Re: [PATCH][RFC] invalid ELF binaries can execute - better sanity checking

[Anton Blanchard]

> I've always had little confidence in the elf loader.  The problem is
> complex, the code quality is not high and the consequences of an error are
> severe.

One thing I noticed is that we only obey execute permission on load
sections. On ppc32 the PLT is in the bss area and must be executable:

[27] .sbss             PROGBITS        100ba10c 0aa10c 000a14 00  WA 0   0  8
[28] .plt              PROGBITS        100bab20 0aab20 000834 00 WAX 0   0  4  
[29] .bss              NOBITS          100bb358 0ab354 003f90 00  WA 0   0  8

When I did per page execute for ppc64 we fell apart because the current
elf loader just creates a single region of non executable memory
regardless of what the binary asks for.

Anton
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