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 --- arch/powerpc/sysdev/dcr-low.S | 44 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 arch/powerpc/sysdev/dcr-low.S (limited to 'arch/powerpc/sysdev/dcr-low.S') diff --git a/arch/powerpc/sysdev/dcr-low.S b/arch/powerpc/sysdev/dcr-low.S new file mode 100644 index 000000000..e8401b205 --- /dev/null +++ b/arch/powerpc/sysdev/dcr-low.S @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * "Indirect" DCR access + * + * Copyright (c) 2004 Eugene Surovegin + */ + +#include +#include +#include +#include + +#define DCR_ACCESS_PROLOG(table) \ + cmplwi cr0,r3,1024; \ + rlwinm r3,r3,4,18,27; \ + lis r5,table@h; \ + ori r5,r5,table@l; \ + add r3,r3,r5; \ + bge- 1f; \ + mtctr r3; \ + bctr; \ +1: trap; \ + EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,0; \ + blr + +_GLOBAL(__mfdcr) + DCR_ACCESS_PROLOG(__mfdcr_table) +EXPORT_SYMBOL(__mfdcr) + +_GLOBAL(__mtdcr) + DCR_ACCESS_PROLOG(__mtdcr_table) +EXPORT_SYMBOL(__mtdcr) + +__mfdcr_table: + mfdcr r3,0; blr +__mtdcr_table: + mtdcr 0,r4; blr + +dcr = 1 + .rept 1023 + mfdcr r3,dcr; blr + mtdcr dcr,r4; blr + dcr = dcr + 1 + .endr -- cgit v1.3.1