Re: [PATCH] video/logo: fix use logo after free prevention

From: Tomi Valkeinen
Date: Fri Apr 17 2015 - 06:40:46 EST


Hi,

On 04/17/2015 12:48 PM, Manfred Schlaegl wrote:
After 92b004d1aa9f367c372511ca0330f58216b25703 the logos disappeared on
Freescale i.MX53 and i.MX6 SoC's (detected on linux-3.12.37).
This happens because the fb_find_logo function is validly called
(initdata still not freed) AFTER newly introduced latecall
fb_logo_late_init.

Instead of stetting a logos_freed flag somewhere in lateinit, this patch
uses system_state==SYSTEM_BOOTING as indication for valid initdata.

The kernel init does free_initmem() call before setting the system_state to SYSTEM_RUNNING, so there's a period of time when the logos are freed, but the check in you patch does not catch it.

Tomi
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