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 8357F42B756; Tue, 31 Mar 2026 16:52:20 +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=1774975940; cv=none; b=QEq4WKiSKp1kHp+l0xIKZeOjzCj+h8eqYycLuRSHGmZjNidB3NTNuF6SyrFyVB0DOoZZPdpQs+vrXrzzdk4GiagMR685a0JAvDQkejZLBXpX2YA+Mu/O+1kxK2gbmnGYYVhh/hoYDNn7MOHOXHelLukgN7ADG21voVgMHIg6lvU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774975940; c=relaxed/simple; bh=H8UasX4+Eex1RHITByJfODaCNcwi9cjLb5awb3vg+dA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cX7uSep+rKIRXwhCEpm4ERYEuZ+0V2EEHxhfbCelcF1Wi+cIkWQeNIPNexzz+O+gkiihZiMSkD7LMnAD/92c1Zrxd02OHvSqeGsMglP3Ez8fKoNxtb5Lln9FxuRF578k7hXU0GI2jdrIq9ZVepn50rxXnb4+xi6hg7P1AcejOlQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=lNaDbL6y; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="lNaDbL6y" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 19CE0C19423; Tue, 31 Mar 2026 16:52:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1774975940; bh=H8UasX4+Eex1RHITByJfODaCNcwi9cjLb5awb3vg+dA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lNaDbL6y2NDahyPjIRuRtZmMSmgbJg5q0v8+7lk7KIhwiUjR5s9zcMpohQ+2oMkm8 G0hSMTnu5uyLGjWIZYDAt6QQVAPUV9iKF6tB29x9Ok9hfxisR8w6huOMzinfeXXYNc TH/+ytyQgOkPD4jXgYiwr/4RkRRFkZEG4iKdqKxQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Xiang Mei , Weiming Shi , Florian Westphal , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 6.12 102/244] netfilter: nf_conntrack_sip: fix use of uninitialized rtp_addr in process_sdp Date: Tue, 31 Mar 2026 18:20:52 +0200 Message-ID: <20260331161745.440026692@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260331161741.651718120@linuxfoundation.org> References: <20260331161741.651718120@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Weiming Shi [ Upstream commit 6a2b724460cb67caed500c508c2ae5cf012e4db4 ] process_sdp() declares union nf_inet_addr rtp_addr on the stack and passes it to the nf_nat_sip sdp_session hook after walking the SDP media descriptions. However rtp_addr is only initialized inside the media loop when a recognized media type with a non-zero port is found. If the SDP body contains no m= lines, only inactive media sections (m=audio 0 ...) or only unrecognized media types, rtp_addr is never assigned. Despite that, the function still calls hooks->sdp_session() with &rtp_addr, causing nf_nat_sdp_session() to format the stale stack value as an IP address and rewrite the SDP session owner and connection lines with it. With CONFIG_INIT_STACK_ALL_ZERO (default on most distributions) this results in the session-level o= and c= addresses being rewritten to 0.0.0.0 for inactive SDP sessions. Without stack auto-init the rewritten address is whatever happened to be on the stack. Fix this by pre-initializing rtp_addr from the session-level connection address (caddr) when available, and tracking via a have_rtp_addr flag whether any valid address was established. Skip the sdp_session hook entirely when no valid address exists. Fixes: 4ab9e64e5e3c ("[NETFILTER]: nf_nat_sip: split up SDP mangling") Reported-by: Xiang Mei Signed-off-by: Weiming Shi Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/nf_conntrack_sip.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c index 657839a58782a..84334537c6067 100644 --- a/net/netfilter/nf_conntrack_sip.c +++ b/net/netfilter/nf_conntrack_sip.c @@ -1040,6 +1040,7 @@ static int process_sdp(struct sk_buff *skb, unsigned int protoff, unsigned int port; const struct sdp_media_type *t; int ret = NF_ACCEPT; + bool have_rtp_addr = false; hooks = rcu_dereference(nf_nat_sip_hooks); @@ -1056,8 +1057,11 @@ static int process_sdp(struct sk_buff *skb, unsigned int protoff, caddr_len = 0; if (ct_sip_parse_sdp_addr(ct, *dptr, sdpoff, *datalen, SDP_HDR_CONNECTION, SDP_HDR_MEDIA, - &matchoff, &matchlen, &caddr) > 0) + &matchoff, &matchlen, &caddr) > 0) { caddr_len = matchlen; + memcpy(&rtp_addr, &caddr, sizeof(rtp_addr)); + have_rtp_addr = true; + } mediaoff = sdpoff; for (i = 0; i < ARRAY_SIZE(sdp_media_types); ) { @@ -1091,9 +1095,11 @@ static int process_sdp(struct sk_buff *skb, unsigned int protoff, &matchoff, &matchlen, &maddr) > 0) { maddr_len = matchlen; memcpy(&rtp_addr, &maddr, sizeof(rtp_addr)); - } else if (caddr_len) + have_rtp_addr = true; + } else if (caddr_len) { memcpy(&rtp_addr, &caddr, sizeof(rtp_addr)); - else { + have_rtp_addr = true; + } else { nf_ct_helper_log(skb, ct, "cannot parse SDP message"); return NF_DROP; } @@ -1125,7 +1131,7 @@ static int process_sdp(struct sk_buff *skb, unsigned int protoff, /* Update session connection and owner addresses */ hooks = rcu_dereference(nf_nat_sip_hooks); - if (hooks && ct->status & IPS_NAT_MASK) + if (hooks && ct->status & IPS_NAT_MASK && have_rtp_addr) ret = hooks->sdp_session(skb, protoff, dataoff, dptr, datalen, sdpoff, &rtp_addr); -- 2.51.0