Commit 4d62121c authored by Marc Zyngier's avatar Marc Zyngier
Browse files

KVM: arm64: vgic-debug: Avoid dereferencing NULL ITE pointer 



Dan reports that iterating over a device ITEs can legitimately lead
to a NULL pointer, and that the NULL check is placed *after* the
pointer has already been dereferenced.

Hoist the pointer check as early as possible and be done with it.

Reported-by: default avatarDan Carpenter <dan.carpenter@linaro.org>
Fixes: 30deb51a ("KVM: arm64: vgic-its: Add debugfs interface to expose ITS tables")
Link: https://lore.kernel.org/r/aDBylI1YnjPatAbr@stanley.mountain
Cc: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20250530091647.1152489-1-maz@kernel.org


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent 07212d16

arch/arm64/kvm/vgic/vgic-debug.c

+4 −1
Original line number Diff line number Diff line
@@ -490,6 +490,9 @@ static int vgic_its_debug_show(struct seq_file *s, void *v) 
	struct its_device *dev = iter->dev;

	struct its_ite *ite = iter->ite;



	if (!ite)

		return 0;



	if (list_is_first(&ite->ite_list, &dev->itt_head)) {

		seq_printf(s, "\n");

		seq_printf(s, "Device ID: 0x%x, Event ID Range: [0 - %llu]\n",
@@ -498,7 +501,7 @@ static int vgic_its_debug_show(struct seq_file *s, void *v) 
		seq_printf(s, "-----------------------------------------------\n");

	}



	if (ite && ite->irq && ite->collection) {

	if (ite->irq && ite->collection) {

		seq_printf(s, "%8u %8u %8u %8u %8u %2d\n",

			   ite->event_id, ite->irq->intid, ite->irq->hwintid,

			   ite->collection->target_addr,