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From: Nam Cao <namcao@linutronix.de>
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To: Anshika Jain <anshikajain196872@gmail.com>, Andy Shevchenko
 <andy@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, sashiko-bot@kernel.org,
 dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org,
 linux-staging@lists.linux.dev, Anshika Jain <anshikajain196872@gmail.com>
Subject: Re: [PATCH] staging: fbtft: fix len<=0 buffer overflow in
 define_fbtft_write_reg()
In-Reply-To: <20260902045026.7442-1-anshikajain196872@gmail.com>
References: <20260902045026.7442-1-anshikajain196872@gmail.com>
Date: Wed, 02 Sep 2026 14:25:46 +0200
Message-ID: <87wlt3vnzp.fsf@yellow.woof>
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Anshika Jain <anshikajain196872@gmail.com> writes:
> This is a latent bug: nothing in the current code prevents
> two adjacent negative values in an init_sequence from producing len=0,

Can you elaborate what you mean by "two adjacent negative values in an
init_sequence from producing len=0"? How is it possible that negative
values in the init sequence causing len to be zero?

> and there is no guarantee future or out-of-tree panel definitions
> won't do so.

Basic testing of future drivers would prevent such bug. It is not on any
rarely-executed code path.

Nam