netdev - RE: [EXT] [PATCH net] net: mvneta: fix the Rx desc buffer DMA unmapping

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 20 Sep 2018 10:14:56 +0000
From:   Yelena Krivosheev <yelena@...vell.com>
To:     Antoine Tenart <antoine.tenart@...tlin.com>,
        "davem@...emloft.net" <davem@...emloft.net>
CC:     "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "thomas.petazzoni@...tlin.com" <thomas.petazzoni@...tlin.com>,
        "maxime.chevallier@...tlin.com" <maxime.chevallier@...tlin.com>,
        "gregory.clement@...tlin.com" <gregory.clement@...tlin.com>,
        "miquel.raynal@...tlin.com" <miquel.raynal@...tlin.com>,
        Nadav Haklai <nadavh@...vell.com>,
        Stefan Chulski <stefanc@...vell.com>,
        Yan Markman <ymarkman@...vell.com>,
        "mw@...ihalf.com" <mw@...ihalf.com>
Subject: RE: [EXT] [PATCH net] net: mvneta: fix the Rx desc buffer DMA
 unmapping

Hi Antoine.

Good point.
Please, check and fix all cases of dma_unmap_single() usage.
See mvneta_rxq_drop_pkts()
...
		if (!data || !(rx_desc->buf_phys_addr))
			continue;
		dma_unmap_single(pp->dev->dev.parent, rx_desc->buf_phys_addr,
				 MVNETA_RX_BUF_SIZE(pp->pkt_size), DMA_FROM_DEVICE);
		__free_page(data);
...

Thanks.
Yelena


-----Original Message-----
From: Antoine Tenart [mailto:antoine.tenart@...tlin.com] 
Sent: Wednesday, September 19, 2018 4:29 PM
To: davem@...emloft.net; Yelena Krivosheev <yelena@...vell.com>
Cc: Antoine Tenart <antoine.tenart@...tlin.com>; netdev@...r.kernel.org; linux-kernel@...r.kernel.org; thomas.petazzoni@...tlin.com; maxime.chevallier@...tlin.com; gregory.clement@...tlin.com; miquel.raynal@...tlin.com; Nadav Haklai <nadavh@...vell.com>; Stefan Chulski <stefanc@...vell.com>; Yan Markman <ymarkman@...vell.com>; mw@...ihalf.com
Subject: [EXT] [PATCH net] net: mvneta: fix the Rx desc buffer DMA unmapping

External Email

----------------------------------------------------------------------
With CONFIG_DMA_API_DEBUG enabled we now get a warning when using the mvneta driver:

  mvneta d0030000.ethernet: DMA-API: device driver frees DMA memory with
  wrong function [device address=0x000000001165b000] [size=4096 bytes]
  [mapped as page] [unmapped as single]

This is because when using the s/w buffer management, the Rx descriptor buffer is mapped with dma_map_page but unmapped with dma_unmap_single.
This patch fixes this by using the right unmapping function.

Fixes: 562e2f467e71 ("net: mvneta: Improve the buffer allocation method for SWBM")
Signed-off-by: Antoine Tenart <antoine.tenart@...tlin.com>
---
 drivers/net/ethernet/marvell/mvneta.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index bc80a678abc3..2db9708f2e24 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -2008,8 +2008,8 @@ static int mvneta_rx_swbm(struct napi_struct *napi,
 				skb_add_rx_frag(rxq->skb, frag_num, page,
 						frag_offset, frag_size,
 						PAGE_SIZE);
-				dma_unmap_single(dev->dev.parent, phys_addr,
-						 PAGE_SIZE, DMA_FROM_DEVICE);
+				dma_unmap_page(dev->dev.parent, phys_addr,
+					       PAGE_SIZE, DMA_FROM_DEVICE);
 				rxq->left_size -= frag_size;
 			}
 		} else {
--
2.17.1