From 8d6a870a428f3164dc437d183077c40e835c8fcb Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Wed, 19 Apr 2023 13:16:13 +0300 Subject: KVM: arm64: Fix buffer overflow in kvm_arm_set_fw_reg() commit a25bc8486f9c01c1af6b6c5657234b2eee2c39d6 upstream. 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: 99adb567632b ("KVM: arm/arm64: Add save/restore support for firmware workaround state") Signed-off-by: Dan Carpenter Reviewed-by: Steven Price Reviewed-by: Eric Auger Reviewed-by: Marc Zyngier Link: https://lore.kernel.org/r/4efbab8c-640f-43b2-8ac6-6d68e08280fe@kili.mountain Signed-off-by: Oliver Upton Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kvm/hypercalls.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/arm64/kvm') diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c index c9f401fa01a9..950e35b993d2 100644 --- a/arch/arm64/kvm/hypercalls.c +++ b/arch/arm64/kvm/hypercalls.c @@ -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; -- cgit v1.2.3