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, 51 insertions, 0 deletions

diff --git a/rust/helpers/dma.c b/rust/helpers/dma.c
new file mode 100644
index 000000000..9fbeb507b
--- /dev/null
+++ b/rust/helpers/dma.c
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/dma-mapping.h>
+
+__rust_helper void *rust_helper_dma_alloc_attrs(struct device *dev, size_t size,
+						dma_addr_t *dma_handle,
+						gfp_t flag, unsigned long attrs)
+{
+	return dma_alloc_attrs(dev, size, dma_handle, flag, attrs);
+}
+
+__rust_helper void rust_helper_dma_free_attrs(struct device *dev, size_t size,
+					      void *cpu_addr,
+					      dma_addr_t dma_handle,
+					      unsigned long attrs)
+{
+	dma_free_attrs(dev, size, cpu_addr, dma_handle, attrs);
+}
+
+__rust_helper int rust_helper_dma_set_mask_and_coherent(struct device *dev,
+							u64 mask)
+{
+	return dma_set_mask_and_coherent(dev, mask);
+}
+
+__rust_helper int rust_helper_dma_set_mask(struct device *dev, u64 mask)
+{
+	return dma_set_mask(dev, mask);
+}
+
+__rust_helper int rust_helper_dma_set_coherent_mask(struct device *dev, u64 mask)
+{
+	return dma_set_coherent_mask(dev, mask);
+}
+
+__rust_helper int rust_helper_dma_map_sgtable(struct device *dev, struct sg_table *sgt,
+					      enum dma_data_direction dir, unsigned long attrs)
+{
+	return dma_map_sgtable(dev, sgt, dir, attrs);
+}
+
+__rust_helper size_t rust_helper_dma_max_mapping_size(struct device *dev)
+{
+	return dma_max_mapping_size(dev);
+}
+
+__rust_helper void rust_helper_dma_set_max_seg_size(struct device *dev,
+						    unsigned int size)
+{
+	dma_set_max_seg_size(dev, size);
+}