From 6560edca515e53bb2e7c637ab324313680a133f4 Mon Sep 17 00:00:00 2001 From: Amit Daniel Kachhap Date: Mon, 14 Sep 2020 14:06:55 +0530 Subject: [PATCH] arm64: kprobe: disable probe of fault prone ptrauth instruction With the addition of ARMv8.3-FPAC feature, the probe of authenticate ptrauth instructions (AUT*) may cause ptrauth fault exception in case of authenticate failure so they cannot be safely single stepped. Hence the probe of authenticate instructions is disallowed but the corresponding pac ptrauth instruction (PAC*) is not affected and they can still be probed. Also AUTH* instructions do not make sense at function entry points so most realistic probes would be unaffected by this change. Signed-off-by: Amit Daniel Kachhap Reviewed-by: Dave Martin Link: https://lore.kernel.org/r/20200914083656.21428-6-amit.kachhap@arm.com Signed-off-by: Will Deacon --- arch/arm64/kernel/insn.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c index ccc8c9e22b25..6c0de2f60ea9 100644 --- a/arch/arm64/kernel/insn.c +++ b/arch/arm64/kernel/insn.c @@ -60,16 +60,10 @@ bool __kprobes aarch64_insn_is_steppable_hint(u32 insn) case AARCH64_INSN_HINT_XPACLRI: case AARCH64_INSN_HINT_PACIA_1716: case AARCH64_INSN_HINT_PACIB_1716: - case AARCH64_INSN_HINT_AUTIA_1716: - case AARCH64_INSN_HINT_AUTIB_1716: case AARCH64_INSN_HINT_PACIAZ: case AARCH64_INSN_HINT_PACIASP: case AARCH64_INSN_HINT_PACIBZ: case AARCH64_INSN_HINT_PACIBSP: - case AARCH64_INSN_HINT_AUTIAZ: - case AARCH64_INSN_HINT_AUTIASP: - case AARCH64_INSN_HINT_AUTIBZ: - case AARCH64_INSN_HINT_AUTIBSP: case AARCH64_INSN_HINT_BTI: case AARCH64_INSN_HINT_BTIC: case AARCH64_INSN_HINT_BTIJ: -- 2.50.1