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 B7A6A42124C for ; Wed, 22 Jul 2026 18:00:57 +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=1784743259; cv=none; b=jZZn5j+DUZDx46qFS6E/S8Cmhi42z4eIfDHUfTpYM5fGnZbnFlv/TrpWyVFNM+iB8urhsGDYbUB7xJnWWlnaXz71Y2GAte8o6+XxL7Abe1XaCHnTEs96HfbxCGdQh4wjCYyr9cQwozd4Ydx0hr/okhnLVcG2lNCSTzpEjGO/7VI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784743259; c=relaxed/simple; bh=zVOWltkIitAhWLCBL00PfpI+7ufeokEF6zqCoJUdCq0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=I+mvRWTcsVLdN2VP0Wk9td9hm7Ju71Y5R2LwgP11KBI3bbNWm4cFzZ61umnXoK34h98Qca9LXmQUjfTpcpzO1U7KD2bZpBONKQ97jP7CFzJREF/MG2o9R9losM6kXISaU0/p0pJsPowPbsbbiUU8GLj6MgRnkn/D3pc1hskO+AQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CRSDZVUc; 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="CRSDZVUc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C80C51F00A3F; Wed, 22 Jul 2026 18:00:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784743257; bh=bGJxQDjW8kMIJzMzY1kBppxzAQot3PL4uIZLUOY/cxU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=CRSDZVUcfRJBKlGMM3mXGzEouDlwIJk+z1sOd4tAKeA41cGs4FTi5PFrAZr1vJM/c YKTFSS1DFZCKNGn+mzmLJOiPNcYXcmZ8kPi4zO8RWpZlwhSOnEPXcQz17BarKSD/d4 998ckP3hRWprWIHVQaFsbEt5L+sfApsI4F6fu0TCgMGKi1pJcYtDG9E3OkVIV2G/UN kKQoDkP5lPCxipg5HoYqzY/rH3QU9kD7ZtbqRUAG/EN3vVjfLW71El9MWekzImSQiH n9JsbDnT/rVxtnmvEWnX771w7uN8qyuZjf4/hcGMzvaooRXHF3Q+FXJ23qYhIsFzyB NEeIH0+c7CjVg== From: Sasha Levin To: stable@vger.kernel.org Cc: Jason Wang , Xie Yongji , =?UTF-8?q?Eugenio=20P=C3=A9rez?= , "Michael S. Tsirkin" , Sasha Levin Subject: [PATCH 6.6.y 4/4] VDUSE: avoid leaking information to userspace Date: Wed, 22 Jul 2026 14:00:52 -0400 Message-ID: <20260722180052.2184339-4-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260722180052.2184339-1-sashal@kernel.org> References: <2026072041-rectal-mammogram-740b@gregkh> <20260722180052.2184339-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Jason Wang [ Upstream commit 9c1523803445ee0348f62b77793266dd981596e0 ] The bounceing is not necessarily page aligned, so current VDUSE can leak kernel information through mapping bounce pages to userspace. Allocate bounce pages with __GFP_ZERO to avoid leaking information to userspace. Fixes: 8c773d53fb7b ("vduse: Implement an MMU-based software IOTLB") Cc: stable@vger.kernel.org Signed-off-by: Jason Wang Reviewed-by: Xie Yongji Reviewed-by: Eugenio Pérez Signed-off-by: Michael S. Tsirkin Message-ID: <20260130050750.4050-1-jasowang@redhat.com> Signed-off-by: Sasha Levin --- drivers/vdpa/vdpa_user/iova_domain.c | 2 +- drivers/vdpa/vdpa_user/vduse_dev.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/vdpa/vdpa_user/iova_domain.c b/drivers/vdpa/vdpa_user/iova_domain.c index 2b1ee3f1ba6c92..cc8d26b97187ea 100644 --- a/drivers/vdpa/vdpa_user/iova_domain.c +++ b/drivers/vdpa/vdpa_user/iova_domain.c @@ -124,7 +124,7 @@ static int vduse_domain_map_bounce_page(struct vduse_iova_domain *domain, if (!map->bounce_page) { head_map = &domain->bounce_maps[(iova & PAGE_MASK) >> BOUNCE_MAP_SHIFT]; if (!head_map->bounce_page) { - tmp_page = alloc_page(GFP_ATOMIC); + tmp_page = alloc_page(GFP_ATOMIC | __GFP_ZERO); if (!tmp_page) return -ENOMEM; if (cmpxchg(&head_map->bounce_page, NULL, tmp_page)) diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index f576e50c7ae8da..903e38bf11d435 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -832,7 +832,7 @@ static void *vduse_dev_alloc_coherent(struct device *dev, size_t size, *dma_addr = DMA_MAPPING_ERROR; - addr = alloc_pages_exact(size, flag); + addr = alloc_pages_exact(size, flag | __GFP_ZERO); if (!addr) return NULL; -- 2.53.0