From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A3B51134A4 for ; Mon, 12 Jun 2023 10:45:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 27FACC433EF; Mon, 12 Jun 2023 10:45:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1686566708; bh=gAVA0X3ZxOMh/8sz7qPRsLRdJGgufkUvZDsAAn6A2YA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1pZIQzr7RDGYCNMwZaVD8xw2PtIJBSJ7d4+ETXWt8tsLEu/X9HvXnWkDfQZ/y7ZHD bJEsReJFjcdmCLiTXb8kjcm9YlPt5ewBWXHHvhqa5qAuh02PIqChoyLP6OmumuN8t+ yp63+Qfp5B1DEXjve4BtHLRaGrTJcA9Nl+SgyVAA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ruan Jinjie , =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , Palmer Dabbelt , Sasha Levin Subject: [PATCH 6.1 121/132] riscv: fix kprobe __user string arg print fault issue Date: Mon, 12 Jun 2023 12:27:35 +0200 Message-ID: <20230612101715.740190947@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230612101710.279705932@linuxfoundation.org> References: <20230612101710.279705932@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Ruan Jinjie [ Upstream commit 99a670b2069c725a7b50318aa681d9cae8f89325 ] On riscv qemu platform, when add kprobe event on do_sys_open() to show filename string arg, it just print fault as follow: echo 'p:myprobe do_sys_open dfd=$arg1 filename=+0($arg2):string flags=$arg3 mode=$arg4' > kprobe_events bash-166 [000] ...1. 360.195367: myprobe: (do_sys_open+0x0/0x84) dfd=0xffffffffffffff9c filename=(fault) flags=0x8241 mode=0x1b6 bash-166 [000] ...1. 360.219369: myprobe: (do_sys_open+0x0/0x84) dfd=0xffffffffffffff9c filename=(fault) flags=0x8241 mode=0x1b6 bash-191 [000] ...1. 360.378827: myprobe: (do_sys_open+0x0/0x84) dfd=0xffffffffffffff9c filename=(fault) flags=0x98800 mode=0x0 As riscv do not select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE, the +0($arg2) addr is processed as a kernel address though it is a userspace address, cause the above filename=(fault) print. So select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE to avoid the issue, after that the kprobe trace is ok as below: bash-166 [000] ...1. 96.767641: myprobe: (do_sys_open+0x0/0x84) dfd=0xffffffffffffff9c filename="/dev/null" flags=0x8241 mode=0x1b6 bash-166 [000] ...1. 96.793751: myprobe: (do_sys_open+0x0/0x84) dfd=0xffffffffffffff9c filename="/dev/null" flags=0x8241 mode=0x1b6 bash-177 [000] ...1. 96.962354: myprobe: (do_sys_open+0x0/0x84) dfd=0xffffffffffffff9c filename="/sys/kernel/debug/tracing/events/kprobes/" flags=0x98800 mode=0x0 Signed-off-by: Ruan Jinjie Acked-by: Björn Töpel Fixes: 0ebeea8ca8a4 ("bpf: Restrict bpf_probe_read{, str}() only to archs where they work") Link: https://lore.kernel.org/r/20230504072910.3742842-1-ruanjinjie@huawei.com Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin --- arch/riscv/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 06b9b2f60b9fb..a85bbe28dcf46 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -25,6 +25,7 @@ config RISCV select ARCH_HAS_GIGANTIC_PAGE select ARCH_HAS_KCOV select ARCH_HAS_MMIOWB + select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE select ARCH_HAS_PTE_SPECIAL select ARCH_HAS_SET_DIRECT_MAP if MMU select ARCH_HAS_SET_MEMORY if MMU -- 2.39.2