diff options
Diffstat (limited to 'drivers/isdn')
-rw-r--r-- | drivers/isdn/capi/capi.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/drivers/isdn/capi/capi.c b/drivers/isdn/capi/capi.c index 3c3ad42f22bf..c92b405b7646 100644 --- a/drivers/isdn/capi/capi.c +++ b/drivers/isdn/capi/capi.c @@ -688,6 +688,9 @@ capi_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos if (!cdev->ap.applid) return -ENODEV; + if (count < CAPIMSG_BASELEN) + return -EINVAL; + skb = alloc_skb(count, GFP_USER); if (!skb) return -ENOMEM; @@ -698,7 +701,8 @@ capi_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos } mlen = CAPIMSG_LEN(skb->data); if (CAPIMSG_CMD(skb->data) == CAPI_DATA_B3_REQ) { - if ((size_t)(mlen + CAPIMSG_DATALEN(skb->data)) != count) { + if (count < CAPI_DATA_B3_REQ_LEN || + (size_t)(mlen + CAPIMSG_DATALEN(skb->data)) != count) { kfree_skb(skb); return -EINVAL; } @@ -711,6 +715,10 @@ capi_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos CAPIMSG_SETAPPID(skb->data, cdev->ap.applid); if (CAPIMSG_CMD(skb->data) == CAPI_DISCONNECT_B3_RESP) { + if (count < CAPI_DISCONNECT_B3_RESP_LEN) { + kfree_skb(skb); + return -EINVAL; + } mutex_lock(&cdev->lock); capincci_free(cdev, CAPIMSG_NCCI(skb->data)); mutex_unlock(&cdev->lock); |