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 179483B7B68 for ; Thu, 28 May 2026 09:59:18 +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=1779962360; cv=none; b=lmbt/8G3BrE5IeuqibJ9pgv77s2ASNV8mhVPdLWDmkbp8VTJ2XiQHf8Pr8fN040QNyr5OYW8h9PPq4GLesYe52rKMlulLtYpzCZMoBtxN4HYhoJ0x6VyWJoStCnY+SR5dWzx4QGFZ1FqyylhQoNQIBhGUlkTFRlTTkBD+Vv+e38= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779962360; c=relaxed/simple; bh=oPGPZ4FKATjVxFQRib1taTXepCuptTdRSjMUjotIsCg=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=RyrP4OtAy7Z50kXB2PviwlP51+Ypq/5TfpLWh8caZSyd0WCWd3zGV967HeTjBAWGa3kfXLl4sDf08PJ1V0mKClzfmgvBhOZgKYlvSVQbZV8FoRLmnxbhl+5sMHNTgj9t0EChOjRnVIfJ9JRWw7Vl9MG9RkU4e+VxEnP4h10x07s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2UWvftZ6; 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="2UWvftZ6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 323B01F000E9; Thu, 28 May 2026 09:59:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779962358; bh=y5kPemt7lYSNzzH9FprjzmZO4+duHHwnwKVF16kwj/k=; h=Subject:To:Cc:From:Date; b=2UWvftZ608QYvs428zEN1FYCenXXQDscmIvVqbkUdSqkkcRPHpevHVKYjAZCG/MxZ qbjGX9HbbQCcCepZT3snFOkYe2aN+/ugsGyAFSSwZA/0VkT/0Li8N4KCn+s2cUFg+l 4WPemZ8ylJuKGRmodKzXvXabhZIb4zjLRabTruNE= Subject: FAILED: patch "[PATCH] ipv6: ioam: add NULL check for idev in ipv6_hop_ioam()" failed to apply to 5.15-stable tree To: justin.iurman@gmail.com,idosch@nvidia.com,kuba@kernel.org Cc: From: Date: Thu, 28 May 2026 11:58:14 +0200 Message-ID: <2026052814-waggle-aerospace-72c0@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x d4ea0dfd75011b78cebf3808f98ac4c4f51a6fb9 # git commit -s git send-email --to '' --in-reply-to '2026052814-waggle-aerospace-72c0@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From d4ea0dfd75011b78cebf3808f98ac4c4f51a6fb9 Mon Sep 17 00:00:00 2001 From: Justin Iurman Date: Sun, 17 May 2026 20:30:59 +0200 Subject: [PATCH] ipv6: ioam: add NULL check for idev in ipv6_hop_ioam() 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 diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c index 03cbce842c1a..47c5502a34a2 100644 --- a/net/ipv6/exthdrs.c +++ b/net/ipv6/exthdrs.c @@ -910,16 +910,27 @@ static bool ipv6_hop_ra(struct sk_buff *skb, int optoff) 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 (!READ_ONCE(__in6_dev_get(skb->dev)->cnf.ioam6_enabled)) + if (!READ_ONCE(idev->cnf.ioam6_enabled)) goto ignore; /* Truncated Option header */ @@ -972,7 +983,7 @@ static bool ipv6_hop_ioam(struct sk_buff *skb, int optoff) return true; drop: - kfree_skb_reason(skb, SKB_DROP_REASON_IP_INHDR); + kfree_skb_reason(skb, drop_reason); return false; }