From nobody Wed Jun 17 03:58:51 2026 Received: from mail-wr1-f74.google.com (mail-wr1-f74.google.com [209.85.221.74]) (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 5F8353CD8B6 for ; Wed, 22 Apr 2026 10:25:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.74 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776853559; cv=none; b=P1gBiVByM7wHqzFpuSNqarik+mm6e6bOlnyQDx5A2ung5wwpMS/s1V+55Ui6n0ZraDq9Lb95Z4EPqd0K+5SP8ttaOtoTfBdcSOEESB05LHQZBaAVJHJTNQ4fzTKqlySUiQuXLRM5jquftJrRI/k3KVnwfGbuZJvogdeColNGJLg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776853559; c=relaxed/simple; bh=4e9RR3Fkt5ZYKdTIbJ3Mu4JFWKC86taawCJaNBynDdI=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=dYdto0oDcexG1RguiDdGSejaX0Cm9NSvXKTJOahTN0MRjyLyIm9fv8APRh/XuW0tQphYbBRXcH6PgSayDcWlOIY9DvuQp3kS1wykZVZpe2mEm4UDzZoLJctE32uK8zG6I9JEXnK67MAwTKs9oYjWDoPi7OKt6vfOMjDcJwhKXyI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--sebastianene.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Q/HL9pxb; arc=none smtp.client-ip=209.85.221.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--sebastianene.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Q/HL9pxb" Received: by mail-wr1-f74.google.com with SMTP id ffacd0b85a97d-43d780757eeso3094252f8f.1 for ; Wed, 22 Apr 2026 03:25:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1776853556; x=1777458356; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=5zVG8CK37G2H3h+/vsooWmb/JX2s+XnozBdTiycqzLw=; b=Q/HL9pxbj9fjfJerdkMdihhSQ2Es3zUJ1UQciZSRFoQZb61cDd/FUUksRrwVpTfZW2 MVnFlk9zNhCuc1MWIvdwzybRtZ+chsatmizS+7J/RiAhctWKwSqJUZujedxIvGMHY2Ak zhJMO7MTafnBGD+UqTKTxwc1MHaHzbcivdxFxDlUdtKwu76EP+ek9JAvQpKoAOZTZEM5 5pyT2aDaXjgljGYg7YApUPvNFEQZ+E9AaF3e2K7cSp+K4q+7bohbsr8116JAl2x4HHLa asO452DorM3KKZCrxL3JKwi6ILU3KpFJ9EPeFpKSuOwNG631TPtQ76luXsFysbkR0RQR KT1A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776853556; x=1777458356; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=5zVG8CK37G2H3h+/vsooWmb/JX2s+XnozBdTiycqzLw=; b=Az0CHWKbtNNj6SkErdmsmTZB3pzM4fDglCneM57IMdefoiIFOy2UfL5nNK/zq3Ixk5 OJsJJF6iawEl0O3g+842Bfha/Gqb/LM3esMBfHpsazg3BU/tBJKE3UPGMt+Vo41jdIZl 0/PVYUQAsvGN/8/lo+nTTh84skhSfvd9JnRyuqqjIMVP10cK2dGDdJ06J3cRjletBEgN MKueWCZNYnHgKagShCk2W++60z3O4oWNzB+3DEW1GB1/Nk/bDfVjOGR7M/o55c1VywAF znl0BMPGu4vqcs2qy/zk1QksUdAkzuxdOHLz0cEjHGQ3vmedOu0vEvDAwbeTdu9xk13X TDeg== X-Forwarded-Encrypted: i=1; AFNElJ8tjY8C8vpuKq9a/jIIWhHuJF3W2cclE6jA8qDWpAo1ttS/m7HjDIw9Po7Q5nEkoq8D6yBZ5ZFWy2tQDfA=@vger.kernel.org X-Gm-Message-State: AOJu0YzPXH2JXVmQSY4uJJJeRRKkGGqcP6bJFNZNbsew1hPdoOI45/12 /X/wLYa1DwGWzoedPZJvoRSy4Tw1Yetk+YxLQqZ4c+gXvtBZPtNgwf4lmUVACbi9HamxkANvslx ry7NqLqt3c90TAo4Mke6McVnLS8JLag== X-Received: from wrnl17.prod.google.com ([2002:adf:e9d1:0:b0:43c:ff2f:44d7]) (user=sebastianene job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6000:2812:b0:43d:7192:2ca6 with SMTP id ffacd0b85a97d-43fe407e0eemr21607407f8f.16.1776853555738; Wed, 22 Apr 2026 03:25:55 -0700 (PDT) Date: Wed, 22 Apr 2026 10:25:40 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.54.0.rc1.555.g9c883467ad-goog Message-ID: <20260422102540.1433704-1-sebastianene@google.com> Subject: [PATCH] KVM: arm64: Validate the FF-A memory access descriptor placement From: Sebastian Ene To: maz@kernel.org, oupton@kernel.org, will@kernel.org Cc: ayrton@google.com, catalin.marinas@arm.com, joey.gouly@arm.com, korneld@google.com, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, android-kvm@google.com, mrigendra.chaubey@gmail.com, perlarsen@google.com, sebastianene@google.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, stable@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Prevent the pKVM hypervisor from making assumptions that the endpoint memory access descriptor (EMAD) comes right after the FF-A memory region header and enforce a strict placement for it when validating an FF-A memory lend/share transaction. Prior to FF-A version 1.1 the header of the memory region didn't contain an offset to the endpoint memory access descriptor. The layout of a memory transaction looks like this: Field name | Offset -- 0 [ Header (ffa_mem_region) |__ ep_mem_offset EMAD 1 (ffa_mem_region_attributes) | ] Reject the host from specifying a memory access descriptor offset that is different than the size of the memory region header. Cc: stable@vger.kernel.org Fixes: 42fb33dde42b ("KVM: arm64: Use FF-A 1.1 with pKVM") Signed-off-by: Sebastian Ene --- arch/arm64/kvm/hyp/nvhe/ffa.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c index 94161ea1cd60..0703c0ad8dff 100644 --- a/arch/arm64/kvm/hyp/nvhe/ffa.c +++ b/arch/arm64/kvm/hyp/nvhe/ffa.c @@ -508,6 +508,12 @@ static void __do_ffa_mem_xfer(const u64 func_id, buf =3D hyp_buffers.tx; memcpy(buf, host_buffers.tx, fraglen); =20 + if (FFA_MEM_REGION_HAS_EP_MEM_OFFSET(hyp_ffa_version) && + buf->ep_mem_offset !=3D sizeof(struct ffa_mem_region)) { + ret =3D FFA_RET_INVALID_PARAMETERS; + goto out_unlock; + } + ep_mem_access =3D (void *)buf + ffa_mem_desc_offset(buf, 0, hyp_ffa_version); offset =3D ep_mem_access->composite_off; --=20 2.54.0.rc1.555.g9c883467ad-goog