From nobody Sun Nov 24 22:45:31 2024 Received: from mail-lf1-f42.google.com (mail-lf1-f42.google.com [209.85.167.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B7DC91D9A57 for ; Fri, 1 Nov 2024 20:42:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.42 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730493771; cv=none; b=THfetXWhnTQWRcKGmN9TeaBeVu+soAksMLnUR9zZ4VQ4VZtT4LP0fqXPM61g2Hi5fb4V33Kqk8q19/uk3UEUpAS07iNNUEKGcrTxFE1DcaS5odODcnepgquDz74rIWJBVxuIrdBg1OaqzEoE3gGxO3LEKKdidhrez8B1nPaivNQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730493771; c=relaxed/simple; bh=3QXy9050gOYncIXE+R2pbTbvmMkR4LrPZbETxEhnc74=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZuEQw7NE1m2RBBzqws0HlUTeUSd5cUtHp4L3jD9weRecRPj6E1VzItDb+8PBRsBkEkjOjuWmDogR089s6/7SoGQjUCMuOhpap2Fod2b8Iv1UnGMti9L5ryEbKSUoFhr6SYb4eDnm7kTWsWmKZi7Jv2OsfRPWKKkOlCt+VGLIBXg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=aiven.io; spf=pass smtp.mailfrom=aiven.io; dkim=pass (1024-bit key) header.d=aiven.io header.i=@aiven.io header.b=JUgBzDRf; arc=none smtp.client-ip=209.85.167.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=aiven.io Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=aiven.io Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=aiven.io header.i=@aiven.io header.b="JUgBzDRf" Received: by mail-lf1-f42.google.com with SMTP id 2adb3069b0e04-539f6e1f756so2519121e87.0 for ; Fri, 01 Nov 2024 13:42:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=aiven.io; s=google; t=1730493768; x=1731098568; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=R6TrVFfcGXD8kSbw6FXkVrEAKiZNlsByz2hfz9EP2yM=; b=JUgBzDRf3VdbAxw602f5AO/cqesxQSXFVjWckNkcsENxb0hC+M0kBU6PS1O56rBgZ4 s3T48Ytx/pcpKhCMI70dBYAEOvVk6/y1Nn64JOOMRG4Il1athqc9NJhDvAVOa/aXDNqr U3sIm15LUMhtsQQF0QGBHN9eiqtHxI3DIivBM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1730493768; x=1731098568; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=R6TrVFfcGXD8kSbw6FXkVrEAKiZNlsByz2hfz9EP2yM=; b=XWZKJNFil+oJ4DoGMHbcAPnZCBsJRgHFRqn0E6hWkAIjm7Lhp3R4P6X0r2Nb6KGtXY itTnJl52Mu+8ioCfFYgp7wJYzqostXFlTIZ5qMWljLobTm+oc5B63eA+k7aSsaRdSAMS I255yEhfVM9zTROBPfYmNn4WHuoXK4UFc5YvMWaTp4qrZsG0NGic9um/PzZNAZU82MRz XeYOGq+eWBhjl57BjzanF2kXJdgn6U8aoUZLB8p7qysp85rUt+0M5kDON9Wn7MAl9oVQ XuucT5Wvgx770HmPRvba+rsr3GIjrHZxCXv/kee23Y1NmVBShg40gNtUx9gBLf0LA2fu afyw== X-Forwarded-Encrypted: i=1; AJvYcCVETia2CeQr9CrpCSPF2YPYn3XFrfUJDSFXwQn+L+sQRosdLPVMYm1n9GsqKH6gKMi+q1sgbB2sy/jKTBQ=@vger.kernel.org X-Gm-Message-State: AOJu0YwG0yCUs8D+N/OeTm3JVwFI6joB2FpG/J9xYxUb6F4mgGc5uQtW tp8sMmd8gKwUrBbGWGKlrn1WwPjKonOStneoWmcdznkIWgsJbWbPlAysYFp92JY= X-Google-Smtp-Source: AGHT+IE8XHuHUIipKsIjnzsYkrp4r5rPxJ5bBycpbNoE6QMC5hzsweCRTY4meEyGritA1Q0D+47FRQ== X-Received: by 2002:a05:6512:398d:b0:533:711:35be with SMTP id 2adb3069b0e04-53b348e154fmr12549599e87.26.1730493767880; Fri, 01 Nov 2024 13:42:47 -0700 (PDT) Received: from ox.aiven-management.aivencloud.com (n114-74-229-70.bla3.nsw.optusnet.com.au. [114.74.229.70]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-211056edb4csm25014455ad.58.2024.11.01.13.42.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 01 Nov 2024 13:42:47 -0700 (PDT) From: Orange Kao To: tony.luck@intel.com, qiuxu.zhuo@intel.com Cc: bp@alien8.de, james.morse@arm.com, orange@kaosy.org, linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org, mchehab@kernel.org, rric@kernel.org, Orange Kao Subject: [PATCH 1/2] EDAC/igen6: Avoid segmentation fault when rmmod Date: Fri, 1 Nov 2024 20:41:13 +0000 Message-ID: <20241101204211.414664-2-orange@aiven.io> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241101204211.414664-1-orange@aiven.io> References: <20241101204211.414664-1-orange@aiven.io> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The segmentation fault happens because During modprobe: 1. In igen6_probe(), igen6_pvt will be allocated with kzalloc() 2. In igen6_register_mci(), mci->pvt_info will point to &igen6_pvt->imc[mc] During rmmod: 1. In mci_release() in edac_mc.c, it will kfree(mci->pvt_info) 2. In igen6_remove(), it will kfree(igen6_pvt); And that caused double kfree on the same memory address. My proposal is to = set mci->pvt_info to NULL to avoid double-kfree. --- drivers/edac/igen6_edac.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/edac/igen6_edac.c b/drivers/edac/igen6_edac.c index 189a2fc29e74..07dacf8c10be 100644 --- a/drivers/edac/igen6_edac.c +++ b/drivers/edac/igen6_edac.c @@ -1245,6 +1245,7 @@ static int igen6_register_mci(int mc, u64 mchbar, str= uct pci_dev *pdev) imc->mci =3D mci; return 0; fail3: + mci->pvt_info =3D NULL; kfree(mci->ctl_name); fail2: edac_mc_free(mci); @@ -1269,6 +1270,7 @@ static void igen6_unregister_mcis(void) =20 edac_mc_del_mc(mci->pdev); kfree(mci->ctl_name); + mci->pvt_info =3D NULL; edac_mc_free(mci); iounmap(imc->window); } --=20 2.47.0