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 3BAFD15E5BB; Mon, 17 Aug 2026 14:22:11 +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=1786976532; cv=none; b=nwRo3GhUpZA79Uu31TmwOfQrDcDnutV+JbjcsPrZFBo9brIfWz/kFi78mebZMMHCF6ZqKA2tuPLxqxX9+spTF2HWSDjb+v76b5zD9hKTaQpsfQZgSu48KP86Tkw6TFgXXpzSK6CKiLzIOGwGsU7CMQ5jeVJVCQ4igZNzD5xpwuM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786976532; c=relaxed/simple; bh=rKSeJF5BwB1NPas14zvEMDTFmOuYug6iLJc2Ue3X5Vc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Elc/OpuklNFbyKBdtXgkInsLLmlaWhO/XRBqU+EtCsNYYBl4Yo58ddwtlaRsgISQkuKFXUr2kyJiVdRrVojQD87+Hr69eEKNRIHlNkEFETJycIB7EeOK5Ym/5DZYzAAto173RG+EAYbS1Q4gClQLWqec4q/I7aKSMCkvReTrpQg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=lSgSvjPx; 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="lSgSvjPx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 946281F000E9; Mon, 17 Aug 2026 14:22:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786976531; bh=YavRK3A8NbRWHSr3+O4vEzWdkWdRPOGfC2/Z59G7rtU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=lSgSvjPxRalmB6u4OXN/BTrO3iOSKGQQs5ht5+ukbl32TE+vv4MpccBO8C+XekFeJ OsEpqXieEEcN29ldzCvuwP4+qlnDa95ZI7r9fD7HRRTbYwB/XlSshQNqp08kXK0Dys h/6G7jJtqxO0kuone2KWBbXEn4sBfdZKvRoCvEWI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Daehyeon Ko <4ncienth@gmail.com>, Sabrina Dubroca , Paolo Abeni , Sasha Levin Subject: [PATCH 5.15 003/456] macsec: dont read an unset MAC header in macsec_encrypt() Date: Mon, 17 Aug 2026 15:26:33 +0200 Message-ID: <20260817132539.951594834@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132539.792407575@linuxfoundation.org> References: <20260817132539.792407575@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Daehyeon Ko <4ncienth@gmail.com> commit f5089008f90c0a7c5520dff3934e0af00adf322d upstream. macsec_encrypt() reads the Ethernet header via eth_hdr(skb) (skb->head + skb->mac_header) to memmove() the 12 source/destination MAC bytes forward and make room for the SecTAG. On the AF_PACKET SOCK_RAW + PACKET_QDISC_BYPASS transmit path the skb reaches the macsec ndo_start_xmit() with the MAC header unset, so eth_hdr(skb) resolves to skb->head + (u16)~0 and the read is out of bounds: a 12-byte heap over-read that is also emitted on the wire as the frame's outer source/destination MAC. KASAN reports a slab-out-of-bounds read in macsec_start_xmit() on 6.0; on current mainline a CONFIG_DEBUG_NET build flags it as an unset mac header in skb_mac_header(). On the TX path the L2 header is at skb->data, so use skb_eth_hdr(), added by commit 96cc4b69581d ("macvlan: do not assume mac_header is set in macvlan_broadcast()") for exactly this purpose. Fixes: c09440f7dcb3 ("macsec: introduce IEEE 802.1AE driver") Cc: stable@vger.kernel.org Signed-off-by: Daehyeon Ko <4ncienth@gmail.com> Reviewed-by: Sabrina Dubroca Link: https://patch.msgid.link/20260703083634.2035145-1-4ncienth@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Daehyeon Ko <4ncienth@gmail.com> Signed-off-by: Sasha Levin --- drivers/net/macsec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index 9b0cb78507384b..5de940761ebf1e 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -662,7 +662,7 @@ static struct sk_buff *macsec_encrypt(struct sk_buff *skb, } unprotected_len = skb->len; - eth = eth_hdr(skb); + eth = skb_eth_hdr(skb); sci_present = send_sci(secy); hh = skb_push(skb, macsec_extra_len(sci_present)); memmove(hh, eth, 2 * ETH_ALEN); -- 2.53.0