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 D229343CEFA for ; Mon, 20 Jul 2026 16:28:36 +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=1784564919; cv=none; b=m64LwR2bIJiMX+QOU7gUOQ8guRggkkjvyOu5jpKs2f/VOnKGsc/JLdHEo+jONoFm3kp7pTrtwkvZJzey5Z1ELbj2B+D504Sm6ag4Z49Ua6VljCWPTxDHeZ5VVUnIDvgfYRzHSELe/vXmGCnMyfJ0fqIr+Y+MGC+Y4lSXFRSERjo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784564919; c=relaxed/simple; bh=hdCMrJ+Z8CjPFwLVDzAA6DFod7+T3c9ntOc9oxq4YRc=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=fmSwiBb+5R9C0vokXWjH6t08FpiVXL0xfhYVR5tKSuL7OpJ0Gwk+t5BRuyxfUDwAlZ1hxDZ2GKQS94Byk+J5oyUhllI4KhUqlUtyrCqbx5R/GOJGGpR0bztSxI4nZ7O+EVIhDGBeHChd/oIscDHsp4QyFrZf7ad0hIPQYL8Y6uY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=g5JhYr6u; 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="g5JhYr6u" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BC0191F000E9; Mon, 20 Jul 2026 16:28:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784564914; bh=bUUoptjf08tJoDlpZOh1wkOW3JtSbLYX+e9tYDrZ/4E=; h=From:To:Cc:Subject:Date:Reply-To; b=g5JhYr6u5s6ZX6nGUQ3qTJ8h+Uf8FrmH+nXvbhEx9BpWLDO2ooPvEXbmLlJSoFzyl o1ZA+YDOUPHaTVgqIqI8HSuFmsxvp3lI9j5zhJmKJTP9B2q5h7Wdp75Jv+hwlqVo// qBiwxaQzmc5OnzXOQy78tlWaEH5462yHVihrnyc0= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-64190: net: team: fix NULL pointer dereference in team_xmit during mode change Date: Mon, 20 Jul 2026 18:27:53 +0200 Message-ID: <2026072051-CVE-2026-64190-9dfc@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=3235; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=IHqUM4L+oegNvL/YSaVmslwaPuOtT20DMI61giE6vY4=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlxPu397DdLPdw+v6iU0q5eki+y+caFPvVsPf5tm3Pjj 07tfJfUEcvCIMjEICumyPJlG8/R/RWHFL0MbU/DzGFlAhnCwMUpABNJi2VYsO/Qiw+Kp/vm58k2 8TlXN2/NC78rwbDgspty66o4NYaoo4sZmzbfyjzzm3UhAA== 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: team: fix NULL pointer dereference in team_xmit during mode change __team_change_mode() clears team->ops with memset() before restoring safe dummy handlers via team_adjust_ops(). A concurrent team_xmit() running under RCU on another CPU can read team->ops.transmit during this window and call a NULL function pointer, crashing the kernel. The race requires a mode change (CAP_NET_ADMIN) concurrent with transmit on the team device. BUG: kernel NULL pointer dereference, address: 0000000000000000 Oops: 0010 [#1] SMP KASAN NOPTI RIP: 0010:0x0 Call Trace: team_xmit (drivers/net/team/team_core.c:1853) dev_hard_start_xmit (net/core/dev.c:3904) __dev_queue_xmit (net/core/dev.c:4871) packet_sendmsg (net/packet/af_packet.c:3109) __sys_sendto (net/socket.c:2265) The original code assumed that no ports means no traffic, so mode changes could freely memset()/memcpy() the ops. AF_PACKET with forced carrier breaks that assumption. Prevent the race instead of making it safe: replace memset()/memcpy() with per-field updates that never touch transmit or receive. Those two handlers are managed solely by team_adjust_ops(), which already installs dummies when tx_en_port_count == 0 (always true during mode change since no ports are present). WRITE_ONCE/READ_ONCE prevent store/load tearing on the handler pointers. synchronize_net() before exit_op() drains in-flight readers that may still reference old mode state from before port removal switched the handlers to dummies. The Linux kernel CVE team has assigned CVE-2026-64190 to this issue. Affected and fixed versions =========================== Issue introduced in 3.3 with commit 3d249d4ca7d0ed6629a135ea1ea21c72286c0d80 and fixed in 6.18.35 with commit 03e9405c518c4d61f28079492f252d6d4e2bac5c Issue introduced in 3.3 with commit 3d249d4ca7d0ed6629a135ea1ea21c72286c0d80 and fixed in 7.1 with commit 25fe708bbc59289d3d1ea4b126fbc1b460a072a5 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-2026-64190 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/team/team_core.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/03e9405c518c4d61f28079492f252d6d4e2bac5c https://git.kernel.org/stable/c/25fe708bbc59289d3d1ea4b126fbc1b460a072a5