From nobody Mon May 11 02:55:52 2026 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 00ECBC433F5 for ; Sun, 17 Apr 2022 18:53:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234861AbiDQS4X (ORCPT ); Sun, 17 Apr 2022 14:56:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54050 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233135AbiDQS4T (ORCPT ); Sun, 17 Apr 2022 14:56:19 -0400 Received: from gnuweeb.org (gnuweeb.org [51.81.211.47]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2FA943389F; Sun, 17 Apr 2022 11:53:43 -0700 (PDT) Received: from integral2.. (unknown [36.80.217.41]) by gnuweeb.org (Postfix) with ESMTPSA id E52677E3BA; Sun, 17 Apr 2022 18:53:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gnuweeb.org; s=default; t=1650221622; bh=RFtg7BoSogQqJ3qbQ59LPrzum9EvKnWpLcNv0rGtvq4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TOckYunLQZjhX4jkNkwEBU6Fu58iOoK+pPju0G/wx7MeE2Vq447MB/8GxGr3KSMZF J9ubO04ANLIdrJJ5R7/+vsuI9tjy4zota8pnaBCU5BiQ2i5OV+VFDGJAORjSigPjOZ Zm5JP0MTHQiMXhWj+2cfxPhVMpLW0FnstSBU/z3NTrPdrevEgxMrITMOAnMplf3Y0K 6mbVWZKhKOtAQqnyOJ6DUBrA8PH8K73Wifr4I1caXtk+Sjrg1yfe1vYOSOxcp9x7X1 dV1ghdR/2y3zIerlNeyv5mM/kIhN2X21m7zfHrQ2tq2bNxZwMOQ35wJe96oVeFOZ/u fMnL/23Z1NWZA== From: Ammar Faizi To: Steven Rostedt , Ingo Molnar Cc: Ammar Faizi , GNU/Weeb Mailing List , Linux Kernel Mailing List , Linux Trace Devel Mailing List Subject: [PATCH 1/2] tracing: Return -EINVAL if WARN_ON(!glob) triggered in event_hist_trigger_parse() Date: Mon, 18 Apr 2022 01:53:22 +0700 Message-Id: <20220417185323.198034-2-ammarfaizi2@gnuweeb.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220417185323.198034-1-ammarfaizi2@gnuweeb.org> References: <20220417185323.198034-1-ammarfaizi2@gnuweeb.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" If `WARN_ON(!glob)` is ever triggered, we will still continue executing the next lines. This will trigger the more serious problem, a NULL pointer dereference bug. Just return -EINVAL if @glob is NULL. Signed-off-by: Ammar Faizi --- kernel/trace/trace_events_hist.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_h= ist.c index 44db5ba9cabb..0b99ad68e3fa 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -6186,7 +6186,8 @@ static int event_hist_trigger_parse(struct event_comm= and *cmd_ops, =20 lockdep_assert_held(&event_mutex); =20 - WARN_ON(!glob); + if (WARN_ON(!glob)) + return -EINVAL; =20 if (strlen(glob)) { hist_err_clear(); --=20 Ammar Faizi From nobody Mon May 11 02:55:52 2026 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 0BB56C433F5 for ; Sun, 17 Apr 2022 18:53:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234871AbiDQS40 (ORCPT ); Sun, 17 Apr 2022 14:56:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54086 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234854AbiDQS4V (ORCPT ); Sun, 17 Apr 2022 14:56:21 -0400 Received: from gnuweeb.org (gnuweeb.org [51.81.211.47]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A570C338A1; Sun, 17 Apr 2022 11:53:45 -0700 (PDT) Received: from integral2.. (unknown [36.80.217.41]) by gnuweeb.org (Postfix) with ESMTPSA id 5421E7E3B9; Sun, 17 Apr 2022 18:53:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gnuweeb.org; s=default; t=1650221625; bh=W/B15O4/x8QrATxnTZ+KI9F1A5LySUR4+bRcaz8u5yU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HfyehUHfpp5Os+sZQK97eIpUXTHlO290GdmSLtWean27Up+3D0nCTYoIZWEhd6lmJ dqFw4s1PaXSHawNOG/P03ZIh8vUGLn3K7fKgReNAilj4xTMYrPZF5AEw8M8USkPsZW Kigh+1werbkzoIg7h49+lkLTiVtPRfk9UWSdlxMWoGSpaVJ1bBUAXoU2RPw9FYc9X7 dNMVeezqsIiUj1nx79pS/QoL95azi1JM0vAbjXqGcsRhNN5GqPhWK/nrK2eH1Tnlww BngpQYxzRlRQ9r6LLBlALpTg4aSGWPN4l1OVbLO73H+/gB2h0JJn2HGJ1+KfZvTrm7 H74G82Nqq4Nbg== From: Ammar Faizi To: Steven Rostedt , Ingo Molnar Cc: Ammar Faizi , GNU/Weeb Mailing List , Linux Kernel Mailing List , Linux Trace Devel Mailing List Subject: [PATCH 2/2] tracing: Change `if (strlen(glob))` to `if (glob[0])` Date: Mon, 18 Apr 2022 01:53:23 +0700 Message-Id: <20220417185323.198034-3-ammarfaizi2@gnuweeb.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220417185323.198034-1-ammarfaizi2@gnuweeb.org> References: <20220417185323.198034-1-ammarfaizi2@gnuweeb.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" No need to traverse to the end of string. If the first byte is not a NUL char, it's guaranteed `if (strlen(glob))` is true. Signed-off-by: Ammar Faizi --- kernel/trace/trace_events_hist.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_h= ist.c index 0b99ad68e3fa..1968e497ef44 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -6189,7 +6189,7 @@ static int event_hist_trigger_parse(struct event_comm= and *cmd_ops, if (WARN_ON(!glob)) return -EINVAL; =20 - if (strlen(glob)) { + if (glob[0]) { hist_err_clear(); last_cmd_set(file, param); } --=20 Ammar Faizi