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/dsfield.h | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) create mode 100644 include/net/dsfield.h (limited to 'include/net/dsfield.h') diff --git a/include/net/dsfield.h b/include/net/dsfield.h new file mode 100644 index 000000000..a59a57ffc --- /dev/null +++ b/include/net/dsfield.h @@ -0,0 +1,53 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* include/net/dsfield.h - Manipulation of the Differentiated Services field */ + +/* Written 1998-2000 by Werner Almesberger, EPFL ICA */ + + +#ifndef __NET_DSFIELD_H +#define __NET_DSFIELD_H + +#include +#include +#include +#include + + +static inline __u8 ipv4_get_dsfield(const struct iphdr *iph) +{ + return iph->tos; +} + + +static inline __u8 ipv6_get_dsfield(const struct ipv6hdr *ipv6h) +{ + return ntohs(*(__force const __be16 *)ipv6h) >> 4; +} + + +static inline void ipv4_change_dsfield(struct iphdr *iph,__u8 mask, + __u8 value) +{ + __u32 check = ntohs((__force __be16)iph->check); + __u8 dsfield; + + dsfield = (iph->tos & mask) | value; + check += iph->tos; + if ((check+1) >> 16) check = (check+1) & 0xffff; + check -= dsfield; + check += check >> 16; /* adjust carry */ + iph->check = (__force __sum16)htons(check); + iph->tos = dsfield; +} + + +static inline void ipv6_change_dsfield(struct ipv6hdr *ipv6h,__u8 mask, + __u8 value) +{ + __be16 *p = (__force __be16 *)ipv6h; + + *p = (*p & htons((((u16)mask << 4) | 0xf00f))) | htons((u16)value << 4); +} + + +#endif -- cgit v1.3.1