[ISDN]: Static overruns in drivers/isdn/i4l/isdn_ppp.c

Coverity found some static overruns in isdn_ppp.c (bug id #519) At several
places slot is compared <0 and > ISDN_MAX_CHANNELS and then used to index
ippp_table[ISDN_MAX_CHANNELS] A value of slot = ISDN_MAX_CHANNELS would run
over the end of the array.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/isdn/i4l/isdn_ppp.c b/drivers/isdn/i4l/isdn_ppp.c
index a0927d1..9187422 100644 (file)
--- a/drivers/isdn/i4l/isdn_ppp.c
+++ b/drivers/isdn/i4l/isdn_ppp.c
@@ -109,7 +109,7 @@ isdn_ppp_free(isdn_net_local * lp)
 {
        struct ippp_struct *is;
 
-       if (lp->ppp_slot < 0 || lp->ppp_slot > ISDN_MAX_CHANNELS) {
+       if (lp->ppp_slot < 0 || lp->ppp_slot >= ISDN_MAX_CHANNELS) {
                printk(KERN_ERR "%s: ppp_slot(%d) out of range\n",
                        __FUNCTION__, lp->ppp_slot);
                return 0;
@@ -126,7 +126,7 @@ isdn_ppp_free(isdn_net_local * lp)
        lp->netdev->pb->ref_ct--;
        spin_unlock(&lp->netdev->pb->lock);
 #endif /* CONFIG_ISDN_MPP */
-       if (lp->ppp_slot < 0 || lp->ppp_slot > ISDN_MAX_CHANNELS) {
+       if (lp->ppp_slot < 0 || lp->ppp_slot >= ISDN_MAX_CHANNELS) {
                printk(KERN_ERR "%s: ppp_slot(%d) now invalid\n",
                        __FUNCTION__, lp->ppp_slot);
                return 0;
@@ -279,7 +279,7 @@ isdn_ppp_open(int min, struct file *file)
        int slot;
        struct ippp_struct *is;
 
-       if (min < 0 || min > ISDN_MAX_CHANNELS)
+       if (min < 0 || min >= ISDN_MAX_CHANNELS)
                return -ENODEV;
 
        slot = isdn_ppp_get_slot();
@@ -1042,7 +1042,7 @@ isdn_ppp_push_higher(isdn_net_dev * net_dev, isdn_net_local * lp, struct sk_buff
        if (lp->master) { // FIXME?
                mlp = (isdn_net_local *) lp->master->priv;
                slot = mlp->ppp_slot;
-               if (slot < 0 || slot > ISDN_MAX_CHANNELS) {
+               if (slot < 0 || slot >= ISDN_MAX_CHANNELS) {
                        printk(KERN_ERR "isdn_ppp_push_higher: master->ppp_slot(%d)\n",
                                lp->ppp_slot);
                        goto drop_packet;
@@ -1264,7 +1264,7 @@ isdn_ppp_xmit(struct sk_buff *skb, struct net_device *netdev)
        /* we have our lp locked from now on */
 
        slot = lp->ppp_slot;
-       if (slot < 0 || slot > ISDN_MAX_CHANNELS) {
+       if (slot < 0 || slot >= ISDN_MAX_CHANNELS) {
                printk(KERN_ERR "isdn_ppp_xmit: lp->ppp_slot(%d)\n",
                        lp->ppp_slot);
                kfree_skb(skb);
@@ -1603,7 +1603,7 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp,
        mp = net_dev->pb;
         stats = &mp->stats;
        slot = lp->ppp_slot;
-       if (slot < 0 || slot > ISDN_MAX_CHANNELS) {
+       if (slot < 0 || slot >= ISDN_MAX_CHANNELS) {
                printk(KERN_ERR "%s: lp->ppp_slot(%d)\n",
                        __FUNCTION__, lp->ppp_slot);
                stats->frame_drops++;
@@ -1640,7 +1640,7 @@ static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp,
        is->last_link_seqno = minseq = newseq;
        for (lpq = net_dev->queue;;) {
                slot = lpq->ppp_slot;
-               if (slot < 0 || slot > ISDN_MAX_CHANNELS) {
+               if (slot < 0 || slot >= ISDN_MAX_CHANNELS) {
                        printk(KERN_ERR "%s: lpq->ppp_slot(%d)\n",
                                __FUNCTION__, lpq->ppp_slot);
                } else {
@@ -2648,7 +2648,7 @@ static void isdn_ppp_receive_ccp(isdn_net_dev *net_dev, isdn_net_local *lp,
 
        printk(KERN_DEBUG "Received CCP frame from peer slot(%d)\n",
                lp->ppp_slot);
-       if (lp->ppp_slot < 0 || lp->ppp_slot > ISDN_MAX_CHANNELS) {
+       if (lp->ppp_slot < 0 || lp->ppp_slot >= ISDN_MAX_CHANNELS) {
                printk(KERN_ERR "%s: lp->ppp_slot(%d) out of range\n",
                        __FUNCTION__, lp->ppp_slot);
                return;
@@ -2658,7 +2658,7 @@ static void isdn_ppp_receive_ccp(isdn_net_dev *net_dev, isdn_net_local *lp,
 
        if(lp->master) {
                int slot = ((isdn_net_local *) (lp->master->priv))->ppp_slot;
-               if (slot < 0 || slot > ISDN_MAX_CHANNELS) {
+               if (slot < 0 || slot >= ISDN_MAX_CHANNELS) {
                        printk(KERN_ERR "%s: slot(%d) out of range\n",
                                __FUNCTION__, slot);
                        return;
@@ -2845,7 +2845,7 @@ static void isdn_ppp_send_ccp(isdn_net_dev *net_dev, isdn_net_local *lp, struct
 
        if (lp->master) {
                slot = ((isdn_net_local *) (lp->master->priv))->ppp_slot;
-               if (slot < 0 || slot > ISDN_MAX_CHANNELS) {
+               if (slot < 0 || slot >= ISDN_MAX_CHANNELS) {
                        printk(KERN_ERR "%s: slot(%d) out of range\n",
                                __FUNCTION__, slot);
                        return;