1 files changed, 216 insertions, 27 deletions

diff --git a/net/wireless/debugfs.c b/net/wireless/debugfs.c
index 90d050036624..f9e7fff1ef25 100644
--- a/net/wireless/debugfs.c
+++ b/net/wireless/debugfs.c
@@ -1,12 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * cfg80211 debugfs
  *
  * Copyright 2009	Luis R. Rodriguez <lrodriguez@atheros.com>
  * Copyright 2007	Johannes Berg <johannes@sipsolutions.net>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * Copyright (C) 2023 Intel Corporation
  */
 
 #include <linux/slab.h>
@@ -17,7 +15,7 @@
 static ssize_t name## _read(struct file *file, char __user *userbuf,	\
 			    size_t count, loff_t *ppos)			\
 {									\
-	struct wiphy *wiphy= file->private_data;		\
+	struct wiphy *wiphy = file->private_data;			\
 	char buf[buflen];						\
 	int res;							\
 									\
@@ -29,17 +27,38 @@ static const struct file_operations name## _ops = {			\
 	.read = name## _read,						\
 	.open = simple_open,						\
 	.llseek = generic_file_llseek,					\
-};
+}
+
+#define DEBUGFS_RADIO_READONLY_FILE(name, buflen, fmt, value...)	\
+static ssize_t name## _read(struct file *file, char __user *userbuf,	\
+			    size_t count, loff_t *ppos)			\
+{									\
+	struct wiphy_radio_cfg *radio_cfg = file->private_data;		\
+	char buf[buflen];						\
+	int res;							\
+									\
+	res = scnprintf(buf, buflen, fmt "\n", ##value);		\
+	return simple_read_from_buffer(userbuf, count, ppos, buf, res);	\
+}									\
+									\
+static const struct file_operations name## _ops = {			\
+	.read = name## _read,						\
+	.open = simple_open,						\
+	.llseek = generic_file_llseek,					\
+}
 
 DEBUGFS_READONLY_FILE(rts_threshold, 20, "%d",
-		      wiphy->rts_threshold)
+		      wiphy->rts_threshold);
 DEBUGFS_READONLY_FILE(fragmentation_threshold, 20, "%d",
 		      wiphy->frag_threshold);
 DEBUGFS_READONLY_FILE(short_retry_limit, 20, "%d",
-		      wiphy->retry_short)
+		      wiphy->retry_short);
 DEBUGFS_READONLY_FILE(long_retry_limit, 20, "%d",
 		      wiphy->retry_long);
 
+DEBUGFS_RADIO_READONLY_FILE(radio_rts_threshold, 20, "%d",
+			    radio_cfg->rts_threshold);
+
 static int ht_print_chan(struct ieee80211_channel *chan,
 			 char *buf, int buf_size, int offset)
 {
@@ -47,17 +66,19 @@ static int ht_print_chan(struct ieee80211_channel *chan,
 		return 0;
 
 	if (chan->flags & IEEE80211_CHAN_DISABLED)
-		return snprintf(buf + offset,
-				buf_size - offset,
-				"%d Disabled\n",
-				chan->center_freq);
-
-	return snprintf(buf + offset,
-			buf_size - offset,
-			"%d HT40 %c%c\n",
-			chan->center_freq,
-			(chan->flags & IEEE80211_CHAN_NO_HT40MINUS) ? ' ' : '-',
-			(chan->flags & IEEE80211_CHAN_NO_HT40PLUS)  ? ' ' : '+');
+		return scnprintf(buf + offset,
+				 buf_size - offset,
+				 "%d Disabled\n",
+				 chan->center_freq);
+
+	return scnprintf(buf + offset,
+			 buf_size - offset,
+			 "%d HT40 %c%c\n",
+			 chan->center_freq,
+			 (chan->flags & IEEE80211_CHAN_NO_HT40MINUS) ?
+				' ' : '-',
+			 (chan->flags & IEEE80211_CHAN_NO_HT40PLUS) ?
+				' ' : '+');
 }
 
 static ssize_t ht40allow_map_read(struct file *file,
@@ -66,17 +87,16 @@ static ssize_t ht40allow_map_read(struct file *file,
 {
 	struct wiphy *wiphy = file->private_data;
 	char *buf;
-	unsigned int offset = 0, buf_size = PAGE_SIZE, i, r;
-	enum ieee80211_band band;
+	unsigned int offset = 0, buf_size = PAGE_SIZE, i;
+	enum nl80211_band band;
 	struct ieee80211_supported_band *sband;
+	ssize_t r;
 
 	buf = kzalloc(buf_size, GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;
 
-	rtnl_lock();
-
-	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
+	for (band = 0; band < NUM_NL80211_BANDS; band++) {
 		sband = wiphy->bands[band];
 		if (!sband)
 			continue;
@@ -85,8 +105,6 @@ static ssize_t ht40allow_map_read(struct file *file,
 						buf, buf_size, offset);
 	}
 
-	rtnl_unlock();
-
 	r = simple_read_from_buffer(user_buf, count, ppos, buf, offset);
 
 	kfree(buf);
@@ -101,15 +119,186 @@ static const struct file_operations ht40allow_map_ops = {
 };
 
 #define DEBUGFS_ADD(name)						\
-	debugfs_create_file(#name, S_IRUGO, phyd, &rdev->wiphy, &name## _ops);
+	debugfs_create_file(#name, 0444, phyd, &rdev->wiphy, &name## _ops)
+
+#define DEBUGFS_RADIO_ADD(name, radio_idx)				\
+	debugfs_create_file(#name, 0444, radiod,			\
+			    &rdev->wiphy.radio_cfg[radio_idx],		\
+			    &name## _ops)
 
 void cfg80211_debugfs_rdev_add(struct cfg80211_registered_device *rdev)
 {
 	struct dentry *phyd = rdev->wiphy.debugfsdir;
+	struct dentry *radiod;
+	u8 i;
 
 	DEBUGFS_ADD(rts_threshold);
 	DEBUGFS_ADD(fragmentation_threshold);
 	DEBUGFS_ADD(short_retry_limit);
 	DEBUGFS_ADD(long_retry_limit);
 	DEBUGFS_ADD(ht40allow_map);
+
+	for (i = 0; i < rdev->wiphy.n_radio; i++) {
+		radiod = rdev->wiphy.radio_cfg[i].radio_debugfsdir;
+		DEBUGFS_RADIO_ADD(radio_rts_threshold, i);
+	}
+}
+
+struct debugfs_read_work {
+	struct wiphy_work work;
+	ssize_t (*handler)(struct wiphy *wiphy,
+			   struct file *file,
+			   char *buf,
+			   size_t count,
+			   void *data);
+	struct wiphy *wiphy;
+	struct file *file;
+	char *buf;
+	size_t bufsize;
+	void *data;
+	ssize_t ret;
+	struct completion completion;
+};
+
+static void wiphy_locked_debugfs_read_work(struct wiphy *wiphy,
+					   struct wiphy_work *work)
+{
+	struct debugfs_read_work *w = container_of(work, typeof(*w), work);
+
+	w->ret = w->handler(w->wiphy, w->file, w->buf, w->bufsize, w->data);
+	complete(&w->completion);
+}
+
+static void wiphy_locked_debugfs_read_cancel(struct dentry *dentry,
+					     void *data)
+{
+	struct debugfs_read_work *w = data;
+
+	wiphy_work_cancel(w->wiphy, &w->work);
+	complete(&w->completion);
+}
+
+ssize_t wiphy_locked_debugfs_read(struct wiphy *wiphy, struct file *file,
+				  char *buf, size_t bufsize,
+				  char __user *userbuf, size_t count,
+				  loff_t *ppos,
+				  ssize_t (*handler)(struct wiphy *wiphy,
+						     struct file *file,
+						     char *buf,
+						     size_t bufsize,
+						     void *data),
+				  void *data)
+{
+	struct debugfs_read_work work = {
+		.handler = handler,
+		.wiphy = wiphy,
+		.file = file,
+		.buf = buf,
+		.bufsize = bufsize,
+		.data = data,
+		.ret = -ENODEV,
+		.completion = COMPLETION_INITIALIZER_ONSTACK(work.completion),
+	};
+	struct debugfs_cancellation cancellation = {
+		.cancel = wiphy_locked_debugfs_read_cancel,
+		.cancel_data = &work,
+	};
+
+	/* don't leak stack data or whatever */
+	memset(buf, 0, bufsize);
+
+	wiphy_work_init(&work.work, wiphy_locked_debugfs_read_work);
+	wiphy_work_queue(wiphy, &work.work);
+
+	debugfs_enter_cancellation(file, &cancellation);
+	wait_for_completion(&work.completion);
+	debugfs_leave_cancellation(file, &cancellation);
+
+	if (work.ret < 0)
+		return work.ret;
+
+	if (WARN_ON(work.ret > bufsize))
+		return -EINVAL;
+
+	return simple_read_from_buffer(userbuf, count, ppos, buf, work.ret);
+}
+EXPORT_SYMBOL_GPL(wiphy_locked_debugfs_read);
+
+struct debugfs_write_work {
+	struct wiphy_work work;
+	ssize_t (*handler)(struct wiphy *wiphy,
+			   struct file *file,
+			   char *buf,
+			   size_t count,
+			   void *data);
+	struct wiphy *wiphy;
+	struct file *file;
+	char *buf;
+	size_t count;
+	void *data;
+	ssize_t ret;
+	struct completion completion;
+};
+
+static void wiphy_locked_debugfs_write_work(struct wiphy *wiphy,
+					    struct wiphy_work *work)
+{
+	struct debugfs_write_work *w = container_of(work, typeof(*w), work);
+
+	w->ret = w->handler(w->wiphy, w->file, w->buf, w->count, w->data);
+	complete(&w->completion);
+}
+
+static void wiphy_locked_debugfs_write_cancel(struct dentry *dentry,
+					      void *data)
+{
+	struct debugfs_write_work *w = data;
+
+	wiphy_work_cancel(w->wiphy, &w->work);
+	complete(&w->completion);
+}
+
+ssize_t wiphy_locked_debugfs_write(struct wiphy *wiphy,
+				   struct file *file, char *buf, size_t bufsize,
+				   const char __user *userbuf, size_t count,
+				   ssize_t (*handler)(struct wiphy *wiphy,
+						      struct file *file,
+						      char *buf,
+						      size_t count,
+						      void *data),
+				   void *data)
+{
+	struct debugfs_write_work work = {
+		.handler = handler,
+		.wiphy = wiphy,
+		.file = file,
+		.buf = buf,
+		.count = count,
+		.data = data,
+		.ret = -ENODEV,
+		.completion = COMPLETION_INITIALIZER_ONSTACK(work.completion),
+	};
+	struct debugfs_cancellation cancellation = {
+		.cancel = wiphy_locked_debugfs_write_cancel,
+		.cancel_data = &work,
+	};
+
+	/* mostly used for strings so enforce NUL-termination for safety */
+	if (count >= bufsize)
+		return -EINVAL;
+
+	memset(buf, 0, bufsize);
+
+	if (copy_from_user(buf, userbuf, count))
+		return -EFAULT;
+
+	wiphy_work_init(&work.work, wiphy_locked_debugfs_write_work);
+	wiphy_work_queue(wiphy, &work.work);
+
+	debugfs_enter_cancellation(file, &cancellation);
+	wait_for_completion(&work.completion);
+	debugfs_leave_cancellation(file, &cancellation);
+
+	return work.ret;
 }
+EXPORT_SYMBOL_GPL(wiphy_locked_debugfs_write);