Messages in this thread | | | Subject | Re: [PATCH REBASE v4 05/14] arm64, mm: Make randomization selected by generic topdown mmap layout | From | Alexandre Ghiti <> | Date | Thu, 25 Jul 2019 07:48:44 +0200 |
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On 7/24/19 7:11 PM, Luis Chamberlain wrote: > On Wed, Jul 24, 2019 at 01:58:41AM -0400, Alexandre Ghiti wrote: >> diff --git a/mm/util.c b/mm/util.c >> index 0781e5575cb3..16f1e56e2996 100644 >> --- a/mm/util.c >> +++ b/mm/util.c >> @@ -321,7 +321,15 @@ unsigned long randomize_stack_top(unsigned long stack_top) >> } >> >> #ifdef CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT >> -#ifdef CONFIG_ARCH_HAS_ELF_RANDOMIZE >> +unsigned long arch_randomize_brk(struct mm_struct *mm) >> +{ >> + /* Is the current task 32bit ? */ >> + if (!IS_ENABLED(CONFIG_64BIT) || is_compat_task()) >> + return randomize_page(mm->brk, SZ_32M); >> + >> + return randomize_page(mm->brk, SZ_1G); >> +} >> + >> unsigned long arch_mmap_rnd(void) >> { >> unsigned long rnd; >> @@ -335,7 +343,6 @@ unsigned long arch_mmap_rnd(void) >> >> return rnd << PAGE_SHIFT; >> } > So arch_randomize_brk is no longer ifdef'd around > CONFIG_ARCH_HAS_ELF_RANDOMIZE either and yet the header > still has it. Is that intentional? >
Yes, CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT selects CONFIG_ARCH_HAS_ELF_RANDOMIZE, that's what's new about v4: the generic functions proposed in this series come with elf randomization.
Alex
> Luis > > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv
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