Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 465f1ea5 authored by Jon Medhurst's avatar Jon Medhurst Committed by Tixy
Browse files

ARM: kprobes: Reject probing of unprivileged load and store instructions 



These occur extremely rarely in the kernel and writing test cases for
them is difficult.

Signed-off-by: default avatarJon Medhurst <tixy@yxit.co.uk>
Acked-by: default avatarNicolas Pitre <nicolas.pitre@linaro.org>
parent 711bf106

arch/arm/kernel/kprobes-arm.c

+13 −0
Original line number Diff line number Diff line
@@ -1262,6 +1262,13 @@ static const union decode_item arm_cccc_0001_____1001_table[] = { 
static const union decode_item arm_cccc_000x_____1xx1_table[] = {

	/* Extra load/store instructions				*/



	/* STRHT		cccc 0000 xx10 xxxx xxxx xxxx 1011 xxxx */

	/* ???			cccc 0000 xx10 xxxx xxxx xxxx 11x1 xxxx */

	/* LDRHT		cccc 0000 xx11 xxxx xxxx xxxx 1011 xxxx */

	/* LDRSBT		cccc 0000 xx11 xxxx xxxx xxxx 1101 xxxx */

	/* LDRSHT		cccc 0000 xx11 xxxx xxxx xxxx 1111 xxxx */

	DECODE_REJECT	(0x0f200090, 0x00200090),



	/* LDRD/STRD lr,pc,{...	cccc 000x x0x0 xxxx 111x xxxx 1101 xxxx */

	DECODE_REJECT	(0x0e10e0d0, 0x0000e0d0),
@@ -1564,6 +1571,12 @@ static const union decode_item arm_cccc_01xx_table[] = { 
	/* LDRB/STRB pc,[...]	cccc 01xx x0xx xxxx xxxx xxxx xxxx xxxx */

	DECODE_REJECT	(0x0c40f000, 0x0440f000),



	/* STRT			cccc 01x0 x010 xxxx xxxx xxxx xxxx xxxx */

	/* LDRT			cccc 01x0 x011 xxxx xxxx xxxx xxxx xxxx */

	/* STRBT		cccc 01x0 x110 xxxx xxxx xxxx xxxx xxxx */

	/* LDRBT		cccc 01x0 x111 xxxx xxxx xxxx xxxx xxxx */

	DECODE_REJECT	(0x0d200000, 0x04200000),



	/* STR (immediate)	cccc 010x x0x0 xxxx xxxx xxxx xxxx xxxx */

	/* STRB (immediate)	cccc 010x x1x0 xxxx xxxx xxxx xxxx xxxx */

	DECODE_EMULATEX	(0x0e100000, 0x04000000, emulate_str,