Re: Patch(2.5.45): Eliminate unchecked kfree(disk->random)

[Adam J. Richter]

Al Viro wrote:
>On Mon, 4 Nov 2002, Adam J. Richter wrote:

>> 	alloc_disk in linux-2.5.45/drivers/block/genhd.c calls
>> rand_initialize_disk, which can set disk->random to NULL on kmalloc
>> failure.  disk_release does a kfree(disk->random) without checking.

>kfree(NULL) is guaranteed to be OK and is a very common idiom.  Talk
>to Linus about that - it's a religious issue and FWIW I'm on the same
>side ("free(NULL) should be allowed").  IIRC, Linus had claimed quite
>a few times that change of kfree() that would break kfree(NULL) would
>be considered as a bug.

	Oops, sorry for not checking that possibility before posting.

	I'd still like to see this patch integrated as a clean-up (it
does delete a few lines and should shrink vmlinux by a few bytes), but
it can certainly wait until post-crunch.

Adam J. Richter     __     ______________   575 Oroville Road
[e-mail]     \ /                  Milpitas, California 95035
[phone]         | g g d r a s i l   United States of America
                         "Free Software For The Rest Of Us."