From ff917923f4fb9c83717ba135ee47d7e4c1567bb7 Mon Sep 17 00:00:00 2001 From: Muhammad Bilal Date: Tue, 28 Jul 2026 17:54:55 +0500 Subject: staging: rtl8723bs: fix OOB read in rtw_action_frame_parse() rtw_action_frame_parse() takes a frame_len parameter but never actually checks it before indexing into the frame body: const u8 *frame_body = frame + sizeof(struct ieee80211_hdr_3addr); ... c = frame_body[0]; ... a = frame_body[1]; frame_body already points 24 bytes (sizeof(struct ieee80211_hdr_3addr)) into frame, so reading frame_body[0] and frame_body[1] requires frame_len >= 26. A management action frame shorter than that (e.g. exactly 24 bytes, the minimum a malicious peer can send) causes a 1-2 byte out-of-bounds read. This is reachable from rtw_cfg80211_monitor_if_xmit_entry() and cfg80211_rtw_mgmt_tx() in ioctl_cfg80211.c, both of which pass attacker/user-influenced frame buffers and lengths straight through. Add the missing length check before frame_body is dereferenced. Fixes: 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver") Cc: stable@vger.kernel.org Signed-off-by: Muhammad Bilal Link: https://patch.msgid.link/20260728125456.32359-3-meatuni001@gmail.com Signed-off-by: Greg Kroah-Hartman --- net/devres.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+) create mode 100644 net/devres.c (limited to 'net/devres.c') diff --git a/net/devres.c b/net/devres.c new file mode 100644 index 000000000..5ccf6ca31 --- /dev/null +++ b/net/devres.c @@ -0,0 +1,95 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * This file contains all networking devres helpers. + */ + +#include +#include +#include + +struct net_device_devres { + struct net_device *ndev; +}; + +static void devm_free_netdev(struct device *dev, void *this) +{ + struct net_device_devres *res = this; + + free_netdev(res->ndev); +} + +struct net_device *devm_alloc_etherdev_mqs(struct device *dev, int sizeof_priv, + unsigned int txqs, unsigned int rxqs) +{ + struct net_device_devres *dr; + + dr = devres_alloc(devm_free_netdev, sizeof(*dr), GFP_KERNEL); + if (!dr) + return NULL; + + dr->ndev = alloc_etherdev_mqs(sizeof_priv, txqs, rxqs); + if (!dr->ndev) { + devres_free(dr); + return NULL; + } + + devres_add(dev, dr); + + return dr->ndev; +} +EXPORT_SYMBOL(devm_alloc_etherdev_mqs); + +static void devm_unregister_netdev(struct device *dev, void *this) +{ + struct net_device_devres *res = this; + + unregister_netdev(res->ndev); +} + +static int netdev_devres_match(struct device *dev, void *this, void *match_data) +{ + struct net_device_devres *res = this; + struct net_device *ndev = match_data; + + return ndev == res->ndev; +} + +/** + * devm_register_netdev - resource managed variant of register_netdev() + * @dev: managing device for this netdev - usually the parent device + * @ndev: device to register + * + * This is a devres variant of register_netdev() for which the unregister + * function will be called automatically when the managing device is + * detached. Note: the net_device used must also be resource managed by + * the same struct device. + */ +int devm_register_netdev(struct device *dev, struct net_device *ndev) +{ + struct net_device_devres *dr; + int ret; + + /* struct net_device must itself be managed. For now a managed netdev + * can only be allocated by devm_alloc_etherdev_mqs() so the check is + * straightforward. + */ + if (WARN_ON(!devres_find(dev, devm_free_netdev, + netdev_devres_match, ndev))) + return -EINVAL; + + dr = devres_alloc(devm_unregister_netdev, sizeof(*dr), GFP_KERNEL); + if (!dr) + return -ENOMEM; + + ret = register_netdev(ndev); + if (ret) { + devres_free(dr); + return ret; + } + + dr->ndev = ndev; + devres_add(ndev->dev.parent, dr); + + return 0; +} +EXPORT_SYMBOL(devm_register_netdev); -- cgit v1.3.1