Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933780AbcDSROu (ORCPT ); Tue, 19 Apr 2016 13:14:50 -0400 Received: from mail-qg0-f66.google.com ([209.85.192.66]:36497 "EHLO mail-qg0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932931AbcDSROr (ORCPT ); Tue, 19 Apr 2016 13:14:47 -0400 Date: Tue, 19 Apr 2016 13:14:43 -0400 From: "David Rivshin (Allworx)" To: Grygorii Strashko , "David S. Miller" Cc: Andrew Goodbody , , , , , Subject: Re: [PATCH v2 1/1] drivers: net: cpsw: Prevent NUll pointer dereference with two PHYs Message-ID: <20160419131443.7a3b3ef7.drivshin.allworx@gmail.com> In-Reply-To: <57165269.40207@ti.com> References: <1461074186-25535-1-git-send-email-andrew.goodbody@cambrionix.com> <1461074186-25535-2-git-send-email-andrew.goodbody@cambrionix.com> <57164383.6080103@ti.com> <20160419110140.75e35c3c.drivshin.allworx@gmail.com> <57165269.40207@ti.com> Organization: Allworx X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8090 Lines: 189 On Tue, 19 Apr 2016 18:44:41 +0300 Grygorii Strashko wrote: > On 04/19/2016 06:01 PM, David Rivshin (Allworx) wrote: > > On Tue, 19 Apr 2016 17:41:07 +0300 > > Grygorii Strashko wrote: > > > >> Hi, > >> > >> On 04/19/2016 04:56 PM, Andrew Goodbody wrote: > >>> Adding a 2nd PHY to cpsw results in a NULL pointer dereference > >>> as below. Fix by maintaining a reference to each PHY node in slave > >>> struct instead of a single reference in the priv struct which was > >>> overwritten by the 2nd PHY. > >> > >> David, Is it possible to drop prev version of this patch from linux-next > >> - it breaks boot on many TI boards with -next. > >> > >> > >>> > >>> [ 17.870933] Unable to handle kernel NULL pointer dereference at virtual address 00000180 > >>> [ 17.879557] pgd = dc8bc000 > >>> [ 17.882514] [00000180] *pgd=9c882831, *pte=00000000, *ppte=00000000 > >>> [ 17.889213] Internal error: Oops: 17 [#1] ARM > >>> [ 17.893838] Modules linked in: > >>> [ 17.897102] CPU: 0 PID: 1657 Comm: connmand Not tainted 4.5.0-ge463dfb-dirty #11 > >>> [ 17.904947] Hardware name: Cambrionix whippet > >>> [ 17.909576] task: dc859240 ti: dc968000 task.ti: dc968000 > >>> [ 17.915339] PC is at phy_attached_print+0x18/0x8c > >>> [ 17.920339] LR is at phy_attached_info+0x14/0x18 > >>> [ 17.925247] pc : [] lr : [] psr: 600f0113 > >>> [ 17.925247] sp : dc969cf8 ip : dc969d28 fp : dc969d18 > >>> [ 17.937425] r10: dda7a400 r9 : 00000000 r8 : 00000000 > >>> [ 17.942971] r7 : 00000001 r6 : ddb00480 r5 : ddb8cb34 r4 : 00000000 > >>> [ 17.949898] r3 : c0954cc0 r2 : c09562b0 r1 : 00000000 r0 : 00000000 > >>> [ 17.956829] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none > >>> [ 17.964401] Control: 10c5387d Table: 9c8bc019 DAC: 00000051 > >>> [ 17.970500] Process connmand (pid: 1657, stack limit = 0xdc968210) > >>> [ 17.977059] Stack: (0xdc969cf8 to 0xdc96a000) > >> > >> [...] > >> > >>> [ 18.323956] [] (inet_ioctl) from [] (sock_ioctl+0x15c/0x2d8) > >>> [ 18.331829] [] (sock_ioctl) from [] (do_vfs_ioctl+0x98/0x8d0) > >>> [ 18.339765] r7:00008914 r6:dc8ab4c0 r5:dd257ae0 r4:beaeda20 > >>> [ 18.345822] [] (do_vfs_ioctl) from [] (SyS_ioctl+0x74/0x84) > >>> [ 18.353573] r10:00000000 r9:00000011 r8:beaeda20 r7:00008914 r6:dc8ab4c0 r5:dc8ab4c0 > >>> [ 18.361924] r4:00000000 > >>> [ 18.364653] [] (SyS_ioctl) from [] (ret_fast_syscall+0x0/0x3c) > >>> [ 18.372682] r9:dc968000 r8:c00165e8 r7:00000036 r6:00000002 r5:00000011 r4:00000000 > >>> [ 18.380960] Code: e92dd810 e24cb010 e24dd010 e59b4004 (e5902180) > >>> [ 18.387580] ---[ end trace c80529466223f3f3 ]--- > >> > >> ^ Could you make it shorter and drop timestamps, pls? > >> > >>> > >>> Signed-off-by: Andrew Goodbody > >>> --- > >>> > >>> v2 - Move allocation of memory for priv->slaves to inside cpsw_probe_dt so it > >>> has data->slaves initialised first which is needed to calculate size > >>> > >>> drivers/net/ethernet/ti/cpsw.c | 30 +++++++++++++++--------------- > >>> 1 file changed, 15 insertions(+), 15 deletions(-) > >>> > >>> diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c > >>> index 42fdfd4..e62909c 100644 > >>> --- a/drivers/net/ethernet/ti/cpsw.c > >>> +++ b/drivers/net/ethernet/ti/cpsw.c > >>> @@ -349,6 +349,7 @@ struct cpsw_slave { > >>> struct cpsw_slave_data *data; > >>> struct phy_device *phy; > >>> struct net_device *ndev; > >>> + struct device_node *phy_node; > >>> u32 port_vlan; > >>> u32 open_stat; > >>> }; > >>> @@ -367,7 +368,6 @@ struct cpsw_priv { > >>> spinlock_t lock; > >>> struct platform_device *pdev; > >>> struct net_device *ndev; > >>> - struct device_node *phy_node; > >>> struct napi_struct napi_rx; > >>> struct napi_struct napi_tx; > >>> struct device *dev; > >>> @@ -1148,8 +1148,8 @@ static void cpsw_slave_open(struct cpsw_slave *slave, struct cpsw_priv *priv) > >>> cpsw_ale_add_mcast(priv->ale, priv->ndev->broadcast, > >>> 1 << slave_port, 0, 0, ALE_MCAST_FWD_2); > >>> > >>> - if (priv->phy_node) > >>> - slave->phy = of_phy_connect(priv->ndev, priv->phy_node, > >>> + if (slave->phy_node) > >>> + slave->phy = of_phy_connect(priv->ndev, slave->phy_node, > >>> &cpsw_adjust_link, 0, slave->data->phy_if); > >>> else > >>> slave->phy = phy_connect(priv->ndev, slave->data->phy_id, > >>> @@ -1946,7 +1946,7 @@ static int cpsw_probe_dt(struct cpsw_priv *priv, > >>> struct device_node *node = pdev->dev.of_node; > >>> struct device_node *slave_node; > >>> struct cpsw_platform_data *data = &priv->data; > >>> - int i = 0, ret; > >>> + int i, ret; > >>> u32 prop; > >>> > >>> if (!node) > >>> @@ -1958,6 +1958,14 @@ static int cpsw_probe_dt(struct cpsw_priv *priv, > >>> } > >>> data->slaves = prop; > >>> > >>> + priv->slaves = devm_kzalloc(&pdev->dev, > >>> + sizeof(struct cpsw_slave) * data->slaves, > >>> + GFP_KERNEL); > >>> + if (!priv->slaves) > >>> + return -ENOMEM; > >>> + for (i = 0; i < data->slaves; i++) > >>> + priv->slaves[i].slave_num = i; > >>> + > >>> if (of_property_read_u32(node, "active_slave", &prop)) { > >>> dev_err(&pdev->dev, "Missing active_slave property in the DT.\n"); > >>> return -EINVAL; > >>> @@ -2023,6 +2031,7 @@ static int cpsw_probe_dt(struct cpsw_priv *priv, > >>> if (ret) > >>> dev_warn(&pdev->dev, "Doesn't have any child node\n"); > >>> > >>> + i = 0; > >>> for_each_child_of_node(node, slave_node) { > >>> struct cpsw_slave_data *slave_data = data->slave_data + i; > >>> const void *mac_addr = NULL; > >>> @@ -2033,7 +2042,8 @@ static int cpsw_probe_dt(struct cpsw_priv *priv, > >>> if (strcmp(slave_node->name, "slave")) > >>> continue; > >>> > >>> - priv->phy_node = of_parse_phandle(slave_node, "phy-handle", 0); > >>> + priv->slaves[i].phy_node = > >>> + of_parse_phandle(slave_node, "phy-handle", 0); > >> > >> i++? > >> > >> Ideally, the simplest way is to save phy_node in slave_data, but ... > >> (see comment below). > > > > FYI, I have a patch [1] that does exactly that in my queue. Sorry > > I've been busy and haven't had a chance to rebase/retest/resubmit > > since Nicolas gave his Tested-By (and I missed Andrew's original > > patch). I can probably steal some time to resurrect that quickly > > if it's preferred, just let me know. > > > > [1] http://www.spinics.net/lists/netdev/msg357772.html > > Ah Ok. There are no user of cpsw_platform_data outside of net/ethernet/ti/, > so yes, looks like your patch 1 does exactly what's needed. Given that the v1 of Andrew's patch is already in Dave's net tree, and would obviously have many conflicts with mine, how should I proceed? Since you already requested Dave revert that patch, should I just wait for that to happen and then resubmit my series? Dave, Does that sound good to you? > > > > >> > >> > >>> parp = of_get_property(slave_node, "phy_id", &lenp); > >>> if (of_phy_is_fixed_link(slave_node)) { > >>> struct device_node *phy_node; > >>> @@ -2292,16 +2302,6 @@ static int cpsw_probe(struct platform_device *pdev) > >>> > >>> memcpy(ndev->dev_addr, priv->mac_addr, ETH_ALEN); > >>> > >>> - priv->slaves = devm_kzalloc(&pdev->dev, > >>> - sizeof(struct cpsw_slave) * data->slaves, > >>> - GFP_KERNEL); > >>> - if (!priv->slaves) { > >>> - ret = -ENOMEM; > >>> - goto clean_runtime_disable_ret; > >>> - } > >> I don't think you can move this out from here - it will break legacy boot :( > >> > >> > >>> - for (i = 0; i < data->slaves; i++) > >>> - priv->slaves[i].slave_num = i; > >> > >> Personally, I see only one safe way to do it without big rework - > >> do second pass of DT parsing here to fill phy_node field. > >> > > >