From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DECCA48665E for ; Wed, 30 Sep 2026 23:55:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790812556; cv=none; b=NK6ViJ1F5+0o1zwqpgRQA4oc9EApxkkcioCBM6RRFc9ULyh8voBph4m/LeO1mR+21C8a0M0MYjwm/qX4IGKE7K7Adi5C4moNdFLTUcaF8j2hUjjFpF8fKnZaMqBBOvCaNoGQpckSTFU4m1ixLhIemQpXKECrSQjk48ckeHT1DQQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790812556; c=relaxed/simple; bh=CLGtJSAUENs2VTQ53y7eNwVZpCXBVwE0yrVUflRgCzs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nqVZ29Dyk3NF1uPIwNHBcRHEg+KFFDcl4Bh4+lihYg6u3DWANvIbe5YeQb3IjS4K12gb25Q39k2hZtxOFh7QCGksFRbgio+oTTnaHqbBhyZv6oelE0vCvH2eQCl1xGzzwr1bHnE6H+H/bmZew1lXUTRQ0r/w2O/NqvHc7FEYxNk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IlZp9JgI; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="IlZp9JgI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3CE881F00899; Wed, 30 Sep 2026 23:55:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790812554; bh=UB/C0Yro6uUSy/4p6PnVYyY7zOfgN45lrHW3TQ8oUTk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=IlZp9JgIQ7ANumtu1RuH7B5m7vTsDKAf4D7zJdiA9tMW+lN/lgC2y5CceS5Sqwng7 4ksZKG1OaQPxEml6Iot30QCGS6adIofjNy/gOV5taewLsFwJFUGCGcFkALA3Es78lb t9dpYLIopHCbWAUhY4nDSj1pRBRWFVf7gwaqgh8V4124bj93mH9i5HfMsNWhizo9Se HeqEwOrIHG4vZO+dGEC0Re/di6iAE3YpOBUPKkpbb50Pu0CUCCHE0v6n+SmCa6+MJs kaI999B/wI+XpSpDowKaA996iYvPLyIAA9fEnLsxyMW9PaX0YKalDoKs8ts7sNq7ka Oj02HqTZsIwLQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Sean Christopherson , Jinwoo Lee , Stefan Teodorescu , Sasha Levin Subject: [PATCH 5.15.y 2/2] KVM: x86: Re-pend GET_NESTED_STATE_PAGES if getting said pages fails Date: Wed, 30 Sep 2026 19:55:51 -0400 Message-ID: <20260930235551.1345464-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260930235551.1345464-1-sashal@kernel.org> References: <2026092947-deflector-impound-8267@gregkh> <20260930235551.1345464-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Sean Christopherson [ Upstream commit 10180a277549339020b08000206092c07e0bff5a ] Re-pend GET_NESTED_STATE_PAGES before exiting to userspace if getting the nested pages fails in the KVM_RUN path. If userspace re-runs the vCPU, and vmcs02 holds valid PFNs from the *previous* run of L2, then KVM could re-enter L2 with stale, unpinned PFNs mapped into e.g. the vAPIC page. Note, both SVM and VMX (as of commit 11722439fb20 ("KVM: nVMX: Ensure KVM_REQ_GET_NESTED_STATE_PAGES is cleared on VM-Exit") ensure the request is cleared on VM-Exit (including the "forced" case), i.e. there is no risk of double-mapping due to emulated VMLAUNCH/VMRESUME/VMRUN *and* the request trying to map the nested pages. Fixes: 671ddc700fd0 ("KVM: nVMX: Don't leak L1 MMIO regions to L2") Cc: stable@vger.kernel.org Reported-by: Jinwoo Lee Closes: https://lore.kernel.org/all/20260813043932.3214460-1-rkskek9254@gmail.com Reported-by: Stefan Teodorescu Link: https://patch.msgid.link/20260921211608.1030158-2-seanjc@google.com Signed-off-by: Sean Christopherson Signed-off-by: Sasha Levin --- arch/x86/kvm/x86.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 30a9a9fd04aaa..c7a9203a60c96 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9779,6 +9779,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) if (kvm_check_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu)) { if (unlikely(!kvm_nested_call(get_nested_state_pages)(vcpu))) { + kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu); r = 0; goto out; } -- 2.53.0