From nobody Mon Jun 22 18:08:36 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 58B2FC433FE for ; Sat, 19 Mar 2022 16:52:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243672AbiCSQxd (ORCPT ); Sat, 19 Mar 2022 12:53:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46326 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240827AbiCSQxb (ORCPT ); Sat, 19 Mar 2022 12:53:31 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 8EB2D3BBF5 for ; Sat, 19 Mar 2022 09:52:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1647708729; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=saWneBVb3Kut4BG7sQxMXnQsPh0IPbc8oGB5dOPI5bM=; b=T8oOnuFFKCEc05gYbABbAR3evRih4All3igZGXHHkEz+0f6iBHuWx28TzVzFh5emtUCPTZ 5eoaNZmB5nz1uncIoMlwfKfMcYhavNpIs9UssjN3X1RKDyJ4dPUHhN3pLHe5nwBFElnGbC Ap7rzezi0h1UCC2If82X/0KAdJ5twfg= Received: from mail-qt1-f199.google.com (mail-qt1-f199.google.com [209.85.160.199]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-137-bSf2jsq2NUat2GHRwV-Z7A-1; Sat, 19 Mar 2022 12:52:08 -0400 X-MC-Unique: bSf2jsq2NUat2GHRwV-Z7A-1 Received: by mail-qt1-f199.google.com with SMTP id m21-20020ac86895000000b002e1f19fae99so4999524qtq.18 for ; Sat, 19 Mar 2022 09:52:08 -0700 (PDT) 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=saWneBVb3Kut4BG7sQxMXnQsPh0IPbc8oGB5dOPI5bM=; b=ryL3gh5cEHePICsI/2xXRhrI7xl+1u0YQbGQCW4Y7VSAaB0R3aMyjRgVZ4OJqruEF9 0/Pq3XTT4Rcy26jEjz8WRnlSVo81r7BFY81pBQbUe8yav9e3Nx+VqeSVSUr/iLtcti+I Sie9OwZ5YrDWOSZR3iAJ5BrQXrm2Qcgue4SiYx1cZooHe7aCjg3iOmBT3d6B3aJR2T52 aryGCRXhpM5UIGq4Ti7cNm0t5bX5c7kns4buwX+TjPk4SzkrTEk2t+Ce8caVGCRBXdmQ Gi12gH2xD7RRUxl/ZxVWUNFcNfNge2luHr9iNDk79H4NMKjE8hpnk5ZjlT05/z+S7u3y zTnQ== X-Gm-Message-State: AOAM530FJJEiCQ2DGkKW7mUHPVFlxzL9VsSMu0fnvUP+8B+nEOsSn54C KYwdehToT1B2JFKJ7xOusv46wUCMLLptKfJZ3JyGdxXspU7EHx6DuY8/99B12S9q7YqSgV/nLAR gqzWY6WWrl1IUOxEcAhWdHuz3 X-Received: by 2002:a05:6214:4103:b0:440:e4d1:a2a0 with SMTP id kc3-20020a056214410300b00440e4d1a2a0mr9740313qvb.42.1647708727834; Sat, 19 Mar 2022 09:52:07 -0700 (PDT) X-Google-Smtp-Source: ABdhPJw6jHqOfsabhjqcfSHg8Xl46akmD6Zgg5f+CqiERLbL97pJUpKF0JjaYcTkKZUJbiUaFmv2Ow== X-Received: by 2002:a05:6214:4103:b0:440:e4d1:a2a0 with SMTP id kc3-20020a056214410300b00440e4d1a2a0mr9740296qvb.42.1647708727655; Sat, 19 Mar 2022 09:52:07 -0700 (PDT) Received: from localhost.localdomain.com (024-205-208-113.res.spectrum.com. [24.205.208.113]) by smtp.gmail.com with ESMTPSA id t66-20020ae9df45000000b0064915aff85fsm5399938qkf.45.2022.03.19.09.52.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 19 Mar 2022 09:52:07 -0700 (PDT) From: trix@redhat.com To: jpoimboe@redhat.com, jikos@kernel.org, mbenes@suse.cz, pmladek@suse.com, joe.lawrence@redhat.com, nathan@kernel.org, ndesaulniers@google.com Cc: live-patching@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, Tom Rix Subject: [PATCH] livepatch: Reorder to use before freeing a pointer Date: Sat, 19 Mar 2022 09:51:59 -0700 Message-Id: <20220319165159.2170650-1-trix@redhat.com> X-Mailer: git-send-email 2.26.3 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" From: Tom Rix Clang static analysis reports this issue livepatch-shadow-fix1.c:113:2: warning: Use of memory after it is freed pr_info("%s: dummy @ %p, prevented leak @ %p\n", ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The pointer is freed in the previous statement. Reorder the pr_info to report before the free. Signed-off-by: Tom Rix --- samples/livepatch/livepatch-shadow-fix1.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/samples/livepatch/livepatch-shadow-fix1.c b/samples/livepatch/= livepatch-shadow-fix1.c index 918ce17b43fda..6701641bf12d4 100644 --- a/samples/livepatch/livepatch-shadow-fix1.c +++ b/samples/livepatch/livepatch-shadow-fix1.c @@ -109,9 +109,9 @@ static void livepatch_fix1_dummy_leak_dtor(void *obj, v= oid *shadow_data) void *d =3D obj; int **shadow_leak =3D shadow_data; =20 - kfree(*shadow_leak); pr_info("%s: dummy @ %p, prevented leak @ %p\n", __func__, d, *shadow_leak); + kfree(*shadow_leak); } =20 static void livepatch_fix1_dummy_free(struct dummy *d) --=20 2.26.3