Re: [PATCH v2] block: register_blkdev doesn't check name againstNULL

From: vaughan
Date: Sun Sep 29 2013 - 02:52:49 EST


On 09/23/2013 10:56 PM, Jeff Moyer wrote:
> Vaughan Cao <vaughan.cao@xxxxxxxxxx> writes:
>
>> register_blkdev(0, NULL) can result kernel Oops by copying from NULL
>> in strlcpy(). Fix it by checking NULL pointer at the beginning and
>> WARN when encountered in unregister_blkdev.
> Uhh, so yeah, this is an exported function, so I could see maybe wanting
> to do the argument checking. But honestly, if your driver can't even
> get this right, is there any hope of it actually working?
>
> This seems like a pointless patch to me, but ultimately it's up to Jens.
>
> Cheers,
> Jeff
>
> p.s. the kerneldoc tells you what to put there:
> * @name: the name of the new block device as a zero terminated string
Thanks for your comment, Jeff. I have the same feeling as you, however,
shouldn't kernel do its best to provide the maximum stable working ability?
And it's test case 7 of block driver in ltp project -
http://sourceforge.net/p/ltp/git/ci/master/tree/testcases/kernel/device-drivers/block/kernel_space/test_block.c.
It seems their attitude is we should check this.

Vaughan
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