This is a note to let you know that I've just added the patch titled
KVM: SVM: Return -EFAULT if copy_to_user() for SEV mig packet header fails
to the 5.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kvm-svm-return-efault-if-copy_to_user-for-sev-mig-pa.patch
and it can be found in the queue-5.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit b43a089c497e506ba3b8c957d51a4df87c8938dc
Author: Sean Christopherson <seanjc@xxxxxxxxxx>
Date: Thu May 6 10:58:25 2021 -0700
KVM: SVM: Return -EFAULT if copy_to_user() for SEV mig packet header fails
[ Upstream commit b4a693924aab93f3747465b2261add46c82c3220 ]
Return -EFAULT if copy_to_user() fails; if accessing user memory faults,
copy_to_user() returns the number of bytes remaining, not an error code.
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Cc: Steve Rutherford <srutherford@xxxxxxxxxx>
Cc: Brijesh Singh <brijesh.singh@xxxxxxx>
Cc: Ashish Kalra <ashish.kalra@xxxxxxx>
Fixes: d3d1af85e2c7 ("KVM: SVM: Add KVM_SEND_UPDATE_DATA command")
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Message-Id: <20210506175826.2166383-2-seanjc@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 8d36f0c73071..3dc3e2897804 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -1309,8 +1309,9 @@ static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp)
}
/* Copy packet header to userspace. */
- ret = copy_to_user((void __user *)(uintptr_t)params.hdr_uaddr, hdr,
- params.hdr_len);
+ if (copy_to_user((void __user *)(uintptr_t)params.hdr_uaddr, hdr,
+ params.hdr_len))
+ ret = -EFAULT;
e_free_trans_data:
kfree(trans_data);
