Re: [PATCH] usb: isp1760: fix null dereference if kzalloc returns null

From: Sergei Shtylyov
Date: Sun May 31 2015 - 18:15:39 EST


Hello.

On 06/01/2015 01:00 AM, Colin King wrote:

From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

If kzalloc returns null then isp1760_ep_alloc_request performs
a null pointer deference on req.

Dereference, not "deference".
No, it doesn't. It calculates the address of the 'isp1760_request::req' instead, there's no dereference per se. I suppose this is a first member of the structure, so this function should work correctly in any case.

Check for null to avoid this.

Detected with smatch static analysis:

drivers/usb/isp1760/isp1760-udc.c:816 isp1760_ep_alloc_request()
error: potential null dereference 'req'. (kzalloc returns null)

Well, the change won't hurt anyway, makes things clearer.

Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>

WBR, Sergei

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