Commit 8fbaa51d authored Jul 15, 2016 by Andrew Donnellan Committed by Michael Ellerman Jul 19, 2016

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: 14baf4d9 ("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>

parent 1e44727a

drivers/misc/cxl/guest.c

+9 −7

Original line number	Diff line number	Diff line
		@@ -1055,6 +1055,7 @@ static void free_adapter(struct cxl *adapter)
		struct irq_avail *cur;
		int i;

		if (adapter->guest) {
		if (adapter->guest->irq_avail) {
		for (i = 0; i < adapter->guest->irq_nranges; i++) {
		cur = &adapter->guest->irq_avail[i];
		@@ -1063,8 +1064,9 @@ static void free_adapter(struct cxl *adapter)
		kfree(adapter->guest->irq_avail);
		}
		kfree(adapter->guest->status);
		cxl_remove_adapter_nr(adapter);
		kfree(adapter->guest);
		}
		cxl_remove_adapter_nr(adapter);
		kfree(adapter);
		}

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