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 --- include/net/mpls.h | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 include/net/mpls.h (limited to 'include/net/mpls.h') diff --git a/include/net/mpls.h b/include/net/mpls.h new file mode 100644 index 000000000..0bb7944e7 --- /dev/null +++ b/include/net/mpls.h @@ -0,0 +1,45 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2014 Nicira, Inc. + */ + +#ifndef _NET_MPLS_H +#define _NET_MPLS_H 1 + +#include +#include +#include + +#define MPLS_HLEN 4 + +struct mpls_shim_hdr { + __be32 label_stack_entry; +}; + +static inline bool eth_p_mpls(__be16 eth_type) +{ + return eth_type == htons(ETH_P_MPLS_UC) || + eth_type == htons(ETH_P_MPLS_MC); +} + +static inline struct mpls_shim_hdr *mpls_hdr(const struct sk_buff *skb) +{ + return (struct mpls_shim_hdr *)skb_network_header(skb); +} + +static inline struct mpls_shim_hdr mpls_entry_encode(u32 label, + unsigned int ttl, + unsigned int tc, + bool bos) +{ + struct mpls_shim_hdr result; + + result.label_stack_entry = + cpu_to_be32((label << MPLS_LS_LABEL_SHIFT) | + (tc << MPLS_LS_TC_SHIFT) | + (bos ? (1 << MPLS_LS_S_SHIFT) : 0) | + (ttl << MPLS_LS_TTL_SHIFT)); + return result; +} + +#endif -- cgit v1.3.1