On Tuesday 14 August 2012, Catalin Marinas wrote:
> +
> +void elf_set_personality(int personality)
> +{
> + switch (personality & PER_MASK) {
> + case PER_LINUX:
> + clear_thread_flag(TIF_32BIT);
> + break;
> + case PER_LINUX32:
> + set_thread_flag(TIF_32BIT);
> + break;
> + default:
> + pr_warning("Process %s tried to assume unknown personality %d\n",
> + current->comm, personality);
> + return;
> + }
> +
> + current->personality = personality;
> +}
> +EXPORT_SYMBOL(elf_set_personality);
This looks wrong: PER_LINUX/PER_LINUX32 decides over the output of the
uname system call, while TIF_32BIT decides over the instruction set
when returning to user space. You definitely should not set the personality
to the value you pass from the elf loader. Instead, just do
#define SET_PERSONALITY(ex) clear_thread_flag(TIF_32BIT);
#defined COMPAT_SET_PERSONALITY(ex) set_thread_flag(TIF_32BIT);
I also don't see a reason to export this. You'd have trouble loading
the elf interpreter module from user space without the elf interpreter.
Arnd
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