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 X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 582D6C433DB for ; Mon, 29 Mar 2021 18:21:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1811861999 for ; Mon, 29 Mar 2021 18:21:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231499AbhC2SUe (ORCPT ); Mon, 29 Mar 2021 14:20:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38964 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231441AbhC2SUM (ORCPT ); Mon, 29 Mar 2021 14:20:12 -0400 Received: from ustc.edu.cn (email6.ustc.edu.cn [IPv6:2001:da8:d800::8]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id CAF46C061574 for ; Mon, 29 Mar 2021 11:20:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mail.ustc.edu.cn; s=dkim; h=Received:Date:From:To:Cc:Subject: Message-ID:MIME-Version:Content-Type:Content-Transfer-Encoding; bh=2H4fVtt4TApMCQQTJmV0pIA+VbsTkzZwa9i3XuVB4mQ=; b=gLa7AZnuRo7cZ QNH+PBx+nKfjED/o1v+OUtRdSpCnpcd0PCHg1wd47+E+BuGuvUUL1+1O8EUfN6rj 9JFJDhZZquWZ8ADUqtBCf7Jg79GppUbsla3WFs1lsfcU303mQYxvzHX+klb5I3zs idYFgXoWBqHunS1nE79aVhJ9OxKnL8= Received: from xhacker (unknown [101.86.19.180]) by newmailweb.ustc.edu.cn (Coremail) with SMTP id LkAmygAnL0M3GmJgzehpAA--.35552S2; Tue, 30 Mar 2021 02:19:36 +0800 (CST) Date: Tue, 30 Mar 2021 02:14:40 +0800 From: Jisheng Zhang To: Paul Walmsley , Palmer Dabbelt , Albert Ou , Masami Hiramatsu , "Steven Rostedt (VMware)" , Guo Ren Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH] riscv: kprobes/ftrace: Add recursion protection to the ftrace callback Message-ID: <20210330021440.44280b7f@xhacker> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-CM-TRANSID: LkAmygAnL0M3GmJgzehpAA--.35552S2 X-Coremail-Antispam: 1UD129KBjvJXoW7KFy3Kr4xWrWxZw4rGw13CFg_yoW8XFyxpF ZFywn5tFW5AFs2ka43Ww1DWry0grs5Z3y7Gay7Ka4fJrn8Jr4Yqr1a9ayqqr17GrWYq343 AFyqyrWYka4xA37anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUyab7Iv0xC_tr1lb4IE77IF4wAFF20E14v26r4j6ryUM7CY07I2 0VC2zVCF04k26cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rw A2F7IY1VAKz4vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Gr0_Xr1l84ACjcxK6xII jxv20xvEc7CjxVAFwI0_Cr0_Gr1UM28EF7xvwVC2z280aVAFwI0_Gr1j6F4UJwA2z4x0Y4 vEx4A2jsIEc7CjxVAFwI0_Cr1j6rxdM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVAC Y4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r126r1DMcIj6I8E87Iv67AKxVWUJV W8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IY64vIr41l42xK82IYc2Ij64vIr41l4I8I 3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxV WUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAF wI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcI k0rVW3JVWrJr1lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8 JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7IU8zpB3UUUUU== X-CM-SenderInfo: xmv2xttqjtqzxdloh3xvwfhvlgxou0/ Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jisheng Zhang Currently, the riscv's kprobes(powerred by ftrace) handler is preemptible. Futher check indicates we miss something similar as the commit c536aa1c5b17 ("kprobes/ftrace: Add recursion protection to the ftrace callback"), so do similar modifications as the commit does. Fixes: 829adda597fe ("riscv: Add KPROBES_ON_FTRACE supported") Signed-off-by: Jisheng Zhang --- arch/riscv/kernel/probes/ftrace.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/arch/riscv/kernel/probes/ftrace.c b/arch/riscv/kernel/probes/ftrace.c index 17ca5e923bb0..aab85a82f419 100644 --- a/arch/riscv/kernel/probes/ftrace.c +++ b/arch/riscv/kernel/probes/ftrace.c @@ -9,10 +9,16 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip, struct kprobe *p; struct pt_regs *regs; struct kprobe_ctlblk *kcb; + int bit; + bit = ftrace_test_recursion_trylock(ip, parent_ip); + if (bit < 0) + return; + + preempt_disable_notrace(); p = get_kprobe((kprobe_opcode_t *)ip); if (unlikely(!p) || kprobe_disabled(p)) - return; + goto out; regs = ftrace_get_regs(fregs); kcb = get_kprobe_ctlblk(); @@ -45,6 +51,9 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip, */ __this_cpu_write(current_kprobe, NULL); } +out: + preempt_enable_notrace(); + ftrace_test_recursion_unlock(bit); } NOKPROBE_SYMBOL(kprobe_ftrace_handler); -- 2.31.0