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 4673E3EA955 for ; Wed, 22 Jul 2026 16:54:39 +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=1784739280; cv=none; b=aTNET3C19lPH1PNEq6oduPIGn/wC6NT5l3Xyu6pxHTwZ8G/Oo+8EA+8uEbchEM7c9P+ruSWA7tL00kWSMhaAZ7NHHao7v+lMdPoElpQm10YtxlhgNcM+bD4Uut60/IzhIMuqQmYf8LwQ6PJt5QqhPvkK+X4zcOpwIS75yZHH5ts= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784739280; c=relaxed/simple; bh=Q89PBk4jiuGmoLzAyNUi2dvWt2LetgqGVbPEf05l9Ms=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=R3dGgqhT18bSivIhacPFmXpWahdoeM39pggvKFdck4uWsZOXdyNhV60MFranRVnobBBDLqHRk+3rUS8P4uD0dZ/AbS0luDbJnNSTAO5p07NdMpvokPcAnPKzITY3oy7kfrEOkAlj1lcVoKwjycYs0n79+vt4A51j7j+LbEkd1VA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LSBsDILI; 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="LSBsDILI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7B2381F00A3D; Wed, 22 Jul 2026 16:54:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784739279; bh=tqkyyamt+QcgFH9NFRzdMikWLyJXh7qTbPZe5zvRFNI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=LSBsDILIcyzTHciZtW7qyl3XiD74K894cui3ou9sUzh3Vq6p1xLK8475GbaZuusHV Hgtde3XUaD0PEdqFlChSc02OoUvE6aFCfxjZYiIyjELS01H7mhc8qi+ELEanYzzuQr x3XSNEWMePOg3GeN/JGvsaOICr/K8QcWpWgLORQhYlDWZWHdxAhIie62jbELV3Ykf3 dUJg0idIjtnw7hURplgZvb7nV3JvKr4xLbsh+6fBRv6ED83at/MQt2AR9J7Kcy1UV+ V7dFE3Wf9ZeZHhKit/XTyfoApsKoesaag1NyY6LjU8KftzGTot1HC711gDpQbxoVWC bYcuWLYGt38Zg== 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 6.12.y 4/4] VDUSE: avoid leaking information to userspace Date: Wed, 22 Jul 2026 12:54:33 -0400 Message-ID: <20260722165433.1853588-4-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260722165433.1853588-1-sashal@kernel.org> References: <2026072041-theft-grievous-be50@gregkh> <20260722165433.1853588-1-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 0a9f668467a8df..ec743bed361c17 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 505171a17de873..4348f4279cece6 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -864,7 +864,7 @@ 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