From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793187683; b=sz/R2zLu5wUB1fswlTlJciSLK6rFIjck4PHARX9FWs2e7VDT3q/IhTAajrxLayrzRSzG yKzPmpQCB3tBYPQKSCFQkCucEUI0udOHmed9FT/HCJ7vS3KspxlJFi2i1Yclc9EqyiX2e lg1JqzPIfkHq1N0vr3FP7topJE1SfuklWugWkpFTDQWoDka47TBFycsPqoJZDObXNmk8+ oeVfYHdXSWboOLnbczthEzRTmsGPrPSby5q0gYQkl51v/2ghhk18BdUAkZDklwSX8hn/a TESE9Rms/XIhbCLReCaxevXXhF7Za0kyaGxiS+Y/J8v1XxGA3549F/YdnzkWmVO0Wkw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793187683; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: Reply-To:MIME-Version:Lines:X-Developer-Signature:X-Developer-Key: Content-Transfer-Encoding; bh=Lemixxq3LHEfKIjhr2R2mHFqR3cpyEJOVq4+iixKS5o=; b=Ocy7OkOGro8ZnJTzQYV6lGx6YMBYBMNyKL/Ij9Njs0jqJr48NKFmOYIfmDy66ygppQnV xOBCy9R8C1xqrP3Py4LQrXGa4qNUhild09dMGIOdXBgEM1u+9Gu5Fz7oh3SBL5hwL/CAZ 7rkynuO/PlUexuVZZesexx6iaofj/OM9FEIJuwvyHG1eOuhTzkh+FUk+I1Rqy3K7do7nc UMtn9rmRC2F7Fy3kSffmEz6UE/oJP9wP0EDEVaKhP2hgMC8IMU70CW3+XSWQSua6sZNbS FnW7dd6BN9l+zatIwovWYssAl7ZLBcISxKon492KUhUnXyvAjnz4b9ZqA13Mbpmw0Bg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b="dC4RaB/l"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 096DB606A31E for ; Wed, 28 Oct 2026 11:41:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=dC4RaB/l Received: by smtp.kernel.org (Postfix) with ESMTPSA id 452E11F01825; Wed, 28 Oct 2026 11:41:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793187682; bh=Lemixxq3LHEfKIjhr2R2mHFqR3cpyEJOVq4+iixKS5o=; h=From:To:Cc:Subject:Date:Reply-To; b=dC4RaB/lgUf9ObBH5uNLM45thlMjz+pHdKju8xyxgYHKbMhijn4tDumGsAnp2wB3B ernExKyoBsQ4QaTOVC3VWrSaNKUtH9IIEfphBbPl5pR78jpWFRD+fRvTi2PZ2u9dRI Y1zPCqHJoByTM4gEWg+G0e9Cp3nkUy4vxI0B7uY4= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-99192: net: bcmgenet: unshare the skb before writing the control block Date: Wed, 28 Oct 2026 11:36:19 +0100 Message-ID: <2026102812-CVE-2026-99192-e097@gregkh> X-Mailer: git-send-email 2.56.0 Reply-To: , X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3142; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=AIskmIS9nNOnDAcXYkUQHN9mJUI+FkWrFDmRChZdfcE=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkPzz9Y499lvrX6xIqOmu0F/2pCFlfv2ntS7MiDDxE7q 5aszHQs6IhlYRBkYpAVU2T5so3n6P6KQ4pehranYeawMoEMYeDiFICJCAowLNiizOx3sThj34v/ q/wll0g+UxQ+eIlhwcI1x3h/WQWcXXP+jXj3cdb2G2ZGrwA= 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: net: bcmgenet: unshare the skb before writing the control block bcmgenet stores first_cb, last_cb and bytes_sent in the skb control block and reads them back on completion to free the skb and credit BQL. ether_setup() leaves IFF_TX_SKB_SHARING set, so the stack can resubmit a shared skb that is still in the ring. The next transmit overwrites last_cb, so the earlier slots complete without crediting their bytes and BQL stalls the queue until the watchdog resets it. Unshare the skb before writing the control block. Reproduce with pktgen in clone_skb mode, which hands the driver the same skb while earlier copies are still in the ring: modprobe pktgen pg=/proc/net/pktgen echo "add_device eth0" > $pg/kpktgend_0 echo "dst_mac AA:BB:CC:DD:EE:FF" > $pg/eth0 echo "dst 192.0.2.1" > $pg/eth0 echo "clone_skb 8" > $pg/eth0 echo "count 0" > $pg/eth0 echo start > $pg/pgctrl & sleep 5 echo stop > $pg/pgctrl wait cat /sys/class/net/eth0/queues/tx-0/byte_queue_limits/inflight inflight stays nonzero on the now idle queue. clone_skb 0 leaves it at zero. The Linux kernel CVE team has assigned CVE-2026-99192 to this issue. Affected and fixed versions =========================== Issue introduced in 4.13 with commit f48bed16a756f5bc0244acd581f61968f7d7c2a4 and fixed in 6.18.59 with commit 40c04abcbc34e3afe338f41dae851ecbd72852ac Issue introduced in 4.13 with commit f48bed16a756f5bc0244acd581f61968f7d7c2a4 and fixed in 7.2.13 with commit 7939ad3b4db9eadf45a64f0524f38337a9494672 Issue introduced in 4.13 with commit f48bed16a756f5bc0244acd581f61968f7d7c2a4 and fixed in 7.3 with commit 89771ce4f8f67dcffae561b2ccac95c0f6e3aa01 Issue introduced in 3.16.50 with commit fb4ca2b4bc6712a6ad635df5b9b41131846589f9 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-2026-99192 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/ethernet/broadcom/genet/bcmgenet.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/40c04abcbc34e3afe338f41dae851ecbd72852ac https://git.kernel.org/stable/c/7939ad3b4db9eadf45a64f0524f38337a9494672 https://git.kernel.org/stable/c/89771ce4f8f67dcffae561b2ccac95c0f6e3aa01