* [PATCH] Pci: host - Fix possible NULL derefrence. [not found] <CGME20170130044942epcas2p4c3e879675c189ff46c27b5f35bbc350f@epcas2p4.samsung.com> @ 2017-01-30 4:49 ` Shailendra Verma 2017-01-31 15:09 ` Bjorn Helgaas 0 siblings, 1 reply; 3+ messages in thread From: Shailendra Verma @ 2017-01-30 4:49 UTC (permalink / raw) To: Zhou Wang, Gabriele Paoloni, Bjorn Helgaas, linux-pci, linux-kernel, p.shailesh, ashish.kalra, Shailendra Verma, Shailendra Verma of_match_device could return NULL, and so can cause a NULL pointer dereference later. Signed-off-by: Shailendra Verma <shailendra.v@samsung.com> --- drivers/pci/host/pcie-hisi.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/pci/host/pcie-hisi.c b/drivers/pci/host/pcie-hisi.c index 56154c2..3256f8f 100644 --- a/drivers/pci/host/pcie-hisi.c +++ b/drivers/pci/host/pcie-hisi.c @@ -174,6 +174,10 @@ static int hisi_pcie_probe(struct platform_device *pdev) driver = dev->driver; match = of_match_device(driver->of_match_table, dev); + if (!match) { + dev_err(dev, "Error: No device match found\n"); + return -ENODEV; + } hisi_pcie->soc_ops = (struct pcie_soc_ops *) match->data; hisi_pcie->subctrl = -- 1.7.9.5 ^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] Pci: host - Fix possible NULL derefrence. 2017-01-30 4:49 ` [PATCH] Pci: host - Fix possible NULL derefrence Shailendra Verma @ 2017-01-31 15:09 ` Bjorn Helgaas 2017-01-31 18:22 ` Bjorn Helgaas 0 siblings, 1 reply; 3+ messages in thread From: Bjorn Helgaas @ 2017-01-31 15:09 UTC (permalink / raw) To: Shailendra Verma Cc: Zhou Wang, Gabriele Paoloni, Bjorn Helgaas, linux-pci, linux-kernel, p.shailesh, ashish.kalra, Shailendra Verma Hi Shailendra, On Mon, Jan 30, 2017 at 10:19:35AM +0530, Shailendra Verma wrote: > of_match_device could return NULL, and so can cause a NULL > pointer dereference later. > > Signed-off-by: Shailendra Verma <shailendra.v@samsung.com> > --- > drivers/pci/host/pcie-hisi.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/pci/host/pcie-hisi.c b/drivers/pci/host/pcie-hisi.c > index 56154c2..3256f8f 100644 > --- a/drivers/pci/host/pcie-hisi.c > +++ b/drivers/pci/host/pcie-hisi.c > @@ -174,6 +174,10 @@ static int hisi_pcie_probe(struct platform_device *pdev) > driver = dev->driver; > > match = of_match_device(driver->of_match_table, dev); > + if (!match) { > + dev_err(dev, "Error: No device match found\n"); > + return -ENODEV; > + } > hisi_pcie->soc_ops = (struct pcie_soc_ops *) match->data; > > hisi_pcie->subctrl = I like this patch and I think it's correct. I'd like an ack from Zhou and/or Gabriele, and I'd propose the following tweak, which just moves the check earlier, before we start allocating this: commit 0bd4137b946cab412d612ae155f3b268f2f0a856 Author: Shailendra Verma <shailendra.v@samsung.com> Date: Mon Jan 30 10:19:35 2017 +0530 PCI: hisi: Check of_match_device() return value of_match_device() could return NULL, and so can cause a NULL pointer dereference later. Check the result first, before we start setting up things that need to be undone if it fails. [bhelgaas: check earlier, changelog] Signed-off-by: Shailendra Verma <shailendra.v@samsung.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> diff --git a/drivers/pci/host/pcie-hisi.c b/drivers/pci/host/pcie-hisi.c index a301a7187b30..0f0521169a3c 100644 --- a/drivers/pci/host/pcie-hisi.c +++ b/drivers/pci/host/pcie-hisi.c @@ -264,6 +264,10 @@ static int hisi_pcie_probe(struct platform_device *pdev) struct device_driver *driver; int ret; + match = of_match_device(driver->of_match_table, dev); + if (!match) + return -ENODEV; + hisi_pcie = devm_kzalloc(dev, sizeof(*hisi_pcie), GFP_KERNEL); if (!hisi_pcie) return -ENOMEM; @@ -272,7 +276,6 @@ static int hisi_pcie_probe(struct platform_device *pdev) pp->dev = dev; driver = dev->driver; - match = of_match_device(driver->of_match_table, dev); hisi_pcie->soc_ops = (struct pcie_soc_ops *) match->data; hisi_pcie->subctrl = ^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] Pci: host - Fix possible NULL derefrence. 2017-01-31 15:09 ` Bjorn Helgaas @ 2017-01-31 18:22 ` Bjorn Helgaas 0 siblings, 0 replies; 3+ messages in thread From: Bjorn Helgaas @ 2017-01-31 18:22 UTC (permalink / raw) To: Shailendra Verma Cc: Zhou Wang, Gabriele Paoloni, Bjorn Helgaas, linux-pci, linux-kernel, p.shailesh, ashish.kalra, Shailendra Verma On Tue, Jan 31, 2017 at 09:09:00AM -0600, Bjorn Helgaas wrote: > Hi Shailendra, > > On Mon, Jan 30, 2017 at 10:19:35AM +0530, Shailendra Verma wrote: > > of_match_device could return NULL, and so can cause a NULL > > pointer dereference later. > > > > Signed-off-by: Shailendra Verma <shailendra.v@samsung.com> > > --- > > drivers/pci/host/pcie-hisi.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/drivers/pci/host/pcie-hisi.c b/drivers/pci/host/pcie-hisi.c > > index 56154c2..3256f8f 100644 > > --- a/drivers/pci/host/pcie-hisi.c > > +++ b/drivers/pci/host/pcie-hisi.c > > @@ -174,6 +174,10 @@ static int hisi_pcie_probe(struct platform_device *pdev) > > driver = dev->driver; > > > > match = of_match_device(driver->of_match_table, dev); > > + if (!match) { > > + dev_err(dev, "Error: No device match found\n"); > > + return -ENODEV; > > + } > > hisi_pcie->soc_ops = (struct pcie_soc_ops *) match->data; > > > > hisi_pcie->subctrl = > > I like this patch and I think it's correct. I'd like an ack from Zhou > and/or Gabriele, and I'd propose the following tweak, which just moves the > check earlier, before we start allocating this: Geert pointed out in a similar case that it's actually impossible for match to be NULL here because the only way to call hisi_pcie_probe() is to match an entry in hisi_pcie_of_match[]. So I think the following patch is even better because it removes a mention of driver->of_match_table. I can't easily build test to be sure, but I think the cast is also unnecessary. commit 806d19760e48166505818d4efafbdfbad5810989 Author: Shailendra Verma <shailendra.v@samsung.com> Date: Mon Jan 30 10:19:35 2017 +0530 PCI: hisi: Use of_device_get_match_data() to simplify probe The only way to call hisi_pcie_probe() is to match an entry in hisi_pcie_of_match[], so match cannot be NULL. Use of_device_get_match_data() to retrieve the soc_ops pointer. No functional change intended. [bhelgaas: use of_device_get_match_data(), changelog] Based-on-suggestion-from: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Shailendra Verma <shailendra.v@samsung.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> diff --git a/drivers/pci/host/pcie-hisi.c b/drivers/pci/host/pcie-hisi.c index a301a7187b30..34d10d242225 100644 --- a/drivers/pci/host/pcie-hisi.c +++ b/drivers/pci/host/pcie-hisi.c @@ -259,7 +259,6 @@ static int hisi_pcie_probe(struct platform_device *pdev) struct device *dev = &pdev->dev; struct hisi_pcie *hisi_pcie; struct pcie_port *pp; - const struct of_device_id *match; struct resource *reg; struct device_driver *driver; int ret; @@ -272,11 +271,10 @@ static int hisi_pcie_probe(struct platform_device *pdev) pp->dev = dev; driver = dev->driver; - match = of_match_device(driver->of_match_table, dev); - hisi_pcie->soc_ops = (struct pcie_soc_ops *) match->data; + hisi_pcie->soc_ops = of_device_get_match_data(dev); hisi_pcie->subctrl = - syscon_regmap_lookup_by_compatible("hisilicon,pcie-sas-subctrl"); + syscon_regmap_lookup_by_compatible("hisilicon,pcie-sas-subctrl"); if (IS_ERR(hisi_pcie->subctrl)) { dev_err(dev, "cannot get subctrl base\n"); return PTR_ERR(hisi_pcie->subctrl); ^ permalink raw reply related [flat|nested] 3+ messages in thread
end of thread, other threads:[~2017-01-31 18:22 UTC | newest] Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- [not found] <CGME20170130044942epcas2p4c3e879675c189ff46c27b5f35bbc350f@epcas2p4.samsung.com> 2017-01-30 4:49 ` [PATCH] Pci: host - Fix possible NULL derefrence Shailendra Verma 2017-01-31 15:09 ` Bjorn Helgaas 2017-01-31 18:22 ` Bjorn Helgaas
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