From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 91FEF373BEC for ; Sat, 28 Feb 2026 17:58:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772301529; cv=none; b=FAu4jqglJ3mDQbawQ8O5wuyjqDPDG659bdQYNNZKtQAgpmZW2ecWh5utdVkGBAvmgMwuKmg5t2XyGOamD3KX3hUWCfWjjaYdp+8AZMo8yM5xQgKxomgfoOGtvx/En5caQj0SvqYvkJ9JAMAmmQgMbiPdGotYU+F/cML7elJh0Ug= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772301529; c=relaxed/simple; bh=DjEEaLP6mBKwe3/JXcQr75wphCCvX2O5/yn3K2hrHDc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Tuwrpe1vsdjDt4axVYnlMJXZvaxtfZd5g0qHg/Ccmb2uStJJU/DdzbgqeBn5HNPRx+fC0f+j0t9NJX3tx5nVZwdHfeODzUmWl8BG0R8L73DvORubLvvzDJHLqTmYzlIiLltSMzBp8uJq5mDX1gTvAzbxpSyxOCHzYTEBqatW5Vw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=j4hcUPiK; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="j4hcUPiK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 85686C116D0; Sat, 28 Feb 2026 17:58:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772301529; bh=DjEEaLP6mBKwe3/JXcQr75wphCCvX2O5/yn3K2hrHDc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=j4hcUPiKCSFQd1nvaarPdpfXy2hj9E84svkHIyHQLhXxFo4V5dfPn4o0KggSsvB7f p5fldLwTOIJdgaGj9M1XMhw0NujbpXKevh+lDjwQg4JGj/t+mxUUc5wSvgz7hrMhWC Lh7DC+xTzQWi2/iPxsH1e7ji+3n1hASy+90S5dgfuy1Omxqhah12qDItX8WP02+DPT v+mzpPuc2msJ1rMhmwdEHqZOOgKKvqfiS9Q9OODr/X/ym6Zw4jaXi9wJY+1NLPf/Kr Jvz7r5HhFzmWo+m4GpG77ynXx4VIXVoTmHsbcBBoCsWCrbstpmHLgtIDeFBvefYjA4 ApiC/Ay0rWyqA== From: Sasha Levin To: patches@lists.linux.dev Cc: Duoming Zhou , stable@kernel.org, Jijie Shao , Simon Horman , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.18 711/752] atm: fore200e: fix use-after-free in tasklets during device removal Date: Sat, 28 Feb 2026 12:47:02 -0500 Message-ID: <20260228174750.1542406-711-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228174750.1542406-1-sashal@kernel.org> References: <20260228174750.1542406-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Duoming Zhou [ Upstream commit 8930878101cd40063888a68af73b1b0f8b6c79bc ] When the PCA-200E or SBA-200E adapter is being detached, the fore200e is deallocated. However, the tx_tasklet or rx_tasklet may still be running or pending, leading to use-after-free bug when the already freed fore200e is accessed again in fore200e_tx_tasklet() or fore200e_rx_tasklet(). One of the race conditions can occur as follows: CPU 0 (cleanup) | CPU 1 (tasklet) fore200e_pca_remove_one() | fore200e_interrupt() fore200e_shutdown() | tasklet_schedule() kfree(fore200e) | fore200e_tx_tasklet() | fore200e-> // UAF Fix this by ensuring tx_tasklet or rx_tasklet is properly canceled before the fore200e is released. Add tasklet_kill() in fore200e_shutdown() to synchronize with any pending or running tasklets. Moreover, since fore200e_reset() could prevent further interrupts or data transfers, the tasklet_kill() should be placed after fore200e_reset() to prevent the tasklet from being rescheduled in fore200e_interrupt(). Finally, it only needs to do tasklet_kill() when the fore200e state is greater than or equal to FORE200E_STATE_IRQ, since tasklets are uninitialized in earlier states. In a word, the tasklet_kill() should be placed in the FORE200E_STATE_IRQ branch within the switch...case structure. This bug was identified through static analysis. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@kernel.org Suggested-by: Jijie Shao Signed-off-by: Duoming Zhou Reviewed-by: Jijie Shao Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260210094537.9767-1-duoming@zju.edu.cn Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/atm/fore200e.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/atm/fore200e.c b/drivers/atm/fore200e.c index f62e385714403..fec081db36dc4 100644 --- a/drivers/atm/fore200e.c +++ b/drivers/atm/fore200e.c @@ -373,6 +373,10 @@ fore200e_shutdown(struct fore200e* fore200e) fallthrough; case FORE200E_STATE_IRQ: free_irq(fore200e->irq, fore200e->atm_dev); +#ifdef FORE200E_USE_TASKLET + tasklet_kill(&fore200e->tx_tasklet); + tasklet_kill(&fore200e->rx_tasklet); +#endif fallthrough; case FORE200E_STATE_ALLOC_BUF: -- 2.51.0