On Thu, Jul 7, 2011 at 02:12, Helmut Raiger wrote:
On 07/06/2011 09:38 PM, Mike Frysinger wrote:
On Wednesday, July 06, 2011 03:15:08 Helmut Raiger wrote:
On 07/05/2011 05:44 AM, Mike Frysinger wrote:
On Monday, July 04, 2011 06:29:51 helmut.raiger@hale.at wrote:
eth_get_dev_by_name() is not safe to use for devname being NULL as it uses strcmp. This patch makes it return NULL if devname NULL is passed.
i'm not sure about this. passing NULL is wrong, and the caller should catch that shouldnt it ?
So what is your suggestion how to deal with it?
in what situation is eth_get_dev_by_name(NULL) being called ? my suggestion would be to fix that call point since it's doing something wrong.
I couldn't find a situation where this might be the case. But as Luca Ceresoli pointed out in his e-mail, somewhere up the thread, that he tested for devname being NULL in his miiphy_read and write routines, I checked eth_get_dev_by_name() and found that it is vulnerable to passing a NULL pointer, hence the fix.
those NULL checks should not be necessary either. a correctly written networking driver should only register itself with the miiphy layer when it has successfully registered itself with the eth layer. thus any of the miiphy callbacks should always come in with a name that is found via eth_get_dev_by_name().
checking for NULLs here and gracefully returning is unnecessary overhead imo as you're only catering to broken code. fix the broken drivers instead.
by your logic, why put the NULL check in eth_get_dev_by_name() ? why not handle strcmp(NULL, NULL) too ? then eth_get_dev_by_name() would automatically get "fixed" as would all other call points. -mike