Re: [PATCH] PCI: iproc: fix kernel crash if dev->of_node not defined

From: Abylay Ospan
Date: Fri Jan 13 2017 - 00:59:29 EST


FYI,

here is my tree (based on linux-next):
https://github.com/aospan/linux-next-bcm4708-edgecore-ecw7220-l/commits/master

last patches adding defconfig and dts I'm using for this device. This
files are draft yet.

2017-01-12 19:22 GMT-05:00 Florian Fainelli <f.fainelli@xxxxxxxxx>:
> On 01/12/2017 04:20 PM, Abylay Ospan wrote:
>> pcie->dev->of_node not always defined (NULL) and can cause crash:
>>
>> [ 19.053195] Unable to handle kernel NULL pointer dereference at
>> virtual address 00000020
>> [<c0b0370c>] (of_n_addr_cells) from [<c06599c4>]
>> (iproc_pcie_setup+0x30c/0xce0)
>>
>> this patch adds sanity check to prevent crash.
>
> Humm, how can it not be defined based on your earlier comment that you
> are using this on NSP which is Device Tree exclusively? I would agree if
> this was seen on e.g: MIPS/BCMA (47xx).
>
>>
>> Signed-off-by: Abylay Ospan <aospan@xxxxxxxx>
>> ---
>> drivers/pci/host/pcie-iproc.c | 3 +++
>> 1 file changed, 3 insertions(+)
>>
>> diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c
>> index 3ebc025..f2836a9 100644
>> --- a/drivers/pci/host/pcie-iproc.c
>> +++ b/drivers/pci/host/pcie-iproc.c
>> @@ -952,6 +952,9 @@ static int pci_dma_range_parser_init(struct of_pci_range_parser *parser,
>> const int na = 3, ns = 2;
>> int rlen;
>>
>> + if (!node)
>> + return -ENOENT;
>> +
>> parser->node = node;
>> parser->pna = of_n_addr_cells(node);
>> parser->np = parser->pna + na + ns;
>>
>
>
> --
> Florian



--
Abylay Ospan,
NetUP Inc.
http://www.netup.tv