[syslinux] [PATCH 2/2] core: Fix stack overflow when reloading config

[Celelibi]

2016-01-22 3:37 UTC+01:00, H. Peter Anvin <hpa at zytor.com>:
> On 01/21/16 18:33, Celelibi wrote:
>>
>> BTW, this code is due to Matt Flemming with commit 3a316db1 (later
>> modified). The commit log say this:
>>     ldlinux: Loading a config file should cause re-initialisation
>>
>>     There are a number of initialisation steps that need to be performed
>>     *every* time a config file is loaded. Reload ldlinux.c32 so that we
>>     can re-initialise the environment whenever a new config file is
>>     loaded. This involves unloading all the modules that have been loaded
>>     since ldlinux.c32. Luckily the list of loaded modules is sorted by
>>     load order, which means it's trivial to "pop" them from the front of
>>     the list.
>>
>
> Yes, it is the easy way to initialize.  Part of me wonders if we should
> keep a copy of the data section and just wipe it out.
>
> 	-hpa

I see 3 ways of handling this.
1) Have some specific code in ldlinux.c32 that handles reinitialization.
2) Have some specific cache for the COM32 modules and load them only
once for the lifetime of the whole boot loader.
3) Put a file system cache that would also benefit to other files.

I would tend to prefer the third way, but I don't know how much work
it would be or if it would integrate well in the current design.


Celelibi