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>

1 files changed, 20 insertions, 0 deletions

diff --git a/net/ethtool/ts.h b/net/ethtool/ts.h
new file mode 100644
index 000000000..d901a879a
--- /dev/null
+++ b/net/ethtool/ts.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef _NET_ETHTOOL_TS_H
+#define _NET_ETHTOOL_TS_H
+
+#include "netlink.h"
+
+static const struct nla_policy
+ethnl_ts_hwtst_prov_policy[ETHTOOL_A_TS_HWTSTAMP_PROVIDER_MAX + 1] = {
+	[ETHTOOL_A_TS_HWTSTAMP_PROVIDER_INDEX] = { .type = NLA_U32 },
+	[ETHTOOL_A_TS_HWTSTAMP_PROVIDER_QUALIFIER] =
+		NLA_POLICY_MAX(NLA_U32, HWTSTAMP_PROVIDER_QUALIFIER_CNT - 1)
+};
+
+int ts_parse_hwtst_provider(const struct nlattr *nest,
+			    struct hwtstamp_provider_desc *hwprov_desc,
+			    struct netlink_ext_ack *extack,
+			    bool *mod);
+
+#endif /* _NET_ETHTOOL_TS_H */