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 B1D255867D9 for ; Fri, 11 Sep 2026 19:56:22 +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=1789156596; cv=none; b=OZFeMGLralV3Xy1SI0v/HBlYAoqsSmsc4pW8o/5e4fG6kkZgtZk6fOVjs8nWnKcGXXBUg7MI8Qoii657xJIWYA+1nnUATo4PFe7Vw3LIExxG5BUXu9ATkcJFFTwGYYIOzcUkmBWPFDT7OxQNQT9+/1Fq0C0gw5iagmWS0VDE3qo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156596; c=relaxed/simple; bh=c01Bel1F9FRi9YuLLARau6VoGY/W9xH67mxFkhvGN78=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=YpAuDsbSbRYg4JFnWLrMMMSnj8vvyksPOgVmMcmKqJAxBRT6KLcrxNsf7XB/McPL17ifDGUALOPAFtLYwO6duC2Gcewp0GI/0FyFrr2vSiZV/+GoVorvMgiUTf0TottyFSLGr+Lg4m6YzYJ7mJ9anu+4a3Af7HgPBxwOr+prKfk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=GVhTTOuf; 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="GVhTTOuf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 09BAC1F00899; Fri, 11 Sep 2026 19:56:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789156580; bh=rNmajdJQqljC3QIpsIpKOuPP5OhJ2ClmvwBOSVqlM1M=; h=From:To:Cc:Subject:Date:Reply-To; b=GVhTTOufMwV6GOaBY7OJd8WOZdi1AU5Yhkqm2mmcae9QsPp3iIoLzv4ys4Pqk9jLd Z1912BIIHYMr7tW2Rl7MMna2g5NexwTqse6WLYZp8oMH31a4QgZPN8snm5nq6INB1u wjLG4hDiVTQjk3/f6d9j2VAT2HYXZBuKtxcgi7UM= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89565: ipip: fix skb leak in collect_md mode when metadata_dst allocation fails Date: Fri, 11 Sep 2026 21:44:14 +0200 Message-ID: <2026091124-CVE-2026-89565-6060@gregkh> X-Mailer: git-send-email 2.55.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3201; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=bWFeYEPYTsivsiRcOmTgKC4sRTyxjMkzvxw/dvQNoWE=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLIlMy51ddlmtdem/uCa2y/7lz/X8c1rPd6Jg9Zc//u 2ln/7Cf6YhlYRBkYpAVU2T5so3n6P6KQ4pehranYeawMoEMYeDiFICJ3L7HsGBR4LM5sdoy9lLS k+7elfRz6P2cFMIwz/rfLLvXFZt7DNe/+rRnzq7dzw1yPgMA X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: ipip: fix skb leak in collect_md mode when metadata_dst allocation fails In collect_md mode ipip_tunnel_rcv() returns 0 without freeing the skb when ip_tun_rx_dst() fails to allocate the metadata_dst. ipip_rcv() and mplsip_rcv() are registered as xfrm_tunnel handlers, so tunnel4_rcv() and tunnelmpls4_rcv() read the zero return as "the packet has been consumed" and do not free it either. The skb is leaked. The other tunnel drivers all dispose of the packet at this point: ip6_tunnel.c jumps to its drop label, ip_gre.c and ip6_gre.c return PACKET_REJECT, which makes gre_rcv() free the skb. Only ipip returns 0. Jump to the existing drop label instead. It frees the skb and still returns 0, so the packet keeps being reported as consumed, which is what we want here: the outer header has already been pulled, and neither the remaining handlers nor an ICMP unreachable have any use for it. Triggering this needs an ipip or mplsip tunnel in collect_md mode and an atomic allocation failure, which is why it has gone unnoticed. The Linux kernel CVE team has assigned CVE-2026-89565 to this issue. Affected and fixed versions =========================== Issue introduced in 4.9 with commit cfc7381b3002756b1dcada32979e942aa3126e31 and fixed in 6.12.109 with commit 6d8c5b266d0035a061573843a7243be068eb6118 Issue introduced in 4.9 with commit cfc7381b3002756b1dcada32979e942aa3126e31 and fixed in 6.18.50 with commit 31e4be21dacee49395013caae28576484a049a4f Issue introduced in 4.9 with commit cfc7381b3002756b1dcada32979e942aa3126e31 and fixed in 7.2.4 with commit fd01f1a3ed4a189a784654f7c69eb565872f2e12 Issue introduced in 4.9 with commit cfc7381b3002756b1dcada32979e942aa3126e31 and fixed in 7.3-rc1 with commit 6776efe4a52f289a3fc18f8adf19b035a7d8e1bb Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-89565 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: net/ipv4/ipip.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/6d8c5b266d0035a061573843a7243be068eb6118 https://git.kernel.org/stable/c/31e4be21dacee49395013caae28576484a049a4f https://git.kernel.org/stable/c/fd01f1a3ed4a189a784654f7c69eb565872f2e12 https://git.kernel.org/stable/c/6776efe4a52f289a3fc18f8adf19b035a7d8e1bb