From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f175.google.com (mail-pf1-f175.google.com [209.85.210.175]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 70F283DFC6C for ; Thu, 4 Jun 2026 11:18:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.175 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780571902; cv=none; b=XDtIqd5Ox+C7qIhn99tw6WHutrE0uyao/7sUlUrGkw9ntRv+GGyvsIiScI1wxCrW5MnZRlE2pTdh3vrt3sVvhyNxIV+H3z9GjzjC+aCnJa3YPCh0D6YV4mGVF9oW+LQzaOHVcqTKEQeh33U7BhOU3y5bzOc/bcsLRVivlJCEGVM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780571902; c=relaxed/simple; bh=oQQYnWM9INdi1ZTbqVbL5h4zBW7u4UBNoYl/OHAg2tQ=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition; b=eaGpVKy+FJmDx8G/rCaenlZQ0kDYwRz7rjI1X+wazNdfADnj5czNA7r1qrO0M08wF3YBdqzU/yhgAgQnTWmAsTxvqcAS+TQqq4vj5xm9YqQKstC3bWMdzJNnm8L1X6yU8FVA3sDk2fUly0j/pQWz/R5Rw9l5WM0S4a6iveywiCU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=kGgInaQ5; arc=none smtp.client-ip=209.85.210.175 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="kGgInaQ5" Received: by mail-pf1-f175.google.com with SMTP id d2e1a72fcca58-8422524cb38so180584b3a.0 for ; Thu, 04 Jun 2026 04:18:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1780571901; x=1781176701; darn=lists.linux.dev; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :from:to:cc:subject:date:message-id:reply-to; bh=E754gsHGdqu9cYnGBXFWaqxUdZJy8hipJqDVrahb1e4=; b=kGgInaQ53foTsz4FhAuCqm/3s5RXgVpH4ShcIBR36i5g6EsVWLVqV+TroaqCb+e9hK VuaBUV+RDsOXm8tqJiKoLBPWhmKLLYGjYmQFC+/iJ+oVaCVz6nPntKV9xNpWRO/E/INJ aVYnXYDNRQmbyk1p1FzLjWIbnGCKufiZVYUGjnCtulK/gw4AljVta5f99fJgzMi4Ix97 IGvBo+uqjBpeJEeJ9c/vuNOeIJCpxnzXlmenc2WPT1ZX5gePbssu3SVj29yLXEVC74yd tldEjr9Y08+L6xpfQSOeikBygOHSLzVLlPmgR+JDg5yf68aMZNjMwekFNlgZPe8Z8zcG WbDg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780571901; x=1781176701; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=E754gsHGdqu9cYnGBXFWaqxUdZJy8hipJqDVrahb1e4=; b=fHJJTEDSciJJFHZ/oO1THi8+MLqT3LpDtjGyqT37LT4ZNCJLnLxMRQ4husnyzDGO9f zokg9trW0EtGbZBer6s6/WuVWa15A6uU6HvC2h8IMGO4yb2GqaJRXsXgUZHKZxJyOc01 ii/wf5k0wS4aTPcgmXIbKYvbbgkAvlsxGfejqM0dXLWKEmYSvJNGddm8NFC69FJtIV5A bs1VazgMYxxyT7mh7/P9ISEXi90nr2mn2la4hiUIbi99pm716vsFfaA1eds6CUmsHEqc GEWrWlqoDVah0m/UpIGPVGufUI51K8gB0D5orUVcnhOZ+8r1UBMl+7b3jSn6QiO8qQAb xORQ== X-Forwarded-Encrypted: i=1; AFNElJ/VEwb+7snj8jwKh9GkFLa93htic3F7z10PzhyJEvu01gsoz+u8TO0/SzgRtuJ+c8BHKosc+YA=@lists.linux.dev X-Gm-Message-State: AOJu0Yy+ZFJVaKG1sRC++S3QUCHHoq3m38RzLEP43OrgsDztgrk8mOWY IUoq76CaC+ZM+AbG5RjZm72k4Gujs/puwGv077h9C7ih0cKH/UHjHKLY X-Gm-Gg: Acq92OFaRYCaN41E5tQw0u+wGk/5vh/fSS3qH5h3loXsrgdPLA3OpgN9tlL9KjjqIwu oSw1orStAe3akygSb3toBV+7M9zxhz54ZI0GQPU5QHaH5spV+9auLLEcoSDw9Sk/hH7ezzxLNgr J3pwxw5U0UurltpmHFTbveI6y5CWn4s5zwveAfWVxYjbgai+8xpDwQNg4EaSsll77+ZJCx0TgRP yb/i9ryyEQn3fAZWSEIl9KVEMzu3rJqAYYTj20RC24+VgSdjHiz4YCdfKhKVYq9al+cGEWg71Y1 2c+f3X27hVNWkVVEzxWdYydVCmScC4LIWVSUm6rq89ZiJByXD+2LAJr7mAcAuKlMyr3y3aok1j8 PJaRyi9h08TlqVlSF72YsWvrodiKH1mHenF7cWrUAZ6y3sh/tSYfmyUSzDE6RX2BGlKEYZyZIQn y3yCYGjsKEzrnB9OYNKk0lv1sWGk+8PSMYXfWw+GnOwgMI7Zp4vYSpAA== X-Received: by 2002:a05:6a00:3e12:b0:842:672e:7b5d with SMTP id d2e1a72fcca58-84284e32751mr7351126b3a.17.1780571900576; Thu, 04 Jun 2026 04:18:20 -0700 (PDT) Received: from v4bel ([58.123.110.97]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-842828fa877sm5963698b3a.51.2026.06.04.04.18.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 04 Jun 2026 04:18:20 -0700 (PDT) Date: Thu, 4 Jun 2026 20:18:16 +0900 From: Hyunwoo Kim To: maz@kernel.org, oupton@kernel.org, joey.gouly@arm.com, seiden@linux.ibm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, imv4bel@gmail.com Subject: [PATCH] KVM: arm64: Sanitise host vCPU fields in flush_hyp_vcpu() Message-ID: Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline flush_hyp_vcpu() copies the host vCPU context and vGIC state into the hyp's private vCPU on every run. ctxt_to_vcpu() expects a guest context to have a NULL __hyp_running_vcpu, which is only ever set on the host context, so that it resolves the vCPU via container_of(). The vGIC list register save and restore expect used_lrs to stay within the number of implemented list registers. While this is generally the case, flush_hyp_vcpu() copies both fields verbatim from the host vCPU and enforces neither expectation. Fix by clearing __hyp_running_vcpu and clamping used_lrs after the copy. Fixes: be66e67f1750 ("KVM: arm64: Use the pKVM hyp vCPU structure in handle___kvm_vcpu_run()") Signed-off-by: Hyunwoo Kim --- arch/arm64/kvm/hyp/nvhe/hyp-main.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c index 06db299c37a89..ef9318ff0c25e 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -7,6 +7,7 @@ #include #include +#include #include #include #include @@ -128,6 +129,9 @@ static void flush_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu) hyp_vcpu->vcpu.arch.ctxt = host_vcpu->arch.ctxt; + /* A guest context must keep a NULL __hyp_running_vcpu. */ + hyp_vcpu->vcpu.arch.ctxt.__hyp_running_vcpu = NULL; + hyp_vcpu->vcpu.arch.mdcr_el2 = host_vcpu->arch.mdcr_el2; hyp_vcpu->vcpu.arch.hcr_el2 &= ~(HCR_TWI | HCR_TWE); hyp_vcpu->vcpu.arch.hcr_el2 |= READ_ONCE(host_vcpu->arch.hcr_el2) & @@ -139,6 +143,13 @@ static void flush_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu) hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3 = host_vcpu->arch.vgic_cpu.vgic_v3; + /* Bound the host-provided used_lrs by the implemented list registers. */ + if (static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) + hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3.used_lrs = + min_t(unsigned int, + hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3.used_lrs, + (read_gicreg(ICH_VTR_EL2) & 0xf) + 1); + hyp_vcpu->vcpu.arch.pid = host_vcpu->arch.pid; } -- 2.43.0