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 CE070569F2E; Wed, 14 Oct 2026 18:28:50 +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=1792002534; cv=none; b=ERHdNUhAWuJv8QOQcYGnPYNSnsIzTPqM+xHwqO7qloSQXg5sVJfZcE7zCQcj24ZaKhZESrdl7T73r3eTxT/oXQXBSVVRJoTYX+ISQTsBLi3nKgwI3X596elFPsgved7nRuH1nHolCn6kOHn+nhSN4YIhmnb3d0cnZSib4HgHryI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792002534; c=relaxed/simple; bh=VcxbbhpgVT0/2Wf/Y61MjutPv6aM6MUdYmZOtoctlHI=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=uEmfCwA97kgv8q7T6lH69SKZkMuBo1D9caLc3mbVCwfBvc5esU2vKtLfvvN6Tp2z5TRf2yhmTZFzNj1eDZXnG9SIaJxaypJ5pDGi+3fxsZN8BNpASC2dO+g98y3Xs03mbkGS7Hmb62LA8qsvAIA1OI8JXTOeCPYc3Zo0oZsW1Nc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=S0SZ0i+t; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="S0SZ0i+t" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 58AEE1F000C7; Wed, 14 Oct 2026 18:28:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792002530; bh=cM/V1HvSO33pz7+uP8HeiajczoeROfjpXYrJIAwtS08=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=S0SZ0i+tuN/i9C4qpe0yGsxomvwKTRXRklnvAHSgKJoBaF4g+atfV4FU6RN6wgnXr 6p1hylHnkwPUZ3uxG0nAXQBISPFoh1NLklJPGjd33sE32dBU732bAALwGGLuBcMWo/ uqx0k8kVCy/AG4ZCb+/sIfOgFBcO2qwV8IZGK0cKPGGyIY93cCNPt6aA404wm9Trmb 0q4YlpjNrykvWCvNnPu4Mo6Z2jiB3H0VOubdffHVRx2xulDh0nTlk4ljkK42IKX4AD 0MuFEcH/7HP1X+sv+Ver2czUaKXHzsNNIzNCbft/Fsyld7Btv6WMtSOhnLmyamebCy BELJ3tQDnc6Gg== From: Chuck Lever Date: Wed, 14 Oct 2026 14:28:32 -0400 Subject: [PATCH net-next v5 02/10] tls: Check for a pending signal after an empty record Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261014-tls-follow-on-v5-2-e76c301d4f05@kernel.org> References: <20261014-tls-follow-on-v5-0-e76c301d4f05@kernel.org> In-Reply-To: <20261014-tls-follow-on-v5-0-e76c301d4f05@kernel.org> To: John Fastabend , Jakub Kicinski , Sabrina Dubroca , "David S. Miller" , Paolo Abeni , Simon Horman , Chuck Lever , Dave Watson , Shuah Khan , Qingfang Deng , Eric Dumazet Cc: netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, sashiko-bot X-Mailer: b4 0.17-dev-9c833 X-Developer-Signature: v=1; a=openpgp-sha256; l=3230; i=cel@kernel.org; h=from:subject:message-id; bh=VcxbbhpgVT0/2Wf/Y61MjutPv6aM6MUdYmZOtoctlHI=; b=owEBbQKS/ZANAwAKATNqszNvZn+XAcsmYgBqz8ndtlPLm4pm0zJKhm4VppsbComzE6T3BJcfa /xX672MVNaJAjMEAAEKAB0WIQQosuWwEobfJDzyPv4zarMzb2Z/lwUCas/J3QAKCRAzarMzb2Z/ lzlsD/9L2zS741EkuwcxXXPBi6mMq4IceC9QIrbupeZCw+XSFrUIiRVhsa03vlkOwyQLR6uib9M 5RLnTlMjec7mctFwkCq9n+0Zk2BiJ1TJEHbYysIjyfeardnV7lRkfsb7zmjfBBiNyiAmN3LXlPF ev8W+ZZ/fpFcqZH49ZeQw96uysTbLpancfKXQ+wMYdp7Xnnkedrbj21nVLK6SPmGXX0nT8GbZ8i +NBcLKeO+1OgMWQWT2ZGYPH9iGLBXpU5Wr3q6pG2SNjqW5GdUiFDEJRYplsFYUUq3bsgxGUYqpr CWwhqd+5vmCRIoJ9HEyeLC4Kk2pXv7Mvcrs6OpQv6e6TeK959MUlTmsHZys9lopgw5R0gG6BG+z gMzL8BRphLt5/6M8mjIGuberjizhnyKyRHeb/pscP8FXbAS+melLlV2MgiJGgOWKlO3oN8RzHSq /bgMk2uMEn/xlo5saXZrvvOlT0YySPLvCugbEjY8WRnlTNj3nz96wYvCiv5d7E5uaoOCQIYJ0ad j+x3zy5QshjoiRYP1EeB8rOUNTcag68u5HqVRRBsZAUds1IbUipGoVBAh5UKGen9/vS5ehMV/qE SvitriZY9Ilgi1DdJC991tBrb5QDZImNhfn/72ecmtjoszRMl/B20nQdDISrQWmbhtgw9aOKyaf Kgk0W+EteTCwqwQ== X-Developer-Key: i=cel@kernel.org; a=openpgp; fpr=28B2E5B01286DF243CF23EFE336AB3336F667F97 tls_rx_rec_wait() tests signal_pending() only after it sleeps, and it skips the wait loop when a record is already parsed. tls_sw_recvmsg() calls tls_rx_rec_wait() once per record, and a zero-length application_data record does not advance either bound of the receive loop. A peer that streams such records holds the caller in recvmsg(), unresponsive to SIGKILL, for as long as they arrive. The hang has not been reproduced. Test for a pending signal in tls_sw_recvmsg() before it fetches the record after an empty one. A reader that has copied data gets the data. A nonblocking reader with a signal pending gets -EAGAIN rather than -EINTR. Pending task work alone makes signal_pending() true, and io_uring retries a nonblocking receive only on -EAGAIN. The test stays out of tls_rx_rec_wait() because tls_sw_read_sock() also calls tls_rx_rec_wait(), from callers that cannot act on a signal. Decrypt an empty record synchronously. The code at recv_end overwrites err once any record has been decrypted asynchronously. With only empty records queued, the reader then gets zero, not the errno. Fixes: c46234ebb4d1 ("tls: RX path for ktls") Reported-by: sashiko-bot Closes: https://sashiko.dev/#/patchset/20260720-tcp-read-sock-v2-0-29545d034f3c@kernel.org?part=1 Signed-off-by: Chuck Lever --- net/tls/tls_sw.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 37fcca95c046..ac4da28ed9c8 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -1824,6 +1824,7 @@ int tls_sw_recvmsg(struct sock *sk, bool is_peek = flags & MSG_PEEK; bool rx_more = false; bool released = true; + bool nodata = false; bool zc_capable; if (unlikely(flags & MSG_ERRQUEUE)) @@ -1858,6 +1859,18 @@ int tls_sw_recvmsg(struct sock *sk, struct tls_decrypt_arg darg; int to_decrypt, chunk; + /* A run of empty records advances neither loop bound, and + * tls_rx_rec_wait() tests for a signal only after it sleeps. + */ + if (nodata && signal_pending(current)) { + long timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); + + err = -EAGAIN; + if (timeo) + err = sock_intr_errno(timeo); + goto recv_end; + } + err = tls_rx_rec_wait(sk, flags & MSG_DONTWAIT, released, !!(decrypted + copied)); if (err <= 0) @@ -1874,9 +1887,12 @@ int tls_sw_recvmsg(struct sock *sk, tlm->control == TLS_RECORD_TYPE_DATA) darg.zc = true; - /* Do not use async mode if record is non-data */ + /* Do not use async mode if record is non-data, or if it + * is empty: once a record has gone async, recv_end + * discards the error that ends a run of empty records. + */ if (tlm->control == TLS_RECORD_TYPE_DATA) - darg.async = ctx->async_capable; + darg.async = ctx->async_capable && to_decrypt; else darg.async = false; @@ -1910,6 +1926,7 @@ int tls_sw_recvmsg(struct sock *sk, /* TLS 1.3 may have updated the length by more than overhead */ rxm = strp_msg(darg.skb); chunk = rxm->full_len; + nodata = !chunk; tls_rx_rec_done(ctx); if (!darg.zc) { -- 2.55.0