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, 53 insertions, 0 deletions

diff --git a/rust/helpers/spinlock.c b/rust/helpers/spinlock.c
new file mode 100644
index 000000000..d53400c15
--- /dev/null
+++ b/rust/helpers/spinlock.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/spinlock.h>
+
+__rust_helper void rust_helper___spin_lock_init(spinlock_t *lock,
+						const char *name,
+						struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_SPINLOCK
+# if defined(CONFIG_PREEMPT_RT)
+	__spin_lock_init(lock, name, key, false);
+# else /*!CONFIG_PREEMPT_RT */
+	__raw_spin_lock_init(spinlock_check(lock), name, key, LD_WAIT_CONFIG);
+# endif /* CONFIG_PREEMPT_RT */
+#else /* !CONFIG_DEBUG_SPINLOCK */
+	spin_lock_init(lock);
+#endif /* CONFIG_DEBUG_SPINLOCK */
+}
+
+__rust_helper void rust_helper_spin_lock(spinlock_t *lock)
+{
+	spin_lock(lock);
+}
+
+__rust_helper void rust_helper_spin_unlock(spinlock_t *lock)
+{
+	spin_unlock(lock);
+}
+
+__rust_helper int rust_helper_spin_trylock(spinlock_t *lock)
+{
+	return spin_trylock(lock);
+}
+
+__rust_helper void rust_helper_spin_assert_is_held(spinlock_t *lock)
+{
+	lockdep_assert_held(lock);
+}
+
+__rust_helper void rust_helper_spin_lock_irq_disable(spinlock_t *lock)
+{
+	spin_lock_irq_disable(lock);
+}
+
+__rust_helper void rust_helper_spin_unlock_irq_enable(spinlock_t *lock)
+{
+	spin_unlock_irq_enable(lock);
+}
+
+__rust_helper int rust_helper_spin_trylock_irq_disable(spinlock_t *lock)
+{
+	return spin_trylock_irq_disable(lock);
+}