[PATCH 4.14] mtd: rawnand: brcmnand: Fix ecc chunk calculation for erased page bitfips

[Greg Kroah-Hartman]

On Wed, Nov 29, 2023 at 05:29:13PM +0900, Yuta Hayama wrote:
> From: Claire Lin <claire.lin at broadcom.com>
> 
> commit 7f852cc1579297fd763789f8cd370639d0c654b6 upstream.
> 
> In brcmstb_nand_verify_erased_page(), the ECC chunk pointer calculation
> while correcting erased page bitflips is wrong, fix it.
> 
> Fixes: 02b88eea9f9c ("mtd: brcmnand: Add check for erased page bitflips")
> Signed-off-by: Claire Lin <claire.lin at broadcom.com>
> Reviewed-by: Ray Jui <ray.jui at broadcom.com>
> Signed-off-by: Kamal Dasu <kdasu.kdev at gmail.com>
> Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
> Signed-off-by: Yuta Hayama <hayama at lineo.co.jp>
> ---
> After applying e44b9a9c1357 ("mtd: nand: brcmnand: Zero bitflip is not an
> error"), the return value 0 of brcmstb_nand_verify_erased_page() is
> *correctly* interpreted as "no bit flips, no errors". However, that
> function still has the issue that it may incorrectly return 0 for a page
> that contains bitflips. Without this patch, the data buffer of the erased
> page could be passed to a upper layer (e.g. UBIFS) without bitflips being
> detected and corrected.
> 
> In active stable, 4.14.y and 4.19.y seem to have a same issue.

Both now queued up, thanks.

greg k-h