[OPENPROMIO]: Handle current_node being NULL correctly.

If the user tries to traverse to the next node of the
last node, we get NULL in current_node and a zero phandle
returned.  That's fine, but if the user tries to obtain
properties in that state, we try to dereference a NULL
pointer in the downcall to the of_*() routines.

So protect against that.

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2006-09-18 01:47:13 -07:00
parent 803db244b9
commit b9b64e6e89

View file

@ -145,8 +145,9 @@ static int opromgetprop(void __user *argp, struct device_node *dp, struct openpr
void *pval;
int len;
pval = of_get_property(dp, op->oprom_array, &len);
if (!pval || len <= 0 || len > bufsize)
if (!dp ||
!(pval = of_get_property(dp, op->oprom_array, &len)) ||
len <= 0 || len > bufsize)
return copyout(argp, op, sizeof(int));
memcpy(op->oprom_array, pval, len);
@ -161,6 +162,8 @@ static int opromnxtprop(void __user *argp, struct device_node *dp, struct openpr
struct property *prop;
int len;
if (!dp)
return copyout(argp, op, sizeof(int));
if (op->oprom_array[0] == '\0') {
prop = dp->properties;
if (!prop)
@ -266,9 +269,13 @@ static int oprompci2node(void __user *argp, struct device_node *dp, struct openp
static int oprompath2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
{
phandle ph = 0;
dp = of_find_node_by_path(op->oprom_array);
if (dp)
ph = dp->node;
data->current_node = dp;
*((int *)op->oprom_array) = dp->node;
*((int *)op->oprom_array) = ph;
op->oprom_size = sizeof(int);
return copyout(argp, op, bufsize + sizeof(int));