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 E44A946D0BD; Thu, 20 Aug 2026 16:29:40 +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=1787243382; cv=none; b=WbDNJ/rN/ioViZsxDaLwshJMA0+9uZGL0zhYxoMToEJ9mcan1+ZhxSCwrGHLS4fC/6nqcW886yco8aX/uUu/TZJW/WGhvm9edQFO2mjzZ9sVooVxojgkMT22vm8yqt4HcOptMTC6MAgasi2+bmFZ3teZGL2tyFC/HVTuTnBKiqU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787243382; c=relaxed/simple; bh=RvMaOgNRLC4dL1HNZlz6nFJ/VfU2FEuxFra6yYF9KxQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EffQzn8LdTYZBG58IFYgybyqT5KviBmithTyUiq5ub7G0DFXacfMqngISsVIALSF2x2VH7iTaMjPyhiKjLq5kKRfQLX35Pe1XQzPdXXvLgsZ4bLs0QMRkHeAcAIAF+8c+NsZMeuw12z5JA1G7WJ9jxpERg1+nEcrHLNxBx79Nc4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=iOgSxozt; 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="iOgSxozt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 029871F000E9; Thu, 20 Aug 2026 16:29:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787243380; bh=Euj0GdicmXdCglgpXmLbZ/0CdBxqACpuC0ua7IaatHI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=iOgSxoztWkpV3nXA6BkedCuhOKMeRQcH2rKrm87U1n9mPvFGLxRyGixdJP24hMB3g u/VNFvrsXJ1mWlfJX5Rcgn7fsJ4tPBS9vax6eQLQG1uIQyGUPj4VgFJ79Tl/Kyg1dx 6BO/CR4DvwRznWvRy0kjxWkYnkcfRHTVN5um6hkE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Pei Xiao , Ulf Hansson Subject: [PATCH 5.15 036/272] mmc: atmel-mci: Fix use-after-free in atmci_remove due to race condition Date: Thu, 20 Aug 2026 16:53:40 +0200 Message-ID: <20260820145232.310218270@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260820145231.229664293@linuxfoundation.org> References: <20260820145231.229664293@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pei Xiao commit c125ee35a49a0518521b52b27631eef061b8719a upstream. In atmci_probe, &host->bh_work is bound with atmci_work_func, and atmci_interrupt, atmci_timeout_timer and atmci_dma_complete can all queue this work on system_bh_wq. If we remove the module, atmci_remove makes cleanup and the memory allocated for host with devm_kzalloc() is released after the remove callback returns, while the work mentioned above may still be pending or running. The sequence of operations that may lead to a UAF bug is as follows: CPU0 CPU1 | atmci_interrupt | queue_work(system_bh_wq, | &host->bh_work) atmci_remove | atmci_cleanup_slot(...) | atmci_writel(host, ATMCI_IDR, ~0UL) | timer_delete_sync(&host->timer) | dma_release_channel(host->dma.chan) | free_irq(platform_get_irq(pdev, 0), host) | | atmci_work_func | // use host // devm resources released after | // remove returns, host is freed | | // use host (use-after-free) Fix it by canceling the work after all the sources that can schedule it (IRQ handler, timeout timer and DMA completion callback) have been stopped, and before proceeding with the remaining cleanup in atmci_remove. Fixes: 7d2be0749a59 ("atmel-mci: Driver for Atmel on-chip MMC controllers") Assisted-by: Codex:deepseek-v4-flash Signed-off-by: Pei Xiao Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/host/atmel-mci.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/mmc/host/atmel-mci.c +++ b/drivers/mmc/host/atmel-mci.c @@ -2629,6 +2629,8 @@ static int atmci_remove(struct platform_ free_irq(platform_get_irq(pdev, 0), host); + cancel_work_sync(&host->bh_work); + clk_disable_unprepare(host->mck); pm_runtime_disable(&pdev->dev);