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 833554EA369 for ; Tue, 3 Mar 2026 16:23:57 +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=1772555037; cv=none; b=Jg+kZ9YQ+gaBSLcySJv0jdXaEZn0S2piv/mVJp2Fw7DMoAxOCqcCXk/cfY3djzUpSVoWj8DAgnI+EFVscnIAp5JgMGkdOCjnTdiQkRhYyLPydJRIigszlGnOpnWJJ8vVWImHP1GbLLPJaJNkLsfrnWiza5pVF1QNlh+S7mW5IwE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772555037; c=relaxed/simple; bh=XHl6mEiOcEEly8oKcASCj869yOPLg5PN9DKCEVObW68=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qoHQhPRJcbu9N9PwdMqwBvhxM1g7TAN1FuuUqtuImFGqokrWLl2B58QjoHKXd1IrV45U86wibdN4NXn4bsZ9JXz4vZcs5UqUeDT99XeaI5fcdySVpzWTFnxltKM2yo/fax/RkzmZiqpbfknir5N0tp5EWg5MzTO7oaaG9/VieDA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JHYkBMuR; 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="JHYkBMuR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E873AC19422; Tue, 3 Mar 2026 16:23:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772555037; bh=XHl6mEiOcEEly8oKcASCj869yOPLg5PN9DKCEVObW68=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JHYkBMuRLyg7rhTPkJy7rwdoqcA6VfLofXhch2ZRLY0YqX90ll5v0hR2otISOUVta i9wbT3g/Ld7m+EqW41YyTX5Zqfmjo2cm6dHUgRGNQjh6Xa01g8UU7pgKb9C04buHIg YcrFhznRWzLmmOX2btSgaXilnLIg+Kv8i7QhxoJqyxZ6Q9Ma1azXZTjkyFTd9rHuPj qKw0Ab5WeZlXKAYl8WutjJxCrQAWiIwjMk18o+swHqd8GbI9H8PylRF8DvogMRmCA0 7LLvKVhjIJF7DQ1RBDBmlUuprJuGEEol0FBq4D7DEyadZvmadf+c8gYbPcGerr879f SPMhLSCrxAKiw== From: Jakub Kicinski To: davem@davemloft.net Cc: netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com, andrew+netdev@lunn.ch, horms@kernel.org, Jakub Kicinski Subject: [PATCH net 5/5] nfc: rawsock: cancel tx_work before socket teardown Date: Tue, 3 Mar 2026 08:23:45 -0800 Message-ID: <20260303162346.2071888-6-kuba@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260303162346.2071888-1-kuba@kernel.org> References: <20260303162346.2071888-1-kuba@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit In rawsock_release(), cancel any pending tx_work and purge the write queue before orphaning the socket. rawsock_tx_work runs on the system workqueue and calls nfc_data_exchange which dereferences the NCI device. Without synchronization, tx_work can race with socket and device teardown when a process is killed (e.g. by SIGKILL), leading to use-after-free or leaked references. Set SEND_SHUTDOWN first so that if tx_work is already running it will see the flag and skip transmitting, then use cancel_work_sync to wait for any in-progress execution to finish, and finally purge any remaining queued skbs. Fixes: 23b7869c0fd0 ("NFC: add the NFC socket raw protocol") Signed-off-by: Jakub Kicinski --- net/nfc/rawsock.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/net/nfc/rawsock.c b/net/nfc/rawsock.c index b049022399ae..f7d7a599fade 100644 --- a/net/nfc/rawsock.c +++ b/net/nfc/rawsock.c @@ -67,6 +67,17 @@ static int rawsock_release(struct socket *sock) if (sock->type == SOCK_RAW) nfc_sock_unlink(&raw_sk_list, sk); + if (sk->sk_state == TCP_ESTABLISHED) { + /* Prevent rawsock_tx_work from starting new transmits and + * wait for any in-progress work to finish. This must happen + * before the socket is orphaned to avoid a race where + * rawsock_tx_work runs after the NCI device has been freed. + */ + sk->sk_shutdown |= SEND_SHUTDOWN; + cancel_work_sync(&nfc_rawsock(sk)->tx_work); + rawsock_write_queue_purge(sk); + } + sock_orphan(sk); sock_put(sk); -- 2.53.0