cxl: fix potential NULL dereference in free_adapter()

If kzalloc() fails when allocating adapter->guest in
cxl_guest_init_adapter(), we call free_adapter() before erroring out.
free_adapter() in turn attempts to dereference adapter->guest, which in
this case is NULL.

In free_adapter(), skip the adapter->guest cleanup if adapter->guest is
NULL.

Fixes: 14baf4d9c7 ("cxl: Add guest-specific code")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Andrew Donnellan 2016-07-15 17:20:36 +10:00 коммит произвёл Michael Ellerman
Родитель 1e44727a0b
Коммит 8fbaa51d43
1 изменённых файлов: 9 добавлений и 7 удалений

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@ -1055,16 +1055,18 @@ static void free_adapter(struct cxl *adapter)
struct irq_avail *cur;
int i;
if (adapter->guest->irq_avail) {
for (i = 0; i < adapter->guest->irq_nranges; i++) {
cur = &adapter->guest->irq_avail[i];
kfree(cur->bitmap);
if (adapter->guest) {
if (adapter->guest->irq_avail) {
for (i = 0; i < adapter->guest->irq_nranges; i++) {
cur = &adapter->guest->irq_avail[i];
kfree(cur->bitmap);
}
kfree(adapter->guest->irq_avail);
}
kfree(adapter->guest->irq_avail);
kfree(adapter->guest->status);
kfree(adapter->guest);
}
kfree(adapter->guest->status);
cxl_remove_adapter_nr(adapter);
kfree(adapter->guest);
kfree(adapter);
}