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 09BF03043C8; Tue, 16 Jun 2026 17:56:34 +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=1781632595; cv=none; b=WO/oN2MiAVDHkCeiCU4q9IjBW0ipf6t2icz+ItRPRhAHYESOuCRDySsmqV9P4agnoOMZ59SxVRIWpIfP9Ru7ZADCrCSjMHxK0Ucv6i2XyTjXqXnUJXB1Wee9czSQTEXwBlWEq0pZ+iEe56rS3lVloRAm5DoGqRxAy75q3k4TTDs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781632595; c=relaxed/simple; bh=UFyl6jESsqJf9UfDXvp2r6a+EiujMpZmDrYpJBremYg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=U9uh1MyLwzZImGRju2tSbBh+BWONYC4LphIfCZL5mXF/N26a9d9171Dl9GnipzxXqXeP8ln6JJ20jI2jq+vdf/G1sX4Qou5jA8gh48+pTIHjq6N6/uSB8cQgphR2NquvE6srP0CTa/J0UwomTiv/zy3bn3nsVGnOFkgrU0N4/F4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=iKcNsl87; 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="iKcNsl87" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C88F51F000E9; Tue, 16 Jun 2026 17:56:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781632593; bh=irC/sh9LcE70WnitiL0ng+lm1oXonRL6lpdUWnPgU1c=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=iKcNsl87PD9xYspdTWwRFMq6BrUfktHtWi0JdUJkbOpKDT9mozhov1B9VYR+tgwYW 5GwiqDJH9Xq6vXyhVTFSad+udrnQSDUWCmB+pJ+UpJ0nN+cFXjI6pH2rcT8DNa5zXd /aE3QqsfsejK9AFX0V2DrhwKWJeaEh1FWNJoEIF0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Justin Iurman , Ido Schimmel , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 439/522] ipv6: ioam: add NULL check for idev in ipv6_hop_ioam() Date: Tue, 16 Jun 2026 20:29:46 +0530 Message-ID: <20260616145146.487747866@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145125.307082728@linuxfoundation.org> References: <20260616145125.307082728@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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ 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 [ dropped READ_ONCE() wrapper from idev->cnf.ioam6_enabled ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/ipv6/exthdrs.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) --- a/net/ipv6/exthdrs.c +++ b/net/ipv6/exthdrs.c @@ -952,16 +952,27 @@ static bool ipv6_hop_ra(struct sk_buff * static bool ipv6_hop_ioam(struct sk_buff *skb, int optoff) { + enum skb_drop_reason drop_reason; struct ioam6_trace_hdr *trace; struct ioam6_namespace *ns; + struct inet6_dev *idev; struct ioam6_hdr *hdr; + drop_reason = SKB_DROP_REASON_IP_INHDR; + /* 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) { + drop_reason = SKB_DROP_REASON_IPV6DISABLED; + goto drop; + } + /* Ignore if IOAM is not enabled on ingress */ - if (!__in6_dev_get(skb->dev)->cnf.ioam6_enabled) + if (!idev->cnf.ioam6_enabled) goto ignore; /* Truncated Option header */ @@ -1011,7 +1022,7 @@ ignore: return true; drop: - kfree_skb_reason(skb, SKB_DROP_REASON_IP_INHDR); + kfree_skb_reason(skb, drop_reason); return false; }