From patchwork Fri Oct 6 11:11:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Schmidt X-Patchwork-Id: 13411288 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B532E125B7 for ; Fri, 6 Oct 2023 11:12:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="TLoyqbf7" Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 80260DE for ; Fri, 6 Oct 2023 04:12:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1696590765; 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=zdojGdWffE+9Cjf10X0GBcdJQoHBIFt/nxLMEOIXvf4=; b=TLoyqbf7kU9OMCImwX9400DK64zDwLljX032QgbZfrKiUO3q85dBOL9NZB/wTYj7utIn6P 036wb6XpW+l4UDppfj8mcMwXKtSmF6kRcHyMDipEOvCGLgkGlSmdlWUXRCPMBmQCGH2Y2k hEdGiAVaS/5ELgHY6s/FFkYrorDn8Cw= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-55-cq16Oen1MAqn3zhjzEFw0w-1; Fri, 06 Oct 2023 07:12:27 -0400 X-MC-Unique: cq16Oen1MAqn3zhjzEFw0w-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id F410E3C11C64; Fri, 6 Oct 2023 11:12:26 +0000 (UTC) Received: from localhost.localdomain (unknown [10.45.226.36]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7EEE42027045; Fri, 6 Oct 2023 11:12:25 +0000 (UTC) From: Michal Schmidt To: intel-wired-lan@lists.osuosl.org Cc: netdev@vger.kernel.org, Jeff Kirsher , Shannon Nelson , Tony Nguyen , Jesse Brandeburg Subject: [PATCH net] i40e: prevent crash on probe if hw registers have invalid values Date: Fri, 6 Oct 2023 13:11:39 +0200 Message-ID: <20231006111139.1560132-1-mschmidt@redhat.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, RCVD_IN_DNSWL_BLOCKED,RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: kuba@kernel.org The hardware provides the indexes of the first and the last available queue and VF. From the indexes, the driver calculates the numbers of queues and VFs. In theory, a faulty device might say the last index is smaller than the first index. In that case, the driver's calculation would underflow, it would attempt to write to non-existent registers outside of the ioremapped range and crash. I ran into this not by having a faulty device, but by an operator error. I accidentally ran a QE test meant for i40e devices on an ice device. The test used 'echo i40e > /sys/...ice PCI device.../driver_override', bound the driver to the device and crashed in one of the wr32 calls in i40e_clear_hw. Add checks to prevent underflows in the calculations of num_queues and num_vfs. With this fix, the wrong device probing reports errors and returns a failure without crashing. Fixes: 838d41d92a90 ("i40e: clear all queues and interrupts") Signed-off-by: Michal Schmidt Reviewed-by: Simon Horman Tested-by: Pucha Himasekhar Reddy (A Contingent worker at Intel) --- drivers/net/ethernet/intel/i40e/i40e_common.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e_common.c b/drivers/net/ethernet/intel/i40e/i40e_common.c index eeef20f77106..1b493854f522 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_common.c +++ b/drivers/net/ethernet/intel/i40e/i40e_common.c @@ -1082,7 +1082,7 @@ void i40e_clear_hw(struct i40e_hw *hw) I40E_PFLAN_QALLOC_FIRSTQ_SHIFT; j = (val & I40E_PFLAN_QALLOC_LASTQ_MASK) >> I40E_PFLAN_QALLOC_LASTQ_SHIFT; - if (val & I40E_PFLAN_QALLOC_VALID_MASK) + if (val & I40E_PFLAN_QALLOC_VALID_MASK && j >= base_queue) num_queues = (j - base_queue) + 1; else num_queues = 0; @@ -1092,7 +1092,7 @@ void i40e_clear_hw(struct i40e_hw *hw) I40E_PF_VT_PFALLOC_FIRSTVF_SHIFT; j = (val & I40E_PF_VT_PFALLOC_LASTVF_MASK) >> I40E_PF_VT_PFALLOC_LASTVF_SHIFT; - if (val & I40E_PF_VT_PFALLOC_VALID_MASK) + if (val & I40E_PF_VT_PFALLOC_VALID_MASK && j >= i) num_vfs = (j - i) + 1; else num_vfs = 0;