[WAN]: kfree of NULL pointer is valid

kfree(0) is perfectly valid, checking pointers for NULL before calling 
kfree() on them is redundant. The patch below cleans away a few such 
redundant checks (and while I was around some of those bits I couldn't 
stop myself from making a few tiny whitespace changes as well).

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Acked-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 23 insertions, 45 deletions

diff --git a/drivers/net/wan/cycx_x25.c b/drivers/net/wan/cycx_x25.c
index 5b48cd8568f5..02d57c0b4243 100644
--- a/drivers/net/wan/cycx_x25.c
+++ b/drivers/net/wan/cycx_x25.c
@@ -436,9 +436,7 @@ static int cycx_wan_new_if(struct wan_device *wandev, struct net_device *dev,
         }
 
         if (err) {
-                if (chan->local_addr)
-                        kfree(chan->local_addr);
-
+                kfree(chan->local_addr);
                 kfree(chan);
                 return err;
         }
@@ -458,9 +456,7 @@ static int cycx_wan_del_if(struct wan_device *wandev, struct net_device *dev)
                 struct cycx_x25_channel *chan = dev->priv;
 
                 if (chan->svc) {
-                        if (chan->local_addr)
-                                kfree(chan->local_addr);
-
+                        kfree(chan->local_addr);
                         if (chan->state == WAN_CONNECTED)
                                 del_timer(&chan->timer);
                 }
diff --git a/drivers/net/wan/pc300_tty.c b/drivers/net/wan/pc300_tty.c
index 29f84ad08730..8454bf6caaa7 100644
--- a/drivers/net/wan/pc300_tty.c
+++ b/drivers/net/wan/pc300_tty.c
@@ -400,10 +400,8 @@ static void cpc_tty_close(struct tty_struct *tty, struct file *flip)
                 cpc_tty->buf_rx.last = NULL;
         }
         
-        if (cpc_tty->buf_tx) {
-                kfree(cpc_tty->buf_tx);
-                cpc_tty->buf_tx = NULL;
-        }
+        kfree(cpc_tty->buf_tx);
+        cpc_tty->buf_tx = NULL;
 
         CPC_TTY_DBG("%s: TTY closed\n",cpc_tty->name);
         
@@ -666,7 +664,7 @@ static void cpc_tty_rx_work(void * data)
         unsigned long port;
         int i, j;
         st_cpc_tty_area *cpc_tty; 
-        volatile st_cpc_rx_buf * buf;
+        volatile st_cpc_rx_buf *buf;
         char flags=0,flg_rx=1; 
         struct tty_ldisc *ld;
 
@@ -680,9 +678,9 @@ static void cpc_tty_rx_work(void * data)
                         cpc_tty = &cpc_tty_area[port];
                 
                         if ((buf=cpc_tty->buf_rx.first) != 0) {
-                                if(cpc_tty->tty) {
+                                if (cpc_tty->tty) {
                                         ld = tty_ldisc_ref(cpc_tty->tty);
-                                        if(ld) {
+                                        if (ld) {
                                                 if (ld->receive_buf) {
                                                         CPC_TTY_DBG("%s: call line disc. receive_buf\n",cpc_tty->name);
                                                         ld->receive_buf(cpc_tty->tty, (char *)(buf->data), &flags, buf->size);
@@ -691,7 +689,7 @@ static void cpc_tty_rx_work(void * data)
                                         }
                                 }       
                                 cpc_tty->buf_rx.first = cpc_tty->buf_rx.first->next;
-                                kfree((unsigned char *)buf);
+                                kfree(buf);
                                 buf = cpc_tty->buf_rx.first;
                                 flg_rx = 1;
                         }
@@ -733,7 +731,7 @@ static void cpc_tty_rx_disc_frame(pc300ch_t *pc300chan)
 
 void cpc_tty_receive(pc300dev_t *pc300dev)
 {
-        st_cpc_tty_area    *cpc_tty; 
+        st_cpc_tty_area *cpc_tty; 
         pc300ch_t *pc300chan = (pc300ch_t *)pc300dev->chan; 
         pc300_t *card = (pc300_t *)pc300chan->card; 
         int ch = pc300chan->channel; 
@@ -742,7 +740,7 @@ void cpc_tty_receive(pc300dev_t *pc300dev)
         int rx_len, rx_aux; 
         volatile unsigned char status; 
         unsigned short first_bd = pc300chan->rx_first_bd;
-        st_cpc_rx_buf   *new=NULL;
+        st_cpc_rx_buf *new = NULL;
         unsigned char dsr_rx;
 
         if (pc300dev->cpc_tty == NULL) { 
@@ -762,7 +760,7 @@ void cpc_tty_receive(pc300dev_t *pc300dev)
                         if (status & DST_EOM) {
                                 break;
                         }
-                        ptdescr=(pcsca_bd_t __iomem *)(card->hw.rambase+cpc_readl(&ptdescr->next));
+                        ptdescr = (pcsca_bd_t __iomem *)(card->hw.rambase+cpc_readl(&ptdescr->next));
                 }
                         
                 if (!rx_len) { 
@@ -771,10 +769,7 @@ void cpc_tty_receive(pc300dev_t *pc300dev)
                                 cpc_writel(card->hw.scabase + DRX_REG(EDAL, ch), 
                                                 RX_BD_ADDR(ch, pc300chan->rx_last_bd)); 
                         }
-                        if (new) {
-                                kfree(new);
-                                new = NULL;
-                        }
+                        kfree(new);
                         return; 
                 }
                 
@@ -787,7 +782,7 @@ void cpc_tty_receive(pc300dev_t *pc300dev)
                         continue;
                 } 
                 
-                new = (st_cpc_rx_buf *) kmalloc(rx_len + sizeof(st_cpc_rx_buf), GFP_ATOMIC);
+                new = (st_cpc_rx_buf *)kmalloc(rx_len + sizeof(st_cpc_rx_buf), GFP_ATOMIC);
                 if (new == 0) {
                         cpc_tty_rx_disc_frame(pc300chan);
                         continue;
diff --git a/drivers/net/wan/sdla_chdlc.c b/drivers/net/wan/sdla_chdlc.c
index afbe0024e3e1..496d29237e92 100644
--- a/drivers/net/wan/sdla_chdlc.c
+++ b/drivers/net/wan/sdla_chdlc.c
@@ -3664,15 +3664,10 @@ static void wanpipe_tty_close(struct tty_struct *tty, struct file * filp)
                 chdlc_disable_comm_shutdown(card);
                 unlock_adapter_irq(&card->wandev.lock,&smp_flags);
 
-                if (card->tty_buf){
-                        kfree(card->tty_buf);
-                        card->tty_buf=NULL;                     
-                }
-
-                if (card->tty_rx){
-                        kfree(card->tty_rx);
-                        card->tty_rx=NULL;
-                }
+                kfree(card->tty_buf);
+                card->tty_buf = NULL;                   
+                kfree(card->tty_rx);
+                card->tty_rx = NULL;
         }
         return;
 }
diff --git a/drivers/net/wan/x25_asy.c b/drivers/net/wan/x25_asy.c
index 8c5cfcb55826..1c540d825551 100644
--- a/drivers/net/wan/x25_asy.c
+++ b/drivers/net/wan/x25_asy.c
@@ -107,13 +107,9 @@ static struct x25_asy *x25_asy_alloc(void)
 static void x25_asy_free(struct x25_asy *sl)
 {
         /* Free all X.25 frame buffers. */
-        if (sl->rbuff)  {
-                kfree(sl->rbuff);
-        }
+        kfree(sl->rbuff);
         sl->rbuff = NULL;
-        if (sl->xbuff)  {
-                kfree(sl->xbuff);
-        }
+        kfree(sl->xbuff);
         sl->xbuff = NULL;
 
         if (!test_and_clear_bit(SLF_INUSE, &sl->flags)) {
@@ -134,10 +130,8 @@ static int x25_asy_change_mtu(struct net_device *dev, int newmtu)
         {
                 printk("%s: unable to grow X.25 buffers, MTU change cancelled.\n",
                        dev->name);
-                if (xbuff != NULL)  
-                        kfree(xbuff);
-                if (rbuff != NULL)  
-                        kfree(rbuff);
+                kfree(xbuff);
+                kfree(rbuff);
                 return -ENOMEM;
         }
 
@@ -169,10 +163,8 @@ static int x25_asy_change_mtu(struct net_device *dev, int newmtu)
 
         spin_unlock_bh(&sl->lock);
 
-        if (xbuff != NULL) 
-                kfree(xbuff);
-        if (rbuff != NULL)
-                kfree(rbuff);
+        kfree(xbuff);
+        kfree(rbuff);
         return 0;
 }