From patchwork Wed Jul 26 18:29:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ira Weiny X-Patchwork-Id: 13328428 X-Patchwork-Delegate: bhelgaas@google.com 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 DA998C0015E for ; Wed, 26 Jul 2023 18:29:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229630AbjGZS3p (ORCPT ); Wed, 26 Jul 2023 14:29:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33114 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229562AbjGZS3p (ORCPT ); Wed, 26 Jul 2023 14:29:45 -0400 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20817213A; Wed, 26 Jul 2023 11:29:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1690396184; x=1721932184; h=from:date:subject:mime-version:content-transfer-encoding: message-id:to:cc; bh=2UugmXYB/i6kxbLyCIwBGxYk5WEtjViQvhva6LrKcZ8=; b=e6Hf/Ru1nrHvMkJdHviHRLU5D7Mx9xBWAPz+h9EGjCTF+SWu+hy96QZQ +ay7rvQU24+k8mrcli6C5C1pAf6Qk7oPtFW8IHbyDgxSnjXDZEjFZ0+xQ Hz72gvsE3LZzgnm4cQ/WpqA0dM1Jqj7Fn0Ird3yakkH1VIo6ZcQSU0TL9 g7qn715nmFGlkcjAdF8txWF5r/EzQO7/nCA8lD6ahpH2asd/6DKOzcYDs U7CoU2fadAJK5Cy9HVb69mVQKgKAsmzo7/mKHlvRQtrWxxDSPYZI00dF8 7jL/0DspqG/WcEtZGSFDpAyFGMOOUxpmdHlunB0W+HQ61QK74Ly7J7OlS w==; X-IronPort-AV: E=McAfee;i="6600,9927,10783"; a="358097126" X-IronPort-AV: E=Sophos;i="6.01,232,1684825200"; d="scan'208";a="358097126" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Jul 2023 11:29:43 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10783"; a="796685529" X-IronPort-AV: E=Sophos;i="6.01,232,1684825200"; d="scan'208";a="796685529" Received: from iweiny-mobl.amr.corp.intel.com (HELO localhost) ([10.212.97.167]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Jul 2023 11:29:43 -0700 From: Ira Weiny Date: Wed, 26 Jul 2023 11:29:42 -0700 Subject: [PATCH] PCI/DOE: Fix destroy_work_on_stack() race MIME-Version: 1.0 Message-Id: <20230726-doe-fix-v1-1-af07e614d4dd@intel.com> X-B4-Tracking: v=1; b=H4sIABVmwWQC/x3NwQqDQAyE4VeRnBuwa6u1ryI9RJ3VHLqWRKQgv nvXHn/mg9nJYQqnZ7GTYVPXJeW4XgoaZkkTWMfcFMpQlU2oeVzAUb8c7017q2ILeQTKuhcH9yZ pmE//Fl9h5/AxZP+/6F7H8QMFUKircgAAAA== To: Bjorn Helgaas , Dan Williams , Jonathan Cameron , Lukas Wunner , Davidlohr Bueso Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Ira Weiny X-Mailer: b4 0.13-dev-c6835 X-Developer-Signature: v=1; a=ed25519-sha256; t=1690396182; l=2634; i=ira.weiny@intel.com; s=20221211; h=from:subject:message-id; bh=2UugmXYB/i6kxbLyCIwBGxYk5WEtjViQvhva6LrKcZ8=; b=GGm4zVVuZ0rQJCHxxpdw9IG6KWDuY6e3e3wvOSZ6PSc5nfExk5Q7aWs3zLf4MGtYts7Xbv17H MYyeMY9tSM0Cs1iGhibASlW/kJcu+sXF2+7Acokaoa16UwBkgpwIsI7 X-Developer-Key: i=ira.weiny@intel.com; a=ed25519; pk=noldbkG+Wp1qXRrrkfY1QJpDf7QsOEthbOT7vm0PqsE= Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The following debug object splat was observed in testing. [ 14.061937] ------------[ cut here ]------------ [ 14.063899] ODEBUG: free active (active state 0) object: 0000000097d23782 object type: work_struct hint: doe_statemachine_work+0x0/0x510 [ 14.067480] WARNING: CPU: 1 PID: 71 at lib/debugobjects.c:514 debug_print_object+0x7d/0xb0 ... [ 14.080951] Workqueue: pci 0000:36:00.0 DOE [1 doe_statemachine_work [ 14.083485] RIP: 0010:debug_print_object+0x7d/0xb0 ... [ 14.116231] Call Trace: [ 14.117652] [ 14.118958] ? debug_print_object+0x7d/0xb0 [ 14.120782] ? __warn+0x7d/0x130 [ 14.122399] ? debug_print_object+0x7d/0xb0 [ 14.123746] ? report_bug+0x18d/0x1c0 [ 14.125025] ? handle_bug+0x3c/0x80 [ 14.126506] ? exc_invalid_op+0x13/0x60 [ 14.127796] ? asm_exc_invalid_op+0x16/0x20 [ 14.129380] ? debug_print_object+0x7d/0xb0 [ 14.130688] ? debug_print_object+0x7d/0xb0 [ 14.131997] ? __pfx_doe_statemachine_work+0x10/0x10 [ 14.133597] debug_object_free.part.0+0x11b/0x150 [ 14.134940] doe_statemachine_work+0x45e/0x510 [ 14.136348] process_one_work+0x1d4/0x3c0 ... [ 14.161484] [ 14.162434] ---[ end trace 0000000000000000 ]--- This occurs because destroy_work_on_stack() was called after signaling the completion in the calling thread. This creates a race between destroy_work_on_stack() and the task->work struct going of scope in the pci_doe(). Signal the work complete after destroying the work struct. This is safe because signal_task_complete() is the final thing the work item does and the workqueue code is careful not to access the work struct after. Fixes: abf04be0e707 ("PCI/DOE: Fix memory leak with CONFIG_DEBUG_OBJECTS=y") Cc: Lukas Wunner Signed-off-by: Ira Weiny Reviewed-by: Lukas Wunner Acked-by: Bjorn Helgaas Acked-by: Dan Williams --- drivers/pci/doe.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- base-commit: 20ea1e7d13c1b544fe67c4a8dc3943bb1ab33e6f change-id: 20230726-doe-fix-f57943f9ea82 Best regards, diff --git a/drivers/pci/doe.c b/drivers/pci/doe.c index 1b97a5ab71a9..e3aab5edaf70 100644 --- a/drivers/pci/doe.c +++ b/drivers/pci/doe.c @@ -293,8 +293,8 @@ static int pci_doe_recv_resp(struct pci_doe_mb *doe_mb, struct pci_doe_task *tas static void signal_task_complete(struct pci_doe_task *task, int rv) { task->rv = rv; - task->complete(task); destroy_work_on_stack(&task->work); + task->complete(task); } static void signal_task_abort(struct pci_doe_task *task, int rv)