From nobody Tue Jun 30 08:09:03 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 480B9C433EF for ; Fri, 21 Jan 2022 09:57:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1379790AbiAUJ47 (ORCPT ); Fri, 21 Jan 2022 04:56:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39038 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349787AbiAUJ46 (ORCPT ); Fri, 21 Jan 2022 04:56:58 -0500 Received: from mail-pj1-x102c.google.com (mail-pj1-x102c.google.com [IPv6:2607:f8b0:4864:20::102c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 51386C061574 for ; Fri, 21 Jan 2022 01:56:58 -0800 (PST) Received: by mail-pj1-x102c.google.com with SMTP id w12-20020a17090a528c00b001b276aa3aabso13299005pjh.0 for ; Fri, 21 Jan 2022 01:56:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=d/47DffcE+c3jCAlwDovIS7aShnFPAcgmE0Cy5Af+sM=; b=GfzXzlpcW7AKcVRUxF87xbg2Ci6kIiXy4dlvZd1G5MefdT5pGLTz7lXZ1xY/Dv1avS XMRSrMTG4dxH4oB02PFc2sXQGWXqXVLznCIy3js4Wm07gitZNpDLe8nsTy6sbSQgjOJ7 O8rf2wKVksUoPHlIpGaiUz0AcFXgDFNI3rChgrgBpeA4RxtD/OLlNUFkitdrWUPeZDsc F3M+OTZgIy/aaFgSuJDhVZgfCcGUKI5UiC+ofwLE7VZ4uVlZO76VWLO1N19ai4UN1AxI cdwQnKj56rsymd4k3xTxkvUg0yKIFPt61Frat6ofUdOunI/3ddfqZOHZY/Ufb5+s4qou FlkA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=d/47DffcE+c3jCAlwDovIS7aShnFPAcgmE0Cy5Af+sM=; b=NuMZVbtWKnbnTbkBU43cejvaRkA0SzDVmqd3MHddZaU9a0xuqTDH5VEo/iZvrSHVuo 3Et1vwHzTVWsswI1R+cHeGYvurXccD7h/+nZ/1WAgp4fPg2e2rUTW4r89bMZ7wA3kwSj AqlX8/fuiHPCyQIEjq3BsbMakmt3/PoyzFq6S/dhSOhrqeKD7NsEBs5636RsY9FhON0S f9YV2WXHghDGMNkjZlgUB1Pe43Mo+faKy/tKAJ1/YBYaeksL5klj0nQcfqDhcn3tn8Ad cH2nadrnMyoNDMO0guowqSxtP6MMmLsJRMKCO+5arBVSForMinlaB+2SHsAC3/aiUbV8 Uyjw== X-Gm-Message-State: AOAM5325LatBdwRpUzm8iwmGcRA/1R+SLqlmw4SGvKX0eMZaibmArCMP bNtAs2u358YaeaiCAAKOn18= X-Google-Smtp-Source: ABdhPJyg1B3e0pwxGq2QGKT5u3wkuMfPond86NBDkcSZXSd1h6hVndqYThYV0xzAhD2mV0KmJyRkgg== X-Received: by 2002:a17:902:da8c:b0:14a:909b:c911 with SMTP id j12-20020a170902da8c00b0014a909bc911mr3224302plx.103.1642759017887; Fri, 21 Jan 2022 01:56:57 -0800 (PST) Received: from vultr.guest ([141.164.42.249]) by smtp.gmail.com with ESMTPSA id c2sm4623661pgj.63.2022.01.21.01.56.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Jan 2022 01:56:57 -0800 (PST) From: Yuntao Wang To: Steven Rostedt , Ingo Molnar Cc: linux-kernel@vger.kernel.org, Yuntao Wang Subject: [PATCH] tracing: Use strim() to remove whitespace instead of doing it manually Date: Fri, 21 Jan 2022 09:56:23 +0000 Message-Id: <20220121095623.1826679-1-ytcoode@gmail.com> X-Mailer: git-send-email 2.25.1 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" The tracing_set_trace_write() function just removes the trailing whitespace from the user supplied tracer name, but the leading whitespace should also be removed. In addition, if the user supplied tracer name contains only a few whitespace characters, the first one will not be removed using the current method, which results it a single whitespace character left in the buf. To fix all of these issues, we use strim() to correctly remove both the leading and trailing whitespace. Signed-off-by: Yuntao Wang --- kernel/trace/trace.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index a569a0cb81ee..a6e77db764cf 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -6433,7 +6433,7 @@ tracing_set_trace_write(struct file *filp, const char= __user *ubuf, { struct trace_array *tr =3D filp->private_data; char buf[MAX_TRACER_SIZE+1]; - int i; + char *name; size_t ret; int err; =20 @@ -6447,11 +6447,9 @@ tracing_set_trace_write(struct file *filp, const cha= r __user *ubuf, =20 buf[cnt] =3D 0; =20 - /* strip ending whitespace. */ - for (i =3D cnt - 1; i > 0 && isspace(buf[i]); i--) - buf[i] =3D 0; + name =3D strim(buf); =20 - err =3D tracing_set_tracer(tr, buf); + err =3D tracing_set_tracer(tr, name); if (err) return err; =20 --=20 2.35.0.rc2