From nobody Wed Apr 1 22:19:12 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 26277407567 for ; Wed, 1 Apr 2026 10:57:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775041030; cv=none; b=k0MIOEmgCocvvFIL72SHmCzQS6xnaflVn+tvGc8X/Ht5qfmwdV96jXTWb90mMOaHvtPT49ElZs3K/e9jGGmhflT4A5DHzgFt/EH+7A5T99XuLA01rWnxCfJ7z6CnYXVrxS0EJdt4MwwOvi5TgCERelCSfxpSFB8MhzMleZxJJKQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775041030; c=relaxed/simple; bh=CxAq8sxxdfWME2NDmOhfPSLnwRl2eUhJ1SjQUCVqquU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Gra8jrOet1Ap0FMiwOPZkEWhQe+/qLxyFCxFPPC3n559l80XPQqGUXfC8umN9Qk7b0PSCQJhWzkTHRyftr3OKQVC/qxoBzjCXAWEZK2MZQb/WpyWKYPE9FPW7gznimdOzqfWw1H/Qf0QjUmfhUaQhSujeaugyzG11gPKGImCG8w= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=UWQIDhj1; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="UWQIDhj1" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1775041027; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CLPucy+/KOM/ZUAst+Ut2hFjeRnIfKEjJCeuzdkhnmE=; b=UWQIDhj1GrcN0575jYxlvwumaZMH0l098QorUwMUmFCCN/fNFvrZMBXg664kyYSDq5ggml txRJFc2CTTfaLWzJMNd9oaBl0DVA3zQoB7JJREHvK6beXpIY2cezRy9yLquKbMoz3DY9xH ardTcPS31sVDEijYpzPlAdmJ/fvemGs= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-49-bP0FBl4PNSGTmG8tsx0E5g-1; Wed, 01 Apr 2026 06:57:04 -0400 X-MC-Unique: bP0FBl4PNSGTmG8tsx0E5g-1 X-Mimecast-MFC-AGG-ID: bP0FBl4PNSGTmG8tsx0E5g_1775041022 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 717D9180034E; Wed, 1 Apr 2026 10:57:02 +0000 (UTC) Received: from warthog.procyon.org.com (unknown [10.44.35.245]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id A132D1800351; Wed, 1 Apr 2026 10:56:58 +0000 (UTC) From: David Howells To: netdev@vger.kernel.org Cc: David Howells , Marc Dionne , Jakub Kicinski , "David S. Miller" , Eric Dumazet , Paolo Abeni , linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org, Alok Tiwari , Jeffrey Altman , Simon Horman , stable@kernel.org Subject: [PATCH net v4 06/15] rxrpc: Fix use of wrong skb when comparing queued RESP challenge serial Date: Wed, 1 Apr 2026 11:55:59 +0100 Message-ID: <20260401105614.1696001-7-dhowells@redhat.com> In-Reply-To: <20260401105614.1696001-1-dhowells@redhat.com> References: <20260401105614.1696001-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 Content-Type: text/plain; charset="utf-8" From: Alok Tiwari In rxrpc_post_response(), the code should be comparing the challenge serial number from the cached response before deciding to switch to a newer response, but looks at the newer packet private data instead, rendering the comparison always false. Fix this by switching to look at the older packet. Fix further[1] to substitute the new packet in place of the old one if newer and also to release whichever we don't use. Fixes: 5800b1cf3fd8 ("rxrpc: Allow CHALLENGEs to the passed to the app for = a RESPONSE") Signed-off-by: Alok Tiwari Signed-off-by: David Howells Reviewed-by: Jeffrey Altman cc: Marc Dionne cc: Eric Dumazet cc: "David S. Miller" cc: Jakub Kicinski cc: Paolo Abeni cc: Simon Horman cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org cc: stable@kernel.org Link: https://sashiko.dev/#/patchset/20260319150150.4189381-1-dhowells%40re= dhat.com [1] --- include/trace/events/rxrpc.h | 1 + net/rxrpc/conn_event.c | 5 +++-- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h index a826cd80007b..f7f559204b87 100644 --- a/include/trace/events/rxrpc.h +++ b/include/trace/events/rxrpc.h @@ -185,6 +185,7 @@ EM(rxrpc_skb_put_input, "PUT input ") \ EM(rxrpc_skb_put_jumbo_subpacket, "PUT jumbo-sub") \ EM(rxrpc_skb_put_oob, "PUT oob ") \ + EM(rxrpc_skb_put_old_response, "PUT old-resp ") \ EM(rxrpc_skb_put_purge, "PUT purge ") \ EM(rxrpc_skb_put_purge_oob, "PUT purge-oob") \ EM(rxrpc_skb_put_response, "PUT response ") \ diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c index 98ad9b51ca2c..c50cbfc5a313 100644 --- a/net/rxrpc/conn_event.c +++ b/net/rxrpc/conn_event.c @@ -557,11 +557,11 @@ void rxrpc_post_response(struct rxrpc_connection *con= n, struct sk_buff *skb) spin_lock_irq(&local->lock); old =3D conn->tx_response; if (old) { - struct rxrpc_skb_priv *osp =3D rxrpc_skb(skb); + struct rxrpc_skb_priv *osp =3D rxrpc_skb(old); =20 /* Always go with the response to the most recent challenge. */ if (after(sp->resp.challenge_serial, osp->resp.challenge_serial)) - conn->tx_response =3D old; + conn->tx_response =3D skb; else old =3D skb; } else { @@ -569,4 +569,5 @@ void rxrpc_post_response(struct rxrpc_connection *conn,= struct sk_buff *skb) } spin_unlock_irq(&local->lock); rxrpc_poke_conn(conn, rxrpc_conn_get_poke_response); + rxrpc_free_skb(old, rxrpc_skb_put_old_response); }