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authorMuhammad Bilal <meatuni001@gmail.com>2026-07-28 17:54:55 +0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2026-09-01 12:15:16 +0200
commitff917923f4fb9c83717ba135ee47d7e4c1567bb7 (patch)
treec38fd8fcf58e1937b17fdbc6518b6f8b797fc15a /arch/powerpc/sysdev/dcr-low.S
downloadlinux-stable-ff917923f4fb9c83717ba135ee47d7e4c1567bb7.tar.gz
linux-stable-ff917923f4fb9c83717ba135ee47d7e4c1567bb7.zip
staging: rtl8723bs: fix OOB read in rtw_action_frame_parse()grafted
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 <meatuni001@gmail.com> Link: https://patch.msgid.link/20260728125456.32359-3-meatuni001@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/powerpc/sysdev/dcr-low.S')
-rw-r--r--arch/powerpc/sysdev/dcr-low.S44
1 files changed, 44 insertions, 0 deletions
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 <ebs@ebshome.net>
+ */
+
+#include <linux/export.h>
+#include <asm/ppc_asm.h>
+#include <asm/processor.h>
+#include <asm/bug.h>
+
+#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