The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x a25bc8486f9c01c1af6b6c5657234b2eee2c39d6 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2023042349-cackle-parasite-ff0b@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

a25bc8486f9c ("KVM: arm64: Fix buffer overflow in kvm_arm_set_fw_reg()") 85fbe08e4da8 ("KVM: arm64: Factor out firmware register handling from psci.c") 1ebdbeb03efe ("Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From a25bc8486f9c01c1af6b6c5657234b2eee2c39d6 Mon Sep 17 00:00:00 2001 From: Dan Carpenter dan.carpenter@linaro.org Date: Wed, 19 Apr 2023 13:16:13 +0300 Subject: [PATCH] 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: 99adb567632b ("KVM: arm/arm64: Add save/restore support for firmware workaround state") Signed-off-by: Dan Carpenter dan.carpenter@linaro.org Reviewed-by: Steven Price steven.price@arm.com Reviewed-by: Eric Auger eric.auger@redhat.com Reviewed-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/4efbab8c-640f-43b2-8ac6-6d68e08280fe@kili.mountain Signed-off-by: Oliver Upton oliver.upton@linux.dev

diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c index 5da884e11337..c4b4678bc4a4 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;