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 02FA33B27DC for ; Tue, 9 Jun 2026 12:11:37 +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=1781007099; cv=none; b=TlFeVitGNCt3JiCn1/Muvv/6+73ho8II2syoPuusbfNaQrTV3Bek3GOnE8vWlmr3Dt6kpxi1MU+5fTNtHJKcxoTuJCMANKLnejw3T4nx7itaLXqy4h5rDypd/BiTq9CfRvI0swmtZW5H8kNSJ6ehYYo3mSyfARB7wyX7eNE4hD4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781007099; c=relaxed/simple; bh=G9BaXWcenSDv4DcQ6razFHsj2OZf2jqj+wjUHKuSWLo=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=MFZ1tH+EM2a0WHRntXKAoBEJFDTkbaxWO80bH/DsQHLBz4Le8pGT98Ti3EGAvaGPjsqJE4sNWxq/h4oyswDBwS3FsWiEXiLR2iL1EntTnNQhvSg9aG+goH32XcfEhJMkFbVXaNb2rV5FroIbBnCgfcteEhkkiG4roRiWSKrc1bI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=BOTDUL5M; 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="BOTDUL5M" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ED25B1F00893; Tue, 9 Jun 2026 12:11:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781007097; bh=mkCVcpcQdiPt4bdVvmLDWCw8bXgb8njgVLovShjzaYc=; h=From:To:Cc:Subject:Date:Reply-To; b=BOTDUL5M3Y6s+Avoc2jvMufxVPXPKb0O54ISAvEC1shVGpCVG015tSMuRzO4squkQ FvZTSj0QKPsUD3EqwYRt444sJu2dsrEpgaOr+Mv78lWOZO5JHpGONdKOHS14pjW8jB /M64tspxDQjjwnKhWutqRL0RbuvIR+SrSkLeALmg= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-46321: tun: free page on short-frame rejection in tun_xdp_one() Date: Tue, 9 Jun 2026 14:10:27 +0200 Message-ID: <2026060925-CVE-2026-46321-8e46@gregkh> X-Mailer: git-send-email 2.54.0 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=3579; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=b1Kr8N3MGet5n0posUp8ozC7EvBUrJ5orpPyooRy3YU=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkaTBsrZycvDRKPkHlw7I/vqUM/9fYZx7B/6d/x6c8Bt 3AD7pmzOmJZGASZGGTFFFm+bOM5ur/ikKKXoe1pmDmsTCBDGLg4BWAic38wLOg4nryBb/8PtXfs KgUJx1SnM5fvO8ew4JbWGQajaQaXrQ03leiwVt2SDvHwAQA= 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: tun: free page on short-frame rejection in tun_xdp_one() tun_xdp_one() returns -EINVAL on a frame shorter than ETH_HLEN without freeing the page that vhost_net_build_xdp() allocated for it. tun_sendmsg() discards that -EINVAL and still returns total_len, so vhost_tx_batch() takes the success path and never frees the page; each short frame in a batch leaks one page-frag chunk. A local process that can open /dev/net/tun and /dev/vhost-net can hit this path: it attaches a tun/tap device as the vhost-net backend and feeds TX descriptors whose length minus the virtio-net header is below ETH_HLEN. Each kick leaks the page-frag chunks for that batch, and a tight submission loop exhausts host memory and triggers an OOM panic. Free the page before returning -EINVAL, matching the XDP-program error path in the same function. The Linux kernel CVE team has assigned CVE-2026-46321 to this issue. Affected and fixed versions =========================== Issue introduced in 6.11 with commit 049584807f1d797fc3078b68035450a9769eb5c3 and fixed in 6.12.93 with commit 69863ff2720a0e9871f1a5710f2a33a94217fee0 Issue introduced in 6.11 with commit 049584807f1d797fc3078b68035450a9769eb5c3 and fixed in 6.18.35 with commit 37a1c268c2c8090bf4dc552d732bd23ba36f8eb0 Issue introduced in 6.11 with commit 049584807f1d797fc3078b68035450a9769eb5c3 and fixed in 7.0.12 with commit 98c67be9eb9de72465a071949e84a3cdb8fab5a3 Issue introduced in 6.11 with commit 049584807f1d797fc3078b68035450a9769eb5c3 and fixed in 7.1-rc6 with commit f4feb1e20058e407cb00f45aff47f5b7e19a6bbf Issue introduced in 5.4.281 with commit 32b0aaba5dbc85816898167d9b5d45a22eae82e9 Issue introduced in 5.10.223 with commit 6100e0237204890269e3f934acfc50d35fd6f319 Issue introduced in 5.15.164 with commit 589382f50b4a5d90d16d8bc9dcbc0e927a3e39b2 Issue introduced in 6.1.102 with commit ad6b3f622ccfb4bfedfa53b6ebd91c3d1d04f146 Issue introduced in 6.6.43 with commit d5ad89b7d01ed4e66fd04734fc63d6e78536692a Issue introduced in 6.9.12 with commit a9d1c27e2ee3b0ea5d40c105d6e728fc114470bb Issue introduced in 6.10.2 with commit 8418f55302fa1d2eeb73e16e345167e545c598a5 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-2026-46321 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: drivers/net/tun.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/69863ff2720a0e9871f1a5710f2a33a94217fee0 https://git.kernel.org/stable/c/37a1c268c2c8090bf4dc552d732bd23ba36f8eb0 https://git.kernel.org/stable/c/98c67be9eb9de72465a071949e84a3cdb8fab5a3 https://git.kernel.org/stable/c/f4feb1e20058e407cb00f45aff47f5b7e19a6bbf