Commit a25bc848 authored by Dan Carpenter's avatar Dan Carpenter Committed by Oliver Upton
Browse files

KVM: arm64: Fix buffer overflow in kvm_arm_set_fw_reg() 



The KVM_REG_SIZE() comes from the ioctl and it can be a power of two
between 0-32768 but if it is more than sizeof(long) this will corrupt
memory.

Fixes: 99adb567 ("KVM: arm/arm64: Add save/restore support for firmware workaround state")
Signed-off-by: default avatarDan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: default avatarSteven Price <steven.price@arm.com>
Reviewed-by: default avatarEric Auger <eric.auger@redhat.com>
Reviewed-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/4efbab8c-640f-43b2-8ac6-6d68e08280fe@kili.mountain


Signed-off-by: default avatarOliver Upton <oliver.upton@linux.dev>
parent 35dcb3ac

arch/arm64/kvm/hypercalls.c

+2 −0
Original line number Diff line number Diff line
@@ -397,6 +397,8 @@ int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) 
	u64 val;

	int wa_level;



	if (KVM_REG_SIZE(reg->id) != sizeof(val))

		return -ENOENT;

	if (copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id)))

		return -EFAULT;