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 3968218CBE1 for ; Thu, 23 Jul 2026 01:16:53 +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=1784769414; cv=none; b=OpNJETeBByb5xvp6kRMHjVFWEFa0kIoQetH8yA8DQrhxicOe8DnaOksZK6ch7SdsUN1AUPgFxdYCliKWcQg3Gq8kM5a6whgXhIH/B6c9KOE6l8WR73rLnpzhlNDumsrOZP05sKyDc4hMhwWViL99b105JQ1+uLCtKuvUj2jYYzE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784769414; c=relaxed/simple; bh=Yv23/DmJdLKJy7ixEb2vxMmU3zI6/cOScSXMxlmk948=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=URBWrW8rS73wHRmPXI+uHdVLJMuZNntnTs/AhHAwXx7Ewb10xC0LmhCo2GiFVSWge4qfKHxDYt6Sjo3e7d1vlyWoRpWx/uVJv02wpCWKOiOOuzztpOUfyCE0c9v+iWbEqjymwlVT8N2YuW4q7sX/mal198icwEX7NcxaO9fYh5o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DlCD9SZM; 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="DlCD9SZM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4ADD11F000E9; Thu, 23 Jul 2026 01:16:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784769412; bh=ammtBjEFsCZCQhkxWVl73/AyI4pW1wFhaqtm9YDzVfY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=DlCD9SZMiDjius5YdT4e1lBTS4n2e4FhFbaUN869rKppRXhGjHhnDXL2/2ewpp2zi PGUn3kl8HS0IBw11afThC2ZlYG5xPjkXv6UuDAPa8og5kHTloLSvooIrDguaIT0l9w aC9OYcyYb/R2mTJGCxO5ZeTnm++f6jUYpenP/+uPwggoVj4r+Lkifpo+z9sPV9OeEn jsYJelzxsu3UUoyEDA2ayCEWvaNWlydG1tiHwUbflPbVR8YEPN9vxhvpOy2vmri9D1 iJ7sqaTwhIgugmhyJRQSqB1HuIbpvouZRH7z+uO0OvyqismdeVEsWZHvwSfNkTJw6b SGSowid0vx9NQ== 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 5.15.y 4/4] VDUSE: avoid leaking information to userspace Date: Wed, 22 Jul 2026 21:16:48 -0400 Message-ID: <20260723011648.2779203-4-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260723011648.2779203-1-sashal@kernel.org> References: <2026072042-challenge-grimacing-a682@gregkh> <20260723011648.2779203-1-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 26f3fb5e0b0677..783319f1607619 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 8f05d1bfdb1076..ce84b0fb8428d3 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -776,7 +776,7 @@ 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