linux-kernel - Re: [PATCH v1 1/1] drm/mediatek: Fix wrong check of nvmem_cell

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <d8f54575-6df8-4198-a078-70debc9f8e0b@collabora.com>
Date: Thu, 26 Sep 2024 11:33:59 +0200
From: AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>
To: Liankun Yang <liankun.yang@...iatek.com>, chunkuang.hu@...nel.org,
 p.zabel@...gutronix.de, airlied@...il.com, simona@...ll.ch,
 matthias.bgg@...il.com, rex-bc.chen@...iatek.com, msp@...libre.com,
 granquet@...libre.com, dmitry.osipenko@...labora.com,
 jitao.shi@...iatek.com, mac.shen@...iatek.com, peng.liu@...iatek.com
Cc: Project_Global_Chrome_Upstream_Group@...iatek.com,
 dri-devel@...ts.freedesktop.org, linux-mediatek@...ts.infradead.org,
 linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH v1 1/1] drm/mediatek: Fix wrong check of nvmem_cell_read

Il 25/09/24 10:40, Liankun Yang ha scritto:
> If the len is 0, kernel crash will occur when performing operations.
> Add the len check conditions to prevent kernel crash.
> 

Please fix the commit title:

drm/mediatek: mtk_dp: Fix potential KP on 0 bytes nvmem cell read

> Fixes: f70ac097a2cf ("drm/mediatek: Add MT8195 Embedded DisplayPort driver")
> 

Please remove this blank line between the Fixes tag and your S-o-b.

> Signed-off-by: Liankun Yang <liankun.yang@...iatek.com>
> ---
>   drivers/gpu/drm/mediatek/mtk_dp.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c
> index d8796a904eca..0cc75ba96b98 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dp.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dp.c
> @@ -1082,7 +1082,7 @@ static void mtk_dp_get_calibration_data(struct mtk_dp *mtk_dp)
>   	buf = (u32 *)nvmem_cell_read(cell, &len);
>   	nvmem_cell_put(cell);
>   
> -	if (IS_ERR(buf) || ((len / sizeof(u32)) != 4)) {
> +	if (IS_ERR(buf) || (len == 0) || ((len / sizeof(u32)) != 4)) {

if (IS_ERR(buf) || !len || ((len / sizeof(u32)) != 4)) {

Cheers,
Angelo