From mboxrd@z Thu Jan 1 00:00:00 1970 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 B2A2EC54EAA for ; Mon, 30 Jan 2023 14:07:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237116AbjA3OHs (ORCPT ); Mon, 30 Jan 2023 09:07:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49620 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237123AbjA3OHn (ORCPT ); Mon, 30 Jan 2023 09:07:43 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B85AF3A877 for ; Mon, 30 Jan 2023 06:07:42 -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 5424D61086 for ; Mon, 30 Jan 2023 14:07:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 559A7C433D2; Mon, 30 Jan 2023 14:07:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1675087661; bh=fpReE+b5+GjmPdd6xk2PqV/Ar4GK3VsfGhgIRkBBu68=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=v4+kaJji0j6IGSjCG6TuN1D1g1QsXZP4T/JI3wHzNdRrVY49Ta7Z3ol/BGRAaCMe2 pDhgs0sEb/gbzX4+tndKmh0/CVohbh4lrk8tTdXVdExqksui7fH07ntkZV6IOR475G lIRm47nhgem0cmIPJla2BnkXlZVThoOuLBL+5XfQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Liao Chang , Guo Ren , Palmer Dabbelt , Sasha Levin Subject: [PATCH 6.1 283/313] riscv/kprobe: Fix instruction simulation of JALR Date: Mon, 30 Jan 2023 14:51:58 +0100 Message-Id: <20230130134349.908883206@linuxfoundation.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230130134336.532886729@linuxfoundation.org> References: <20230130134336.532886729@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Liao Chang [ Upstream commit ca0254998be4d74cf6add70ccfab0d2dbd362a10 ] Set kprobe at 'jalr 1140(ra)' of vfs_write results in the following crash: [ 32.092235] Unable to handle kernel access to user memory without uaccess routines at virtual address 00aaaaaad77b1170 [ 32.093115] Oops [#1] [ 32.093251] Modules linked in: [ 32.093626] CPU: 0 PID: 135 Comm: ftracetest Not tainted 6.2.0-rc2-00013-gb0aa5e5df0cb-dirty #16 [ 32.093985] Hardware name: riscv-virtio,qemu (DT) [ 32.094280] epc : ksys_read+0x88/0xd6 [ 32.094855] ra : ksys_read+0xc0/0xd6 [ 32.095016] epc : ffffffff801cda80 ra : ffffffff801cdab8 sp : ff20000000d7bdc0 [ 32.095227] gp : ffffffff80f14000 tp : ff60000080f9cb40 t0 : ffffffff80f13e80 [ 32.095500] t1 : ffffffff8000c29c t2 : ffffffff800dbc54 s0 : ff20000000d7be60 [ 32.095716] s1 : 0000000000000000 a0 : ffffffff805a64ae a1 : ffffffff80a83708 [ 32.095921] a2 : ffffffff80f160a0 a3 : 0000000000000000 a4 : f229b0afdb165300 [ 32.096171] a5 : f229b0afdb165300 a6 : ffffffff80eeebd0 a7 : 00000000000003ff [ 32.096411] s2 : ff6000007ff76800 s3 : fffffffffffffff7 s4 : 00aaaaaad77b1170 [ 32.096638] s5 : ffffffff80f160a0 s6 : ff6000007ff76800 s7 : 0000000000000030 [ 32.096865] s8 : 00ffffffc3d97be0 s9 : 0000000000000007 s10: 00aaaaaad77c9410 [ 32.097092] s11: 0000000000000000 t3 : ffffffff80f13e48 t4 : ffffffff8000c29c [ 32.097317] t5 : ffffffff8000c29c t6 : ffffffff800dbc54 [ 32.097505] status: 0000000200000120 badaddr: 00aaaaaad77b1170 cause: 000000000000000d [ 32.098011] [] ksys_write+0x6c/0xd6 [ 32.098222] [] sys_write+0x2a/0x38 [ 32.098405] [] ret_from_syscall+0x0/0x2 Since the rs1 and rd might be the same one, such as 'jalr 1140(ra)', hence it requires obtaining the target address from rs1 followed by updating rd. Fixes: c22b0bcb1dd0 ("riscv: Add kprobes supported") Signed-off-by: Liao Chang Reviewed-by: Guo Ren Link: https://lore.kernel.org/r/20230116064342.2092136-1-liaochang1@huawei.com [Palmer: Pick Guo's cleanup] Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin --- arch/riscv/kernel/probes/simulate-insn.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/riscv/kernel/probes/simulate-insn.c b/arch/riscv/kernel/probes/simulate-insn.c index d73e96f6ed7c..a20568bd1f1a 100644 --- a/arch/riscv/kernel/probes/simulate-insn.c +++ b/arch/riscv/kernel/probes/simulate-insn.c @@ -71,11 +71,11 @@ bool __kprobes simulate_jalr(u32 opcode, unsigned long addr, struct pt_regs *reg u32 rd_index = (opcode >> 7) & 0x1f; u32 rs1_index = (opcode >> 15) & 0x1f; - ret = rv_insn_reg_set_val(regs, rd_index, addr + 4); + ret = rv_insn_reg_get_val(regs, rs1_index, &base_addr); if (!ret) return ret; - ret = rv_insn_reg_get_val(regs, rs1_index, &base_addr); + ret = rv_insn_reg_set_val(regs, rd_index, addr + 4); if (!ret) return ret; -- 2.39.0