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From: Li Tuo <islituo@gmail.com>
To: thomas@winischhofer.net
Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org,
	linux-kernel@vger.kernel.org, baijiaju1990@gmail.com
Subject: [BUG] video: fbdev: sis: possible uninitialized-variable access in SiS_SetCRT2FIFO_300()
Date: Sat, 31 Jul 2021 14:28:39 +0800	[thread overview]
Message-ID: <e0f988f3-f010-6299-d000-5c035e5f2e2e@gmail.com> (raw)

Hello,

Our static analysis tool finds a possible uninitialized-variable access 
in the sis driver in Linux 5.14.0-rc3:

At the beginning of the function SiS_SetCRT2FIFO_300(), the variable 
modeidindex is not initialized.
If the following conditions are false, it remains uninitialized.
5346:    if(!SiS_Pr->CRT1UsesCustomMode)
5438:    if(!SiS_Pr->UseCustomMode)

But it is accessed at:
5466:    colorth = SiS_GetColorDepth(SiS_Pr,CRT2ModeNo,modeidindex) >> 1;

I am not quite sure whether this possible uninitialized-variable access 
is real and how to fix it if it is real.
Any feedback would be appreciated, thanks!

Reported-by: TOTE Robot <oslab@tsinghua.edu.cn>

Best wishes,
Tuo Li

                 reply	other threads:[~2021-07-31  6:28 UTC|newest]

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