From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f41.google.com (mail-wm1-f41.google.com [209.85.128.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 292C43AD52A for ; Thu, 13 Aug 2026 17:47:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.41 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786643264; cv=none; b=SeekqQPfth7tR7AkdMVKAKf3IypHJWn9XDOuEvEXkZ4hC/HyEMCYJfI8/dx7LxRguhaj2kISb7oabAiIUKirpQjzLPp7QDIhuaeXSGfxihTGNSYdpcEaAFJyr+IBA4ATsfWuBo1X4yjSvbN8cM9oA7JOsznKeVmuSBWY2QoCV9w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786643264; c=relaxed/simple; bh=q5930mDZa8nyXDAn+W2zn/rpNIQ+KxznOLcbAGh3aPM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=o7MkuTnHMGFMeQxrHh60KTLmDqeiWIeJ5VjbGE3XNdxyNlW4ccJ2ljaqHCpSnsqFixkzHL9RLu6NPQ7GwbQ5Rdi3buw8QfGCbgTGswj0cjp0Dfbw5sihco/hXOkLP8hR6POK1bgEpvIIF5lGdqsGF866Pf2XHiFJQMIOOcM7Ayo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=Z3t9CcOw; arc=none smtp.client-ip=209.85.128.41 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Z3t9CcOw" Received: by mail-wm1-f41.google.com with SMTP id 5b1f17b1804b1-4953e04ef16so1746975e9.2 for ; Thu, 13 Aug 2026 10:47:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1786643255; x=1787248055; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to:content-type; bh=c7wvD5wo2/av6+IbmyK7GMULA2iVsXLMzj4pik6CuA8=; b=Z3t9CcOwAncqE7QhT4dlnAP7AaOzRcPET7QKI/nHHfHHWkuS+VeRwIYoBS9ud9oI/D BkuVYOgvYULyONTTMkD2amDWLQTwB6POfC8JkqKNVsZqb0FDqJSJT20243uASOLHvfye YHMJIsbLXzwme/A7C1UuQzs8HLLDLM8PUQchadkeLPjx4Vjs8vKbJ4J4Qa4fJ/OAJzkN RUy61alhxpdGSqUTGPjMU/d2M5MXBtALvWfbNFHRMKRunn8aFIyxw8xDEB31BpavXIzz Rr3M1wmKqpxi9rRQ6D7xzx+21sJaSTi9i3VHd4mFAT+69uMC2++NnNEXwncSWqCK6oqp CMzg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1786643255; x=1787248055; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=c7wvD5wo2/av6+IbmyK7GMULA2iVsXLMzj4pik6CuA8=; b=T7boTIjwCsYledqiTskaNUC7BYP5a1KRrLHgmFsfzR0kPG+oOfIecUeYKmH6a/NJAz NlCuFF7ES9J5+CuvVey3Ldx0FjwTy1YsYf1eBDxsFfgczEMKvMTGwCg2fkPa1nsgQ86D 9T7xs5y7LlRegV3xVNqfoW5+qA3UzZ8yDC4yhfQ3wrf39b4r4Pgnf3GHg9u88CyTK0Ht oHbWwg8XM/fYGfScs4iMT8FOXNxkuuR2vVYoDp0LN7QsC9OAddktuqoxMGwKMRywKEKI eFYAyNXlaMhOdBkUY97QnzN8/xMFeRE9KnLo5Bio/SQ9RyF9gd+GQC4ibsOtSN4T6Qqu bdCw== X-Gm-Message-State: AOJu0Yzq/8SNYQ33jiiI9eyACCs0GgrMm11Q0v9gsKc8kUPRHlyD+D1F fzytoRfVN0Np9HHpPiQGaO6/GaNN+qI7YuizhC/qF0eI1aJ58JoPm4l+qN/DGA== X-Gm-Gg: AR+sD13zzveF9/83Y13Sr8PI9yzI59xbddaYQ2pyY5bstL+m8M+E9dYVQwM3CHoSvyz 9alLP/mF4NQs/ztpgGouQEgkOfgpdceK3Ev/rCyra08SIPSL6PNJEnceU+m7xD4+QQrnShRXLlZ FNKqmgMXMnYpeV7mJyt6hXNajFFAGkfN0ZKRvROkmefIoccyLp/KCbTnzHvju98XlYakOGIg0LD C4Rj5cA76D3moQPHXCzU9nHjLAkYcBS2Ql+eCH1l4hqOTw20qyIXD3M6sfvcdxoS7Z+t8uQ5CVH 8W1Y7jLw7W9FVlBZgN2cYRngwV48ODrlAvNW2cZhIUxy0p0SUh9OCwvr9+HGKFyGGqU3zuKHLjK zgaxYTlphD4GQEPo3xt7Gf58VQ9vEB6PUsl6r1DnVn1RCALPvUyLNBQvxxTm75c907we4RP4Ab7 0g2XNd3CXc+m7bA6rp5M8GgxerCQ/R9ZDr+WwcW2WDAm3KyvXm3+EdYPrEl29/370koG8= X-Received: by 2002:a05:600c:34cf:b0:499:48bb:417e with SMTP id 5b1f17b1804b1-49987929750mr3080675e9.2.1786643254529; Thu, 13 Aug 2026 10:47:34 -0700 (PDT) Received: from SurHub.localdomain ([102.218.51.180]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-49981b62437sm81694175e9.12.2026.08.13.10.47.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 13 Aug 2026 10:47:34 -0700 (PDT) From: Abdifatah Suruur To: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org, quic_subashab@quicinc.com, quic_stranche@quicinc.com, doruk@0sec.ai, Abdifatah Suruur Subject: [PATCH net] net: qualcomm: rmnet: require CAP_NET_ADMIN in the real device netns for changelink Date: Thu, 13 Aug 2026 20:47:27 +0300 Message-ID: <20260813174727.14857-1-suruurism@gmail.com> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit A changelink() on an rmnet device mutates the rmnet port state attached to the real device (endpoint mux table, port->data_format and, via rmnet_vnd_update_dev_mtu(), the real device MTU). The real device may live in a different netns than the rmnet device (rmnet_newlink() resolves it in link_net), but the rtnl path only checks CAP_NET_ADMIN against dev_net(dev). A caller privileged only in the rmnet device's netns can therefore rewrite the shared cellular data-path state owned by another netns. Gate rmnet_changelink() with rtnl_dev_link_net_capable(), matching the "require CAP_NET_ADMIN in the device netns for changelink" series (vxlan/geneve, CVE-2026-68432). Fixes: 2abb5792387e ("net: qualcomm: rmnet: Allow configuration updates to existing devices") Reported-by: Abdifatah Suruur Cc: stable@vger.kernel.org Signed-off-by: Abdifatah Suruur --- --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c @@ -312,6 +312,14 @@ if (!rmnet_is_real_dev_registered(real_dev)) return -ENODEV; + /* + * The rtnl path only checks CAP_NET_ADMIN against dev_net(dev), + * but the port state mutated below is attached to real_dev, which + * may live in a different netns. + */ + if (!rtnl_dev_link_net_capable(dev, dev_net(real_dev))) + return -EPERM; + port = rmnet_get_port_rtnl(real_dev); if (data[IFLA_RMNET_MUX_ID]) {