From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 2CAC943F4C7; Thu, 30 Jul 2026 15:06:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785424000; cv=none; b=QYontdNPqx+jaLkbXe6t8b0Y887FZXiw8/Guu9lN9IdcbR+weogMOKr5XrpD+W+7iestkw8UDejkcylsEKyXTgdm4mqqrOk4U8YQljIxjTAQ6QvedVCHsaniIdNhNMEGQsy4+DKAan4yBHZBltPCZj8bbhspjXpL8kWN1oXz76I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785424000; c=relaxed/simple; bh=ncaY1RDXnoXvkWEq68kbZjLeoCRJqdrCLF6l3DZEXiQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=trUvekSYKI+Y8Nd6fTFMqEuRGUsC1is8u0Bze+UHmo4w1jVgCJk3JCxBuL6hvXCbOMB+0hW/WG0MSm+i0JijxocVjfiGTqPhdMyiODYFoSADQIwoTQBDtFAevPOloU97gimXQtTRJQCLNKxyc8oWj1URZU/XsTuZPjnRAUWSXWc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=cvMI7s4/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="cvMI7s4/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 883B31F000E9; Thu, 30 Jul 2026 15:06:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785423999; bh=81e2laeB/MXO3/cA2yP8PzDoXoUrUXBPlUIR7LjLclM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=cvMI7s4/beTsRhF3t2Z0o7SFkOTg7bmhJrBCrHD2Yu23XPsmngIjuy11kGgUY3Cec 3gzWQVGkdVMwD143oPpmga1leWWrwzqcOd+s1OoFRmaCgpXXaFMRvT3jrmQvVQDavD d/S2UOLBSzNfm7sA0LjeDtBcyq+tDbtWquD/GkzI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, sashiko-bot , "Nikhil P. Rao" , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.18 240/675] pds_core: fix use-after-free on workqueue during remove Date: Thu, 30 Jul 2026 16:09:30 +0200 Message-ID: <20260730141450.235882320@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141445.110192266@linuxfoundation.org> References: <20260730141445.110192266@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nikhil P. Rao [ Upstream commit 0ad134881508c36b65c1a8864f8bec53adbd3327 ] In pdsc_remove(), the workqueue is destroyed before pdsc_teardown() is called. This ordering allows two paths to queue work on the destroyed workqueue: 1. If pdsc_teardown() -> pdsc_devcmd_reset() times out, the error path in pdsc_devcmd_locked() queues health_work. 2. A NotifyQ event can trigger the ISR and queue work before free_irq() is called in pdsc_teardown(). Fix by moving destroy_workqueue() after pdsc_teardown() so the workqueue outlives every queuer; destroy_workqueue() then flushes any work still pending. Draining the queued work also requires ordering the teardown so the resources that work touches are freed last: - In pdsc_qcq_free(), after freeing the interrupt, cancel_work_sync() the queue's work and only then clear qcq->intx, so pdsc_process_adminq()'s read of qcq->intx for interrupt-credit return cannot race with the clear. - Free adminqcq before notifyqcq: the shared adminq ISR is released when adminqcq is freed, and the adminq work accesses notifyqcq, so both must be stopped before notifyqcq is freed. Fixes: 01ba61b55b20 ("pds_core: Add adminq processing and commands") Reported-by: sashiko-bot Closes: https://patchwork.kernel.org/comment/27002369/ Signed-off-by: Nikhil P. Rao Link: https://patch.msgid.link/20260714180223.1642792-3-nikhil.rao@amd.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/amd/pds_core/core.c | 14 ++++++++++---- drivers/net/ethernet/amd/pds_core/main.c | 5 +++-- 2 files changed, 13 insertions(+), 6 deletions(-) diff --git a/drivers/net/ethernet/amd/pds_core/core.c b/drivers/net/ethernet/amd/pds_core/core.c index 1978287cf275fc..d64e30a204dfcb 100644 --- a/drivers/net/ethernet/amd/pds_core/core.c +++ b/drivers/net/ethernet/amd/pds_core/core.c @@ -110,7 +110,6 @@ static void pdsc_qcq_intr_free(struct pdsc *pdsc, struct pdsc_qcq *qcq) return; pdsc_intr_free(pdsc, qcq->intx); - qcq->intx = PDS_CORE_INTR_INDEX_NOT_ASSIGNED; } static int pdsc_qcq_intr_alloc(struct pdsc *pdsc, struct pdsc_qcq *qcq) @@ -145,6 +144,12 @@ void pdsc_qcq_free(struct pdsc *pdsc, struct pdsc_qcq *qcq) pdsc_qcq_intr_free(pdsc, qcq); + /* Drain any work queued by ISR before it was freed above */ + if (qcq->work.func) + cancel_work_sync(&qcq->work); + + qcq->intx = PDS_CORE_INTR_INDEX_NOT_ASSIGNED; + if (qcq->q_base) dma_free_coherent(dev, qcq->q_size, qcq->q_base, qcq->q_base_pa); @@ -304,8 +309,11 @@ int pdsc_qcq_alloc(struct pdsc *pdsc, unsigned int type, unsigned int index, static void pdsc_core_uninit(struct pdsc *pdsc) { - pdsc_qcq_free(pdsc, &pdsc->notifyqcq); + /* Free adminqcq first: its work accesses notifyqcq, so we must + * disable its IRQ and drain its work before freeing notifyqcq. + */ pdsc_qcq_free(pdsc, &pdsc->adminqcq); + pdsc_qcq_free(pdsc, &pdsc->notifyqcq); if (pdsc->kern_dbpage) { iounmap(pdsc->kern_dbpage); @@ -478,8 +486,6 @@ void pdsc_teardown(struct pdsc *pdsc, bool removing) { if (!pdsc->pdev->is_virtfn) pdsc_devcmd_reset(pdsc); - if (pdsc->adminqcq.work.func) - cancel_work_sync(&pdsc->adminqcq.work); pdsc_core_uninit(pdsc); diff --git a/drivers/net/ethernet/amd/pds_core/main.c b/drivers/net/ethernet/amd/pds_core/main.c index c7a2eff576325f..accf3a3fe94457 100644 --- a/drivers/net/ethernet/amd/pds_core/main.c +++ b/drivers/net/ethernet/amd/pds_core/main.c @@ -436,8 +436,6 @@ static void pdsc_remove(struct pci_dev *pdev) pdsc_auxbus_dev_del(pdsc, pdsc, &pdsc->padev); timer_shutdown_sync(&pdsc->wdtimer); - if (pdsc->wq) - destroy_workqueue(pdsc->wq); mutex_lock(&pdsc->config_lock); set_bit(PDSC_S_STOPPING_DRIVER, &pdsc->state); @@ -445,6 +443,9 @@ static void pdsc_remove(struct pci_dev *pdev) pdsc_stop(pdsc); pdsc_teardown(pdsc, PDSC_TEARDOWN_REMOVING); mutex_unlock(&pdsc->config_lock); + + if (pdsc->wq) + destroy_workqueue(pdsc->wq); mutex_destroy(&pdsc->config_lock); mutex_destroy(&pdsc->devcmd_lock); -- 2.53.0