linux-kernel - [PATCH 5.13 044/223] KVM: SVM: Return -EFAULT if copy_to

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210726153847.702458359@linuxfoundation.org>
Date:   Mon, 26 Jul 2021 17:37:16 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Dan Carpenter <dan.carpenter@...cle.com>,
        Steve Rutherford <srutherford@...gle.com>,
        Brijesh Singh <brijesh.singh@....com>,
        Ashish Kalra <ashish.kalra@....com>,
        Sean Christopherson <seanjc@...gle.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.13 044/223] KVM: SVM: Return -EFAULT if copy_to_user() for SEV mig packet header fails

From: Sean Christopherson <seanjc@...gle.com>

[ 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@...cle.com>
Cc: Steve Rutherford <srutherford@...gle.com>
Cc: Brijesh Singh <brijesh.singh@....com>
Cc: Ashish Kalra <ashish.kalra@....com>
Fixes: d3d1af85e2c7 ("KVM: SVM: Add KVM_SEND_UPDATE_DATA command")
Signed-off-by: Sean Christopherson <seanjc@...gle.com>
Message-Id: <20210506175826.2166383-2-seanjc@...gle.com>
Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 arch/x86/kvm/svm/sev.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

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);
-- 
2.30.2