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 E0EE436493A for ; Sat, 30 May 2026 11:39:31 +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=1780141172; cv=none; b=KJ+Sy4oDWVZEeU7a3pHIzmDP64SB4+GHJgggzSaV6AoEsra9k+MifPJeP6RLcOw2cNIaYsmFnpXilhlJe+ALA+8QzaJWTP8fQfEXnY0yLaK2HRaTWiLO5HshnpWggK4EqTO3rKyTWiPoQJskjJVN54x14DvONn0Hn9Q/F14ZMVQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780141172; c=relaxed/simple; bh=tPuhf1ieZXBtINf2UqZNGq8DceBkVPrP1NzUJ5JlIjM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=U8AklKdxJX8DdgBAWruwQYM1WT/yegDT28WoQbVl44iVBLvLYbhqBbZhKbQ1zT9WsumBknE0XCLdjsULbYXfVnSwuh+4gujrYWD4WKkL4GQFEDukDe/WJAr0P4wxYbNRqReHOxZEe7PqpxeCB2g61S+8D4I4moSbac7kSs6x1Sw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mRe4YFBG; 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="mRe4YFBG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0F5201F00898; Sat, 30 May 2026 11:39:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780141171; bh=vf2x+gIk38Znbubxnk8gIlGklTjSBJieFYBgXT+rdYQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=mRe4YFBGApGdL/yXqjZypEel27x804UPyfXYeQylrnWKTfPGocQjQDllDWW1pjhBq fDKjQOuZOsnvGFYckzTxRSEZr+HeZsx8D+KSdOJhe0bN9PBnKBseGazSsPmVECJyQW sAv/HsRF25EvjrEzzTTAfcE0YrxjFvel4yV0vZ8STZOmllNHr1m0TRzBaL4Up2BkXm 5lHveerlPj085NbxQ77qKjRlkCDakqvZYCqe/AROJz4uDdp70OM2GAwQDfEjNKnPlC 8Ltb86yRgSAcAEA4wL5zEVj8MoDBnU6b09/2TrEkelUn+eCo5DRSJmasbhyZq+I6uT v6l1atv3aJDhA== From: Sasha Levin To: stable@vger.kernel.org Cc: Justin Iurman , Ido Schimmel , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15.y 2/2] ipv6: ioam: add NULL check for idev in ipv6_hop_ioam() Date: Sat, 30 May 2026 07:39:27 -0400 Message-ID: <20260530113927.1939561-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530113927.1939561-1-sashal@kernel.org> References: <2026052814-waggle-aerospace-72c0@gregkh> <20260530113927.1939561-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Justin Iurman [ Upstream commit d4ea0dfd75011b78cebf3808f98ac4c4f51a6fb9 ] Reported by Sashiko: The function ipv6_hop_ioam() accesses __in6_dev_get(skb->dev)->cnf.ioam6_enabled without validating the returned idev pointer. Because addrconf_ifdown() can concurrently clear dev->ip6_ptr via RCU, __in6_dev_get() can return NULL during interface teardown, which could cause a NULL pointer dereference when processing an IOAM Hop-by-Hop option. Let's add a check and use SKB_DROP_REASON_IPV6DISABLED accordingly. Fixes: 9ee11f0fff20 ("ipv6: ioam: Data plane support for Pre-allocated Trace") Cc: stable@vger.kernel.org Signed-off-by: Justin Iurman Reviewed-by: Ido Schimmel Link: https://patch.msgid.link/20260517183059.29140-1-justin.iurman@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv6/exthdrs.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c index 8ba89fc5ac0ae..8aeb9906258ce 100644 --- a/net/ipv6/exthdrs.c +++ b/net/ipv6/exthdrs.c @@ -941,14 +941,20 @@ static bool ipv6_hop_ioam(struct sk_buff *skb, int optoff) { struct ioam6_trace_hdr *trace; struct ioam6_namespace *ns; + struct inet6_dev *idev; struct ioam6_hdr *hdr; /* Bad alignment (must be 4n-aligned) */ if (optoff & 3) goto drop; + /* Does the device still have IPv6 configuration? */ + idev = __in6_dev_get(skb->dev); + if (!idev) + goto drop; + /* Ignore if IOAM is not enabled on ingress */ - if (!READ_ONCE(__in6_dev_get(skb->dev)->cnf.ioam6_enabled)) + if (!READ_ONCE(idev->cnf.ioam6_enabled)) goto ignore; /* Truncated Option header */ -- 2.53.0