svc_rqst *rqstp, struct nlm_host *host,
struct nlm_rqst *call = NULL;

call = nlm_alloc_call(host);
- if (call == NULL)
+ if (!call)
return NULL;

/* Allocate memory for block, and initialize arguments */
block = kzalloc(sizeof(*block), GFP_KERNEL);
- if (block == NULL)
+ if (!block)
goto failed;
kref_init(&block->b_count);
INIT_LIST_HEAD(&block->b_list);
@@ -299,7 +299,7 @@ static void nlmsvc_free_block(struct kref *kref)

static void nlmsvc_release_block(struct nlm_block *block)
{
- if (block != NULL)
+ if (block)
kref_put_mutex(&block->b_count, nlmsvc_free_block, &block->b_file->f_mutex);
}

@@ -381,7 +381,7 @@ nlmsvc_defer_lock_rqst(struct svc_rqst *rqstp, struct nlm_block *block)
if (rqstp->rq_chandle.defer) {
block->b_deferred_req =
rqstp->rq_chandle.defer(block->b_cache_req);
- if (block->b_deferred_req != NULL)
+ if (block->b_deferred_req)
status = nlm_drop_reply;
}
dprintk("lockd: nlmsvc_defer_lock_rqst block %p flags %d status %d\n",
@@ -417,10 +417,10 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file,
* or create new block
*/
block = nlmsvc_lookup_block(file, lock);
- if (block == NULL) {
+ if (!block) {
block = nlmsvc_create_block(rqstp, host, file, lock, cookie);
ret = nlm_lck_denied_nolocks;
- if (block == NULL)
+ if (!block)
goto out;
lock = &block->b_call->a_args.lock;
} else
@@ -606,7 +606,7 @@ nlmsvc_cancel_blocked(struct net *net, struct nlm_file *file, struct nlm_lock *l
mutex_lock(&file->f_mutex);
block = nlmsvc_lookup_block(file, lock);
mutex_unlock(&file->f_mutex);
- if (block != NULL) {
+ if (block) {
vfs_cancel_lock(block->b_file->f_file,
&block->b_call->a_args.lock.fl);
status = nlmsvc_unlink_block(block);
diff --git a/fs/lockd/svcproc.c b/fs/lockd/svcproc.c
index 07915162581d..548f732c8f8e 100644
--- a/fs/lockd/svcproc.c
+++ b/fs/lockd/svcproc.c
@@ -67,7 +67,7 @@ nlmsvc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
*hostp = host;

/* Obtain file pointer. Not used by FREE_ALL call. */
- if (filp != NULL) {
+ if (filp) {
error = cast_status(nlm_lookup_file(rqstp, &file, &lock->fh));
if (error != 0)
goto no_locks;
@@ -326,12 +326,12 @@ static __be32 nlmsvc_callback(struct svc_rqst *rqstp, u32 proc,
host = nlmsvc_lookup_host(rqstp,
argp->lock.caller,
argp->lock.len);
- if (host == NULL)
+ if (!host)
return rpc_system_err;

call = nlm_alloc_call(host);
nlmsvc_release_host(host);
- if (call == NULL)
+ if (!call)
return rpc_system_err;

stat = func(rqstp, &call->a_res);
diff --git a/fs/lockd/svcshare.c b/fs/lockd/svcshare.c
index b0ae07008700..84b54efee9b6 100644
--- a/fs/lockd/svcshare.c
+++ b/fs/lockd/svcshare.c
@@ -41,7 +41,7 @@ nlmsvc_share_file(struct nlm_host *host, struct nlm_file *file,

share = kmalloc(sizeof(*share) + oh->len,
GFP_KERNEL);
- if (share == NULL)
+ if (!share)
return nlm_lck_denied_nolocks;

/* Copy owner handle */
diff --git a/fs/lockd/svcsubs.c b/fs/lockd/svcsubs.c
index a563ddbc19e6..507b4c3ff103 100644
--- a/fs/lockd/svcsubs.c
+++ b/fs/lockd/svcsubs.c
@@ -331,8 +331,7 @@ nlmsvc_mark_host(void *data, struct nlm_host *hint)
{
struct nlm_host *host = data;

- if ((hint->net == NULL) ||
- (host->net == hint->net))
+ if (!hint->net || host->net == hint->net)
host->h_inuse = 1;
return 0;
}
--
2.14.0