> Subject: [PATCH] drivers core: Free dma_range_map when driver probe failed
>
> There will be memory leak if driver probe failed. Trace as below:
> backtrace:
> [<000000002415258f>] kmemleak_alloc+0x3c/0x50
> [<00000000f447ebe4>] __kmalloc+0x208/0x530
> [<0000000048bc7b3a>] of_dma_get_range+0xe4/0x1b0
> [<0000000041e39065>] of_dma_configure_id+0x58/0x27c
> [<000000006356866a>] platform_dma_configure+0x2c/0x40
> ......
> [<000000000afcf9b5>] ret_from_fork+0x10/0x3c
>
> This issue is introduced by commit e0d072782c73("dma-mapping:
> introduce DMA range map, supplanting dma_pfn_offset "). It doesn't
> free dma_range_map when driver probe failed and cause above
> memory leak. So, add code to free it in error path.
>
> Fixes: e0d072782c73("dma-mapping: introduce DMA range map, supplanting
> dma_pfn_offset ")
> Cc: sta...@vger.kernel.org
> Signed-off-by: Meng Li <meng...@windriver.com>
> ---
> drivers/base/dd.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/base/dd.c b/drivers/base/dd.c
> index 148e81969e04..8e4871aa34bc 100644
> --- a/drivers/base/dd.c
> +++ b/drivers/base/dd.c
> @@ -612,6 +612,7 @@ static int really_probe(struct device *dev, struct
> device_driver *drv)
> else if (drv->remove)
> drv->remove(dev);
> probe_failed:
> + kfree(dev->dma_range_map);
> if (dev->bus)
> blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
> BUS_NOTIFY_DRIVER_NOT_BOUND,
> dev);
> --
> 2.17.1
>
> --
Hi Meng,
Sorry for the delay -- I was on vacation. I agree with you -- thanks.
However, note that in function device_release() in
drivers/base/core.c there is this line:
kfree(dev->dma_range_map);
Won't this also be called if all of the appropriate drivers' probes
fail for this device, effecting a double kfree? Perhaps your patch
could also set "dev->dma_range_map" to NULL after calling kfree()?
Thanks much,
Jim Quinlan
Broadcom STB
