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SubjectQuestion about binfmt_elf.c
Date
Could somebody please update this comment to explain why fiddling with 
strangely protected bss is _not_ an easy way to leak arbitrary amounts of
uninitalized kernel memory (with whatever previous contents they have) to
userspace?

nbyte = ELF_PAGEOFFSET(elf_bss);
if (nbyte) {
nbyte = ELF_MIN_ALIGN - nbyte;
if (nbyte > elf_brk - elf_bss)
nbyte = elf_brk - elf_bss;
if (clear_user((void __user *)elf_bss +
load_bias, nbyte)) {
/*
* This bss-zeroing can fail if the ELF
* file specifies odd protections. So
* we don't check the return value
*/
}
}
Just curious. Reading through the code and trying to understand it...

Rob
--
GPLv3: as worthy a successor as The Phantom Meanace, as timely as Duke Nukem
Forever, and as welcome as New Coke.


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