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 68A422D9798; Sun, 1 Mar 2026 01:39:00 +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=1772329140; cv=none; b=lYaGCJWe1w6CK/9aN0AE6u55nHR7ooIXCR8eiUOvrGkpP2PRFB4WCBtXK6epHnKN9koNT9VirJH+JaqRnV/8PKeekXqZgksajNhBlINAYDnz59Xcm9+fRa9Lpc36+HpzPuhMsfrggjaRM3vhd5wUQ3pdIunIAuYfd/00t4vtlZo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772329140; c=relaxed/simple; bh=5zZBWc4+MMNO6TCIa/a30QL812Llyass7IEU/aIMgd0=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=CeDADkG4N0NDwuHy7oNLn4qKzxuBt/uoY80tURbJdIZijIijV+ycc5BpL+Ge/jpd3nuRaqvezDOMeoFPdoHWMRrjFHctOym6Gb1hqQNkl3hM9OZzoWA6LpexcSgIAZOWK7DXABR7C0KFsfGZQ4iV50SDYGWMPan5e8tBYW1ZCKQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=grbuYWtq; 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="grbuYWtq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7CF43C19421; Sun, 1 Mar 2026 01:38:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772329140; bh=5zZBWc4+MMNO6TCIa/a30QL812Llyass7IEU/aIMgd0=; h=From:To:Cc:Subject:Date:From; b=grbuYWtqUITJ/SczW9vyWlAKJb3/y+VAr/wGdDcJoOEgaHichVY1wOjl+i1KpLQ3O K0fwQ4vPAQQm50ifDCmMOBPuhDMF6kRA+EbiJvJBT1VPYAc9yj9sAsjVp04bCYqqqU +gzSb8wHKDaSB5bRjIxGYXwhzwv7Va/2E3qKjCz6Pnu2XXszTtFe6ojiF31Lq/eXla sPdYkTHfeCXPpKEnNLU4cpR9moOecl3CMc1UkIyWBPWMtLS+hgsxlxEKkGtxjwq6f+ wRdLKeiVpNtOpTZ0MQ1uHmCe+ZxM4dlh/o95v5OetE3tTLuvRjMO/JoarFb4p3VD3s jqPbpjP4jFfZA== From: Sasha Levin To: stable@vger.kernel.org, duoming@zju.edu.cn Cc: stable@kernel.org, Jijie Shao , Simon Horman , Jakub Kicinski , linux-atm-general@lists.sourceforge.net, netdev@vger.kernel.org Subject: FAILED: Patch "atm: fore200e: fix use-after-free in tasklets during device removal" failed to apply to 6.6-stable tree Date: Sat, 28 Feb 2026 20:38:55 -0500 Message-ID: <20260301013858.1699747-1-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Hint: ignore X-stable: review Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From 8930878101cd40063888a68af73b1b0f8b6c79bc Mon Sep 17 00:00:00 2001 From: Duoming Zhou Date: Tue, 10 Feb 2026 17:45:37 +0800 Subject: [PATCH] atm: fore200e: fix use-after-free in tasklets during device removal 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 --- 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