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Subject: Re: [bug reportish] UBI_MAX_ERASECOUNTER not used consistently
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Dan Carpenter <dan.carpenter@oracle.com>
Date: Thu, 11 Oct 2012 17:33:05 +0300
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On Fri, 2012-10-05 at 09:57 +0300, Dan Carpenter wrote:
> Hi Artem,
>=20
> I normally audit for underflows and I had a question about this code.
>=20
> mtd/ubi/attach.c
>    665  static int early_erase_peb(struct ubi_device *ubi,
>    666                             const struct ubi_attach_info *ai, int =
pnum, int ec)
>    667  {
>    668          int err;
>    669          struct ubi_ec_hdr *ec_hdr;
>    670 =20
>    671          if ((long long)ec >=3D UBI_MAX_ERASECOUNTER) {
>=20
> Casting to long long doesn't serve any purpose.  We normally say that
> "> UBI_MAX_ERASECOUNTER" is invalid but "=3D=3D UBI_MAX_ERASECOUNTER" is =
Ok.
> The "ec" variable is signed and negative values are missed on this
> check.

Yes, the cast is bogus. I can fix it by removing the cast, but would
like to give you a chance to send the patch so that you get the credit
being the author in the git history. Let me know what you prefer.

Thanks!

--=20
Best Regards,
Artem Bityutskiy

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