Re: [PATCH v1] [ARM] pata_pxa: Fix null-ptr-deref in pxa_ata_probe()

[Damien Le Moal <dlemoal@kernel.org>]

On 4/4/25 12:58 PM, Damien Le Moal wrote:
> On 4/3/25 12:45 PM, Henry Martin wrote:

The patch title should be:

ata: pata_pxa: Fix potential NULL pointer dereference in pxa_ata_probe()

>> devm_ioremap() returns NULL on error. Currently, pxa_ata_probe() does
>> not check for this case, which results in a NULL pointer dereference.
> 
> , which can result in...
> 
>>
>> Add NULL check after devm_ioremap() to prevent this issue.
>>
>> Fixes: 2dc6c6f15da9 ("[ARM] pata_pxa: DMA-capable PATA driver")
>> Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
>> ---
>>  drivers/ata/pata_pxa.c | 7 ++++++-
>>  1 file changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/ata/pata_pxa.c b/drivers/ata/pata_pxa.c
>> index 434f380114af..cc76290a3b1a 100644
>> --- a/drivers/ata/pata_pxa.c
>> +++ b/drivers/ata/pata_pxa.c
>> @@ -223,11 +223,16 @@ static int pxa_ata_probe(struct platform_device *pdev)
>>  
>>  	ap->ioaddr.cmd_addr	= devm_ioremap(&pdev->dev, cmd_res->start,
>>  						resource_size(cmd_res));
>> +	if (!ap->ioaddr.cmd_addr)
>> +		return -ENOMEM;
>>  	ap->ioaddr.ctl_addr	= devm_ioremap(&pdev->dev, ctl_res->start,
>>  						resource_size(ctl_res));
>> +	if (!ap->ioaddr.ctl_addr)
>> +		return -ENOMEM;
>>  	ap->ioaddr.bmdma_addr	= devm_ioremap(&pdev->dev, dma_res->start,
>>  						resource_size(dma_res));
>> -
>> +	if (!ap->ioaddr.bmdma_addr)
>> +		return -ENOMEM;
> 
> Please keep the blank line here.
> 
>>  	/*
>>  	 * Adjust register offsets
>>  	 */
> 
> 


-- 
Damien Le Moal
Western Digital Research