From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: UAS: fix alignment of scatter/gather segments From: Oliver Neukum Message-Id: <20190429122026.4249-1-oneukum@suse.com> Date: Mon, 29 Apr 2019 14:20:26 +0200 To: gregKH@linuxfoundation.org, linux-usb@vger.kernel.org Cc: Oliver Neukum List-ID: VGhpcyBpcyB0aGUgVUFTIHZlcnNpb24gb2YKCjc0NzY2OGRiYzA2MWIzZTYyYmMxOTgyNzY3YTNh MWY5ODE1ZmNmMGUKdXNiLXN0b3JhZ2U6IFNldCB2aXJ0X2JvdW5kYXJ5X21hc2sgdG8gYXZvaWQg U0cgb3ZlcmZsb3dzCgpXZSBhcmUgbm90IGFzIGxpa2VseSB0byBiZSB2dWxuZXJhYmxlIGFzIHN0 b3JhZ2UsIGFzIGl0IGlzIHVubGlrZWxpZXIKdGhhdCBVQVMgaXMgcnVuIG92ZXIgYSBjb250cm9s bGVyIHdpdGhvdXQgbmF0aXZlIHN1cHBvcnQgZm9yIFNHLApidXQgdGhlIGlzc3VlIGV4aXN0cy4K ClNpZ25lZC1vZmYtYnk6IE9saXZlciBOZXVrdW0gPG9uZXVrdW1Ac3VzZS5jb20+Ci0tLQogZHJp dmVycy91c2Ivc3RvcmFnZS91YXMuYyB8IDI2ICsrKysrKysrKysrKy0tLS0tLS0tLS0tLS0tCiAx IGZpbGUgY2hhbmdlZCwgMTIgaW5zZXJ0aW9ucygrKSwgMTQgZGVsZXRpb25zKC0pCgpkaWZmIC0t Z2l0IGEvZHJpdmVycy91c2Ivc3RvcmFnZS91YXMuYyBiL2RyaXZlcnMvdXNiL3N0b3JhZ2UvdWFz LmMKaW5kZXggNmQ3MWI4ZmZmOWRmLi5lYzljMWM3YmIxNTYgMTAwNjQ0Ci0tLSBhL2RyaXZlcnMv dXNiL3N0b3JhZ2UvdWFzLmMKKysrIGIvZHJpdmVycy91c2Ivc3RvcmFnZS91YXMuYwpAQCAtNzg5 LDI0ICs3ODksMjIgQEAgc3RhdGljIGludCB1YXNfc2xhdmVfYWxsb2Moc3RydWN0IHNjc2lfZGV2 aWNlICpzZGV2KQogewogCXN0cnVjdCB1YXNfZGV2X2luZm8gKmRldmluZm8gPQogCQkoc3RydWN0 IHVhc19kZXZfaW5mbyAqKXNkZXYtPmhvc3QtPmhvc3RkYXRhOworCWludCBtYXhwOwogCiAJc2Rl di0+aG9zdGRhdGEgPSBkZXZpbmZvOwogCiAJLyoKLQkgKiBVU0IgaGFzIHVudXN1YWwgRE1BLWFs aWdubWVudCByZXF1aXJlbWVudHM6IEFsdGhvdWdoIHRoZQotCSAqIHN0YXJ0aW5nIGFkZHJlc3Mg b2YgZWFjaCBzY2F0dGVyLWdhdGhlciBlbGVtZW50IGRvZXNuJ3QgbWF0dGVyLAotCSAqIHRoZSBs ZW5ndGggb2YgZWFjaCBlbGVtZW50IGV4Y2VwdCB0aGUgbGFzdCBtdXN0IGJlIGRpdmlzaWJsZQot CSAqIGJ5IHRoZSBCdWxrIG1heHBhY2tldCB2YWx1ZS4gIFRoZXJlJ3MgY3VycmVudGx5IG5vIHdh eSB0bwotCSAqIGV4cHJlc3MgdGhpcyBieSBibG9jay1sYXllciBjb25zdHJhaW50cywgc28gd2Un bGwgY29wIG91dAotCSAqIGFuZCBzaW1wbHkgcmVxdWlyZSBhZGRyZXNzZXMgdG8gYmUgYWxpZ25l ZCBhdCA1MTItYnl0ZQotCSAqIGJvdW5kYXJpZXMuICBUaGlzIGlzIG9rYXkgc2luY2UgbW9zdCBi bG9jayBJL08gaW52b2x2ZXMKLQkgKiBoYXJkd2FyZSBzZWN0b3JzIHRoYXQgYXJlIG11bHRpcGxl cyBvZiA1MTIgYnl0ZXMgaW4gbGVuZ3RoLAotCSAqIGFuZCBzaW5jZSBob3N0IGNvbnRyb2xsZXJz IHVwIHRocm91Z2ggVVNCIDIuMCBoYXZlIG1heHBhY2tldAotCSAqIHZhbHVlcyBubyBsYXJnZXIg dGhhbiA1MTIuCi0JICoKLQkgKiBCdXQgaXQgZG9lc24ndCBzdWZmaWNlIGZvciBXaXJlbGVzcyBV U0IsIHdoZXJlIEJ1bGsgbWF4cGFja2V0Ci0JICogdmFsdWVzIGNhbiBiZSBhcyBsYXJnZSBhcyAy MDQ4LiAgVG8gbWFrZSB0aGF0IHdvcmsgcHJvcGVybHkKLQkgKiB3aWxsIHJlcXVpcmUgY2hhbmdl cyB0byB0aGUgYmxvY2sgbGF5ZXIuCisJICogVVNCIGhhcyB1bnVzdWFsIHNjYXR0ZXItZ2F0aGVy IHJlcXVpcmVtZW50czogdGhlIGxlbmd0aCBvZiBlYWNoCisJICogc2NhdHRlcmxpc3QgZWxlbWVu dCBleGNlcHQgdGhlIGxhc3QgbXVzdCBiZSBkaXZpc2libGUgYnkgdGhlCisJICogQnVsayBtYXhw YWNrZXQgdmFsdWUuICBGb3J0dW5hdGVseSB0aGlzIHZhbHVlIGlzIGFsd2F5cyBhCisJICogcG93 ZXIgb2YgMi4gIEluZm9ybSB0aGUgYmxvY2sgbGF5ZXIgYWJvdXQgdGhpcyByZXF1aXJlbWVudC4K KwkgKi8KKworCW1heHAgPSB1c2JfbWF4cGFja2V0KGRldmluZm8tPnVkZXYsIGRldmluZm8tPmRh dGFfaW5fcGlwZSwgMCk7CisJYmxrX3F1ZXVlX3ZpcnRfYm91bmRhcnkoc2Rldi0+cmVxdWVzdF9x dWV1ZSwgbWF4cCAtIDEpOworCisJLyoKKwkgKiBUaGlzIG9uZSBpcyBmb3IgdGhlIGNvbnRyb2xs ZXJzLiBXZSBhc3N1bWUgNTEyIGlzIGFsd2F5cyBnb29kLgogCSAqLwogCWJsa19xdWV1ZV91cGRh dGVfZG1hX2FsaWdubWVudChzZGV2LT5yZXF1ZXN0X3F1ZXVlLCAoNTEyIC0gMSkpOwogCg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C6A01C43219 for ; Mon, 29 Apr 2019 12:20:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 923FC20578 for ; Mon, 29 Apr 2019 12:20:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728003AbfD2MUx (ORCPT ); Mon, 29 Apr 2019 08:20:53 -0400 Received: from mx2.suse.de ([195.135.220.15]:54854 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727956AbfD2MUw (ORCPT ); Mon, 29 Apr 2019 08:20:52 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 03BB0AE1D; Mon, 29 Apr 2019 12:20:50 +0000 (UTC) From: Oliver Neukum To: gregKH@linuxfoundation.org, linux-usb@vger.kernel.org Cc: Oliver Neukum Subject: [PATCH] UAS: fix alignment of scatter/gather segments Date: Mon, 29 Apr 2019 14:20:26 +0200 Message-Id: <20190429122026.4249-1-oneukum@suse.com> X-Mailer: git-send-email 2.16.4 Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Message-ID: <20190429122026.6ms-KFpgxuWcobiJD0Iaooa16ni6T0N4nZI1oxA45DI@z> This is the UAS version of 747668dbc061b3e62bc1982767a3a1f9815fcf0e usb-storage: Set virt_boundary_mask to avoid SG overflows We are not as likely to be vulnerable as storage, as it is unlikelier that UAS is run over a controller without native support for SG, but the issue exists. Signed-off-by: Oliver Neukum --- drivers/usb/storage/uas.c | 26 ++++++++++++-------------- 1 file changed, 12 insertions(+), 14 deletions(-) diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c index 6d71b8fff9df..ec9c1c7bb156 100644 --- a/drivers/usb/storage/uas.c +++ b/drivers/usb/storage/uas.c @@ -789,24 +789,22 @@ static int uas_slave_alloc(struct scsi_device *sdev) { struct uas_dev_info *devinfo = (struct uas_dev_info *)sdev->host->hostdata; + int maxp; sdev->hostdata = devinfo; /* - * USB has unusual DMA-alignment requirements: Although the - * starting address of each scatter-gather element doesn't matter, - * the length of each element except the last must be divisible - * by the Bulk maxpacket value. There's currently no way to - * express this by block-layer constraints, so we'll cop out - * and simply require addresses to be aligned at 512-byte - * boundaries. This is okay since most block I/O involves - * hardware sectors that are multiples of 512 bytes in length, - * and since host controllers up through USB 2.0 have maxpacket - * values no larger than 512. - * - * But it doesn't suffice for Wireless USB, where Bulk maxpacket - * values can be as large as 2048. To make that work properly - * will require changes to the block layer. + * USB has unusual scatter-gather requirements: the length of each + * scatterlist element except the last must be divisible by the + * Bulk maxpacket value. Fortunately this value is always a + * power of 2. Inform the block layer about this requirement. + */ + + maxp = usb_maxpacket(devinfo->udev, devinfo->data_in_pipe, 0); + blk_queue_virt_boundary(sdev->request_queue, maxp - 1); + + /* + * This one is for the controllers. We assume 512 is always good. */ blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1)); -- 2.16.4