Differential D21081 Diff 60337 head/sys/kern/imgact_elf.c

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head/sys/kern/imgact_elf.c

Show First 20 Lines • Show All 150 Lines • ▼ Show 20 Lines	SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, pie_enable, CTLFLAG_RWTUN,
__XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))		__XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
": enable address map randomization for PIE binaries");		": enable address map randomization for PIE binaries");

static int __elfN(aslr_honor_sbrk) = 1;		static int __elfN(aslr_honor_sbrk) = 1;
SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, honor_sbrk, CTLFLAG_RW,		SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, honor_sbrk, CTLFLAG_RW,
&__elfN(aslr_honor_sbrk), 0,		&__elfN(aslr_honor_sbrk), 0,
__XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": assume sbrk is used");		__XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": assume sbrk is used");

		static int __elfN(aslr_stack_gap) = 3;
		SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, stack_gap, CTLFLAG_RW,
		&__elfN(aslr_stack_gap), 0,
		__XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
		": maximum percentage of main stack to waste on a random gap");

static Elf_Brandinfo *elf_brand_list[MAX_BRANDS];		static Elf_Brandinfo *elf_brand_list[MAX_BRANDS];

#define aligned(a, t) (rounddown2((u_long)(a), sizeof(t)) == (u_long)(a))		#define aligned(a, t) (rounddown2((u_long)(a), sizeof(t)) == (u_long)(a))

static const char FREEBSD_ABI_VENDOR[] = "FreeBSD";		static const char FREEBSD_ABI_VENDOR[] = "FreeBSD";

Elf_Brandnote __elfN(freebsd_brandnote) = {		Elf_Brandnote __elfN(freebsd_brandnote) = {
.hdr.n_namesz = sizeof(FREEBSD_ABI_VENDOR),		.hdr.n_namesz = sizeof(FREEBSD_ABI_VENDOR),
▲ Show 20 Lines • Show All 2,547 Lines • ▼ Show 20 Lines	__elfN(untrans_prot)(vm_prot_t prot)
flags = 0;		flags = 0;
if (prot & VM_PROT_EXECUTE)		if (prot & VM_PROT_EXECUTE)
flags \|= PF_X;		flags \|= PF_X;
if (prot & VM_PROT_READ)		if (prot & VM_PROT_READ)
flags \|= PF_R;		flags \|= PF_R;
if (prot & VM_PROT_WRITE)		if (prot & VM_PROT_WRITE)
flags \|= PF_W;		flags \|= PF_W;
return (flags);		return (flags);
		}

		void
		__elfN(stackgap)(struct image_params imgp, u_long stack_base)
		{
		u_long range, rbase, gap;
		int pct;

		if ((imgp->map_flags & MAP_ASLR) == 0)
		return;
		pct = __elfN(aslr_stack_gap);
		if (pct == 0)
		return;
		if (pct > 50)
		pct = 50;
		range = imgp->eff_stack_sz * pct / 100;
		range *= pct;
		arc4rand(&rbase, sizeof(rbase), 0);
		gap = rbase % range;
		gap &= ~(sizeof(u_long) - 1);
		*stack_base -= gap;
}		}