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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 38979C388F3 for ; Tue, 10 May 2022 13:48:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244831AbiEJNv1 (ORCPT ); Tue, 10 May 2022 09:51:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50720 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343550AbiEJNsN (ORCPT ); Tue, 10 May 2022 09:48:13 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0BE252B09D4; Tue, 10 May 2022 06:36:35 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CF46C618AF; Tue, 10 May 2022 13:36:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA789C385A6; Tue, 10 May 2022 13:36:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1652189793; bh=NKaUkUPhvYFyVUYBOa93qXmG/LU5ZJShTPNmiqc4ywQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jHi8u8ODStqJI7WEiQGe6DMYj/xts8dYSlhIInOFmacv5gJbEDtfqkdPBk/XESWzc BIQib24K+YyvzNdMgtzVli17Ya4umn7bEl/J57R6LZOOSMckKuW/iYdifs3DOTpxON zDHZXOAxznFdnT35xYv6kTaezKalLjOHoEvFbi0U= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hulk Robot , Wei Yongjun , Corey Minyard Subject: [PATCH 5.17 003/140] ipmi:ipmi_ipmb: Fix null-ptr-deref in ipmi_unregister_smi() Date: Tue, 10 May 2022 15:06:33 +0200 Message-Id: <20220510130741.701329627@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220510130741.600270947@linuxfoundation.org> References: <20220510130741.600270947@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Corey Minyard commit 9cc3aac42566a0021e0ab7c4e9b31667ad75b1e3 upstream. KASAN report null-ptr-deref as follows: KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:ipmi_unregister_smi+0x7d/0xd50 drivers/char/ipmi/ipmi_msghandler.c:3680 Call Trace: ipmi_ipmb_remove+0x138/0x1a0 drivers/char/ipmi/ipmi_ipmb.c:443 ipmi_ipmb_probe+0x409/0xda1 drivers/char/ipmi/ipmi_ipmb.c:548 i2c_device_probe+0x959/0xac0 drivers/i2c/i2c-core-base.c:563 really_probe+0x3f3/0xa70 drivers/base/dd.c:541 In ipmi_ipmb_probe(), 'iidev->intf' is not set before ipmi_register_smi() success. And in the error handling case, ipmi_ipmb_remove() is called to release resources, ipmi_unregister_smi() is called without check 'iidev->intf', this will cause KASAN null-ptr-deref issue. General kernel style is to allow NULL to be passed into unregister calls, so fix it that way. This allows a NULL check to be removed in other code. Fixes: 57c9e3c9a374 ("ipmi:ipmi_ipmb: Unregister the SMI on remove") Reported-by: Hulk Robot Cc: stable@vger.kernel.org # v5.17+ Cc: Wei Yongjun Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman --- drivers/char/ipmi/ipmi_msghandler.c | 5 ++++- drivers/char/ipmi/ipmi_si_intf.c | 5 +---- 2 files changed, 5 insertions(+), 5 deletions(-) --- a/drivers/char/ipmi/ipmi_msghandler.c +++ b/drivers/char/ipmi/ipmi_msghandler.c @@ -3677,8 +3677,11 @@ static void cleanup_smi_msgs(struct ipmi void ipmi_unregister_smi(struct ipmi_smi *intf) { struct ipmi_smi_watcher *w; - int intf_num = intf->intf_num, index; + int intf_num, index; + if (!intf) + return; + intf_num = intf->intf_num; mutex_lock(&ipmi_interfaces_mutex); intf->intf_num = -1; intf->in_shutdown = true; --- a/drivers/char/ipmi/ipmi_si_intf.c +++ b/drivers/char/ipmi/ipmi_si_intf.c @@ -2220,10 +2220,7 @@ static void cleanup_one_si(struct smi_in return; list_del(&smi_info->link); - - if (smi_info->intf) - ipmi_unregister_smi(smi_info->intf); - + ipmi_unregister_smi(smi_info->intf); kfree(smi_info); }