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/rtnh.h | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 include/net/rtnh.h (limited to 'include/net/rtnh.h') diff --git a/include/net/rtnh.h b/include/net/rtnh.h new file mode 100644 index 000000000..aa2cfc508 --- /dev/null +++ b/include/net/rtnh.h @@ -0,0 +1,34 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __NET_RTNH_H +#define __NET_RTNH_H + +#include +#include + +static inline int rtnh_ok(const struct rtnexthop *rtnh, int remaining) +{ + return remaining >= (int)sizeof(*rtnh) && + rtnh->rtnh_len >= sizeof(*rtnh) && + rtnh->rtnh_len <= remaining; +} + +static inline struct rtnexthop *rtnh_next(const struct rtnexthop *rtnh, + int *remaining) +{ + int totlen = NLA_ALIGN(rtnh->rtnh_len); + + *remaining -= totlen; + return (struct rtnexthop *) ((char *) rtnh + totlen); +} + +static inline struct nlattr *rtnh_attrs(const struct rtnexthop *rtnh) +{ + return (struct nlattr *) ((char *) rtnh + NLA_ALIGN(sizeof(*rtnh))); +} + +static inline int rtnh_attrlen(const struct rtnexthop *rtnh) +{ + return rtnh->rtnh_len - NLA_ALIGN(sizeof(*rtnh)); +} + +#endif -- cgit v1.3.1