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 BDF744C77D2; Mon, 31 Aug 2026 13:39:01 +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=1788183543; cv=none; b=SLRequXumupydNx1JwIthZD95RJLug/rcnxmUutEG/5j0vlwnEuj0fjFHY1qzvVSqtX94t6fe8jRFdCaAXhiEDG1Ae6SshpB2wm/LkClPGCrk+3zSusiSO6c7d7vr87ivW7Y72Wb5Xfx9epHfHh5mROwYWOaSP0xAQSzEadWlg0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788183543; c=relaxed/simple; bh=LtKP96FadohPkNHth/wfxbCGnkuHIW7V/iIVyWYsKCI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BBn0jfDM5FludImrwSRd9XQ9vguyY7UC26YSaCMOM+gIwnxOVYFfEkZ/2GXm2ZFnfshffcfi30WY716dVapy5eLUnhn5CnPZL6XVRVbUSTHSuSxD8IS7ijyfTbubUuXzR+gbJvmC4SGd8H7p4kimaC5vYlSC+h04RzKp5bxEAyI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=rW+Ya2cx; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="rW+Ya2cx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 144061F00A3D; Mon, 31 Aug 2026 13:39:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788183541; bh=ZIoUuhtBhhbNrIc70rc9ZXMjJbfM3lec+lhEyTe57Fo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=rW+Ya2cxWO8HNgPN/Ojilaps4hel3NFgGSc2P3KMYRtMi9pd1zhSgAp1jMIfjPiAZ o/zz8jYzVHhLsBBS4A4qUjmny7YtAlDkULvPSpe09sX/iq9waciT2Q6ap8WCMeR0sJ vsXYJMDBpYht+oXZndm2uNPYAfmXwmgfIddFMsWA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, zdi-disclosures@trendmicro.com, Sabrina Dubroca , Breno Leitao , Steffen Klassert Subject: [PATCH 7.2 32/71] xfrm: espintcp: fix UAF during close Date: Mon, 31 Aug 2026 15:33:57 +0200 Message-ID: <20260831133400.744383916@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260831133359.055927882@linuxfoundation.org> References: <20260831133359.055927882@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sabrina Dubroca commit deb232e884877bf10b4ce2580909eedec986c284 upstream. ZDI reported and analyzed a race condition during close for espintcp sockets: espintcp_close() frees emsg->skb via kfree_skb() without holding any socket lock. Concurrently, the xfrm_trans_reinject work queue invokes esp_output_tcp_finish() -> espintcp_push_skb() -> espintcp_push_msgs() -> skb_send_sock_locked(), which reads the same skb as a data source. Fix this by adding a synchronize_rcu() call after resetting sk_prot, since esp_output_tcp_finish() runs under RCU and won't use a socket with sk_prot == &tcp_prot. Simply taking the socket lock in espintcp_close() could lead to leaks, if esp_output_tcp_finish() re-adds an skb in the slot we just freed. After this, the existing barrier() is no longer needed. Cc: stable@vger.kernel.org Fixes: e27cca96cd68 ("xfrm: add espintcp (RFC 8229)") Reported-by: zdi-disclosures@trendmicro.com Signed-off-by: Sabrina Dubroca Reviewed-by: Breno Leitao Signed-off-by: Steffen Klassert Signed-off-by: Greg Kroah-Hartman --- net/xfrm/espintcp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/xfrm/espintcp.c +++ b/net/xfrm/espintcp.c @@ -515,7 +515,8 @@ static void espintcp_close(struct sock * strp_stop(&ctx->strp); sk->sk_prot = &tcp_prot; - barrier(); + + synchronize_rcu(); disable_work_sync(&ctx->work); strp_done(&ctx->strp);