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 88D9735D5E2 for ; Tue, 17 Feb 2026 15:37:05 +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=1771342625; cv=none; b=Cs8l0Hku8o97i5ZqefRc363qG2vL7J9uk0Bu32ZSWliJ+PQWDN42s51XxXPPK80gG3xX4dvSTqMp/Ednoz/ITvbTp18lwkM1P08RaybGZNL/h/9YrjFFs4eS0M1H4i/CFVHuLpdwU/ed7nxnm+nYTyUUHHsaNbX3toFkGZeQLB0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771342625; c=relaxed/simple; bh=+hQqWLubS7KMSAh2xl7ApuJordRXcLSUhTiJ+0dEOyY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pKkKRr22SAoC/oFmH9XPxwyT099FXXN/0Odggka0OFXDK5DguQZezXs3IouibVdlcLUic0pku/0xezvkQ5y3h3W/pfkJjgruXjFcry2KX0cETLyHe9/NxjQUrQnz7ALp0YTRAce0Wmj8A7sI4hTm4P4/b/4KVsNUT0FVtJ3ty9A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IYucySqW; 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="IYucySqW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5BCDBC4CEF7; Tue, 17 Feb 2026 15:37:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1771342625; bh=+hQqWLubS7KMSAh2xl7ApuJordRXcLSUhTiJ+0dEOyY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IYucySqW6hhApWavBUynAzTlgIjd/KZXB9tNd0H9Hugk0GOxuVIeygSC0dnm5y/RO 0ursXBDrDNXT8rwbdXcsPIq9g9g9clF1cyknHPs9KbF7MFHEsv20uMq+ot2WmfvGMZ YSOwaH26NeBWttjqIhAjWWKkQUI0dzO28/AmMdCZ7HxqlSr1p7HzaXw/o3BovI6Yk5 QQ1kDqetejWokHzA4kcxBnwFMK4AnFNsNPRfBjqWejHZzxsnyO/heYod1t6HihGHSa w/jbPi8EWQFu38p/eC9fZUbdm7n3nhRsq/+fPCSXjCSnFUvfeJix3ahUJt8R9PHO4T yVxHbL45FMPSw== Date: Tue, 17 Feb 2026 15:37:01 +0000 From: Simon Horman To: Hyunwoo Kim Cc: john.fastabend@gmail.com, kuba@kernel.org, sd@queasysnail.net, davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, netdev@vger.kernel.org Subject: Re: [PATCH] net: tls: Use disable_delayed_work_sync() instead of cancel_delayed_work_sync() in tls_sw_cancel_work_tx() Message-ID: References: Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Feb 16, 2026 at 06:51:50PM +0900, Hyunwoo Kim wrote: > After cancel_delayed_work_sync() is called from tls_sk_proto_close(), > tx_work_handler() can still be scheduled from paths such as the > Delayed ACK handler or ksoftirqd. > As a result, the tx_work_handler() worker may dereference a freed > TLS object. > > To prevent this race condition, cancel_delayed_work_sync() is > replaced with disable_delayed_work_sync(). > > Fixes: f87e62d45e51 ("net/tls: remove close callback sock unlock/lock around TX work flush") > Signed-off-by: Hyunwoo Kim Hi Hyunwoo, Thanks for your patch(es). Some feedback on process from my side. You can read more about that at https://docs.kernel.org/process/maintainer-netdev.html * I think it would be good to mention how this problem was found. * As a bug fix for code present in the net tree, it should be targeted at that tree like this. Subject: [PATCH net]: ... * Looking over git history, it seems that an appropriate prefix for patches for this code is 'tls: ' Subject [PATCH net]: tls: ... * Also, please try to make the subject a bit more succinct > --- > net/tls/tls_sw.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c > index 9937d4c810f2..b1fa62de9dab 100644 > --- a/net/tls/tls_sw.c > +++ b/net/tls/tls_sw.c > @@ -2533,7 +2533,7 @@ void tls_sw_cancel_work_tx(struct tls_context *tls_ctx) > > set_bit(BIT_TX_CLOSING, &ctx->tx_bitmask); > set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask); > - cancel_delayed_work_sync(&ctx->tx_work.work); > + disable_delayed_work_sync(&ctx->tx_work.work); > } > > void tls_sw_release_resources_tx(struct sock *sk) > -- > 2.43.0 > --- > > Dear, > > The following is a simplified scenario illustrating how each race can occur. Since tls_sw_cancel_work_tx() does not hold lock_sock(), it can race with tls_write_space(). > ``` > cpu0 cpu1 > > tls_sk_proto_close() > tls_sw_cancel_work_tx() > tls_write_space() > tls_sw_write_space() > if (!test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask)) > set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask); > cancel_delayed_work_sync(&ctx->tx_work.work); > schedule_delayed_work(&tx_ctx->tx_work.work, 0); > ``` I think that the text above would be best included in the patch description. At least for me it is fundamental to understanding the problem. > > Best regards, > Hyunwoo Kim > I see three similar patches on the mailing list. The comments above go for them too. And It would probably be useful to just handle one at a time, to allow for proper feedback. Or bundle them in a patchset. -- pw-bot: changes-requested