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, 94 insertions, 0 deletions

diff --git a/fs/ext2/trace.h b/fs/ext2/trace.h
new file mode 100644
index 000000000..0922c0e6a
--- /dev/null
+++ b/fs/ext2/trace.h
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM ext2
+
+#if !defined(_EXT2_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _EXT2_TRACE_H
+
+#include <linux/tracepoint.h>
+
+DECLARE_EVENT_CLASS(ext2_dio_class,
+	TP_PROTO(struct kiocb *iocb, struct iov_iter *iter, ssize_t ret),
+	TP_ARGS(iocb, iter, ret),
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(u64,	ino)
+		__field(loff_t, isize)
+		__field(loff_t, pos)
+		__field(size_t,	count)
+		__field(int,	ki_flags)
+		__field(bool,	aio)
+		__field(ssize_t, ret)
+	),
+	TP_fast_assign(
+		__entry->dev = file_inode(iocb->ki_filp)->i_sb->s_dev;
+		__entry->ino = file_inode(iocb->ki_filp)->i_ino;
+		__entry->isize = file_inode(iocb->ki_filp)->i_size;
+		__entry->pos = iocb->ki_pos;
+		__entry->count = iov_iter_count(iter);
+		__entry->ki_flags = iocb->ki_flags;
+		__entry->aio = !is_sync_kiocb(iocb);
+		__entry->ret = ret;
+	),
+	TP_printk("dev %d:%d ino 0x%llx isize 0x%llx pos 0x%llx len %zu flags %s aio %d ret %zd",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  __entry->ino,
+		  __entry->isize,
+		  __entry->pos,
+		  __entry->count,
+		  __print_flags(__entry->ki_flags, "|", TRACE_IOCB_STRINGS),
+		  __entry->aio,
+		  __entry->ret)
+);
+
+#define DEFINE_DIO_RW_EVENT(name)					  \
+DEFINE_EVENT(ext2_dio_class, name,					  \
+	TP_PROTO(struct kiocb *iocb, struct iov_iter *iter, ssize_t ret), \
+	TP_ARGS(iocb, iter, ret))
+DEFINE_DIO_RW_EVENT(ext2_dio_write_begin);
+DEFINE_DIO_RW_EVENT(ext2_dio_write_end);
+DEFINE_DIO_RW_EVENT(ext2_dio_write_buff_end);
+DEFINE_DIO_RW_EVENT(ext2_dio_read_begin);
+DEFINE_DIO_RW_EVENT(ext2_dio_read_end);
+
+TRACE_EVENT(ext2_dio_write_endio,
+	TP_PROTO(struct kiocb *iocb, ssize_t size, int ret),
+	TP_ARGS(iocb, size, ret),
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(u64,	ino)
+		__field(loff_t, isize)
+		__field(loff_t, pos)
+		__field(ssize_t, size)
+		__field(int,	ki_flags)
+		__field(bool,	aio)
+		__field(int,	ret)
+	),
+	TP_fast_assign(
+		__entry->dev = file_inode(iocb->ki_filp)->i_sb->s_dev;
+		__entry->ino = file_inode(iocb->ki_filp)->i_ino;
+		__entry->isize = file_inode(iocb->ki_filp)->i_size;
+		__entry->pos = iocb->ki_pos;
+		__entry->size = size;
+		__entry->ki_flags = iocb->ki_flags;
+		__entry->aio = !is_sync_kiocb(iocb);
+		__entry->ret = ret;
+	),
+	TP_printk("dev %d:%d ino 0x%llx isize 0x%llx pos 0x%llx len %zd flags %s aio %d ret %d",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  __entry->ino,
+		  __entry->isize,
+		  __entry->pos,
+		  __entry->size,
+		  __print_flags(__entry->ki_flags, "|", TRACE_IOCB_STRINGS),
+		  __entry->aio,
+		  __entry->ret)
+);
+
+#endif /* _EXT2_TRACE_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE trace
+#include <trace/define_trace.h>