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, 80 insertions, 0 deletions

diff --git a/include/scsi/scsi_dbg.h b/include/scsi/scsi_dbg.h
new file mode 100644
index 000000000..efcdc7853
--- /dev/null
+++ b/include/scsi/scsi_dbg.h
@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _SCSI_SCSI_DBG_H
+#define _SCSI_SCSI_DBG_H
+
+struct scsi_cmnd;
+struct scsi_device;
+struct scsi_sense_hdr;
+
+extern void scsi_print_command(struct scsi_cmnd *);
+extern size_t __scsi_format_command(char *, size_t,
+				   const unsigned char *, size_t);
+extern void scsi_print_sense_hdr(const struct scsi_device *, const char *,
+				 const struct scsi_sense_hdr *);
+extern void scsi_print_sense(struct scsi_cmnd *);
+extern void __scsi_print_sense(const struct scsi_device *, const char *name,
+			       const unsigned char *sense_buffer,
+			       int sense_len);
+extern void scsi_print_result(struct scsi_cmnd *, const char *, int);
+
+#ifdef CONFIG_SCSI_CONSTANTS
+extern bool scsi_opcode_sa_name(int, int, const char **, const char **);
+extern const char *scsi_sense_key_string(unsigned char);
+extern const char *scsi_extd_sense_format(unsigned char, unsigned char,
+					  const char **);
+extern const char *scsi_mlreturn_string(int);
+extern const char *scsi_hostbyte_string(int);
+#else
+static inline bool
+scsi_opcode_sa_name(int cmd, int sa,
+		    const char **cdb_name, const char **sa_name)
+{
+	*cdb_name = NULL;
+	switch (cmd) {
+	case VARIABLE_LENGTH_CMD:
+	case MAINTENANCE_IN:
+	case MAINTENANCE_OUT:
+	case PERSISTENT_RESERVE_IN:
+	case PERSISTENT_RESERVE_OUT:
+	case SERVICE_ACTION_IN_12:
+	case SERVICE_ACTION_OUT_12:
+	case SERVICE_ACTION_BIDIRECTIONAL:
+	case SERVICE_ACTION_IN_16:
+	case SERVICE_ACTION_OUT_16:
+	case EXTENDED_COPY:
+	case RECEIVE_COPY_RESULTS:
+		*sa_name = NULL;
+		return true;
+	default:
+		return false;
+	}
+}
+
+static inline const char *
+scsi_sense_key_string(unsigned char key)
+{
+	return NULL;
+}
+
+static inline const char *
+scsi_extd_sense_format(unsigned char asc, unsigned char ascq, const char **fmt)
+{
+	*fmt = NULL;
+	return NULL;
+}
+
+static inline const char *
+scsi_mlreturn_string(int result)
+{
+	return NULL;
+}
+
+static inline const char *
+scsi_hostbyte_string(int result)
+{
+	return NULL;
+}
+
+#endif
+
+#endif /* _SCSI_SCSI_DBG_H */