Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A550AC05027 for ; Thu, 2 Feb 2023 08:32:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232406AbjBBIcx (ORCPT ); Thu, 2 Feb 2023 03:32:53 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231899AbjBBIc1 (ORCPT ); Thu, 2 Feb 2023 03:32:27 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4DFB068129 for ; Thu, 2 Feb 2023 00:32:17 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id ACDFB619E5 for ; Thu, 2 Feb 2023 08:32:16 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A1CADC433EF; Thu, 2 Feb 2023 08:32:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675326736; bh=em+SA8bH+Ubycp8Mf1txaZ7e8DD8A60wBth/RmYKOBc=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=u+5WKahB1r6X27Df3qzWXCmH1Ssws9qhIS5elNMhpfG2fNEd5hBYm41/xm5JERarP SQgY3E1J+aLBWYsYOZvSfZvx3LCMBi7OvW7IUz2q9e2x3LDxsC9WMRFZcrPVB8X9Oa sSr/Vyfww9U2vUMKQpwMW8sHYozZrHPR8fPWNmJCQtCqEIl+NtfSjxcDJWIvQsvc17 44m+xq/z2kFk1L6zaJ84niYG19C/uMgK83+/k7C2mzHRwjJb7ARXUj3i77KUaEPJok ClHfWe8w9UFlQNs9hehcNpne1OrBFmflqvqWIWGhtT7nt9wG4LmOqOVlMnsWrKqPTK ptIANM7k7Gg+Q== From: =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= To: Guo Ren Cc: palmer@dabbelt.com, paul.walmsley@sifive.com, mhiramat@kernel.org, conor.dooley@microchip.com, penberg@kernel.org, mark.rutland@arm.com, liaochang , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Guo Ren Subject: Re: [PATCH] riscv: kprobe: Fixup kernel panic when probing an illegal position In-Reply-To: References: <20230126130509.1418251-1-guoren@kernel.org> <878rhig9zj.fsf@all.your.base.are.belong.to.us> <87357pravt.fsf@all.your.base.are.belong.to.us> Date: Thu, 02 Feb 2023 09:32:13 +0100 Message-ID: <87ilgk79iq.fsf@all.your.base.are.belong.to.us> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Guo Ren writes: >> > - tmp += GET_INSN_LENGTH(*(kprobe_opcode_t *)tmp); >> > + memcpy(&opcode, (void *)tmp, sizeof(kprobe_opcode_t)); >> > + tmp += GET_INSN_LENGTH(opcode); >> >> I'd prefer sizeof(opcode). > prefer sizeof(opcode) = 4 > > GET_INSN_LENGTH(opcode) returns 2 or 4; Sorry for being unclear. I was referring to the sizeof in the memcpy.