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, 59 insertions, 0 deletions

diff --git a/include/scsi/scsi_eh.h b/include/scsi/scsi_eh.h
new file mode 100644
index 000000000..15679be90
--- /dev/null
+++ b/include/scsi/scsi_eh.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _SCSI_SCSI_EH_H
+#define _SCSI_SCSI_EH_H
+
+#include <linux/scatterlist.h>
+
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_common.h>
+struct scsi_device;
+struct Scsi_Host;
+
+extern void scsi_eh_finish_cmd(struct scsi_cmnd *scmd,
+			       struct list_head *done_q);
+extern void scsi_eh_flush_done_q(struct list_head *done_q);
+extern void scsi_report_bus_reset(struct Scsi_Host *, int);
+extern void scsi_report_device_reset(struct Scsi_Host *, int, int);
+extern int scsi_block_when_processing_errors(struct scsi_device *);
+extern bool scsi_command_normalize_sense(const struct scsi_cmnd *cmd,
+					 struct scsi_sense_hdr *sshdr);
+extern enum scsi_disposition scsi_check_sense(struct scsi_cmnd *);
+
+static inline bool scsi_sense_is_deferred(const struct scsi_sense_hdr *sshdr)
+{
+	return ((sshdr->response_code >= 0x70) && (sshdr->response_code & 1));
+}
+
+extern bool scsi_get_sense_info_fld(const u8 *sense_buffer, int sb_len,
+				    u64 *info_out);
+
+extern int scsi_ioctl_reset(struct scsi_device *, int __user *);
+
+struct scsi_eh_save {
+	/* saved state */
+	int result;
+	unsigned int resid_len;
+	int eh_eflags;
+	enum dma_data_direction data_direction;
+	unsigned underflow;
+	unsigned char cmd_len;
+	unsigned char prot_op;
+	unsigned char cmnd[32];
+	struct scsi_data_buffer sdb;
+	struct scatterlist sense_sgl;
+
+	/* struct request fields */
+#ifdef CONFIG_BLK_INLINE_ENCRYPTION
+	struct bio_crypt_ctx *rq_crypt_ctx;
+	struct blk_crypto_keyslot *rq_crypt_keyslot;
+#endif
+};
+
+extern void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd,
+		struct scsi_eh_save *ses, unsigned char *cmnd,
+		int cmnd_size, unsigned sense_bytes);
+
+extern void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd,
+		struct scsi_eh_save *ses);
+
+#endif /* _SCSI_SCSI_EH_H */