Commit 2db66876 authored by Dmitry Torokhov's avatar Dmitry Torokhov
Browse files

Input: limit attributes' output to PAGE_SIZE 



sysfs can't handle more than PAGE_SIZE data coming from attributes'
show() methods; make sure we respect this limit.

Signed-off-by: default avatarDmitry Torokhov <dtor@mail.ru>
parent 95d465fd

drivers/input/input.c

+24 −12
Original line number Diff line number Diff line
@@ -316,7 +316,8 @@ static struct input_device_id *input_match_device(struct input_device_id *id, st 
	return NULL;

}



static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap, int max)

static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,

			      int max, int add_cr)

{

	int i;

	int len = 0;
@@ -328,6 +329,10 @@ static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap, in 
	for (; i >= 0; i--)

		len += snprintf(buf + len, max(buf_size - len, 0),

				"%lx%s", bitmap[i], i > 0 ? " " : "");



	if (add_cr)

		len += snprintf(buf + len, max(buf_size - len, 0), "\n");



	return len;

}
@@ -356,8 +361,7 @@ static unsigned int input_devices_poll(struct file *file, poll_table *wait) 
	do {								\

		len += sprintf(buf + len, "B: %s=", #ev);		\

		len += input_print_bitmap(buf + len, INT_MAX,		\

					dev->bm##bit, ev##_MAX);	\

		len += sprintf(buf + len, "\n");			\

					dev->bm##bit, ev##_MAX, 1);	\

	} while (0)



#define TEST_AND_SPRINTF_BIT(ev, bm)					\
@@ -517,7 +521,8 @@ static ssize_t input_dev_show_##name(struct class_device *dev, char *buf) \ 
	if (retval)								\

		return retval;							\

										\

	retval = sprintf(buf, "%s\n", input_dev->name ? input_dev->name : "");	\

	retval = scnprintf(buf, PAGE_SIZE,					\

			   "%s\n", input_dev->name ? input_dev->name : "");	\

										\

	mutex_unlock(&input_dev->mutex);					\

										\
@@ -541,7 +546,8 @@ static int print_modalias_bits(char *buf, int size, char prefix, unsigned long * 
	return len;

}



static int print_modalias(char *buf, int size, struct input_dev *id)

static int input_print_modalias(char *buf, int size, struct input_dev *id,

				int add_cr)

{

	int len;
@@ -569,6 +575,10 @@ static int print_modalias(char *buf, int size, struct input_dev *id) 
				   0, FF_MAX);

	len += print_modalias_bits(buf + len, size - len, 'w', id->swbit,

				   0, SW_MAX);



	if (add_cr)

		len += snprintf(buf + len, size - len, "\n");



	return len;

}
@@ -577,9 +587,9 @@ static ssize_t input_dev_show_modalias(struct class_device *dev, char *buf) 
	struct input_dev *id = to_input_dev(dev);

	ssize_t len;



	len = print_modalias(buf, PAGE_SIZE, id);

	len += snprintf(buf + len, PAGE_SIZE-len, "\n");

	return len;

	len = input_print_modalias(buf, PAGE_SIZE, id, 1);



	return max_t(int, len, PAGE_SIZE);

}

static CLASS_DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
@@ -599,7 +609,7 @@ static struct attribute_group input_dev_attr_group = { 
static ssize_t input_dev_show_id_##name(struct class_device *dev, char *buf)	\

{										\

	struct input_dev *input_dev = to_input_dev(dev);			\

	return sprintf(buf, "%04x\n", input_dev->id.name);			\

	return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name);		\

}										\

static CLASS_DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL);
@@ -625,7 +635,9 @@ static struct attribute_group input_dev_id_attr_group = { 
static ssize_t input_dev_show_cap_##bm(struct class_device *dev, char *buf)	\

{										\

	struct input_dev *input_dev = to_input_dev(dev);			\

	return input_print_bitmap(buf, PAGE_SIZE, input_dev->bm##bit, ev##_MAX);\

	int len = input_print_bitmap(buf, PAGE_SIZE,				\

				     input_dev->bm##bit, ev##_MAX, 1);		\

	return min_t(int, len, PAGE_SIZE);					\

}										\

static CLASS_DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL);
@@ -684,7 +696,7 @@ static int input_add_uevent_bm_var(char **envp, int num_envp, int *cur_index, 


	*cur_len += input_print_bitmap(buffer + *cur_len,

					max(buffer_size - *cur_len, 0),

					bitmap, max) + 1;

					bitmap, max, 0) + 1;

	if (*cur_len > buffer_size)

		return -ENOMEM;
@@ -747,7 +759,7 @@ static int input_dev_uevent(struct class_device *cdev, char **envp, 


	envp[i++] = buffer + len;

	len += snprintf(buffer + len, buffer_size - len, "MODALIAS=");

	len += print_modalias(buffer + len, buffer_size - len, dev) + 1;

	len += input_print_modalias(buffer + len, buffer_size - len, dev, 0) + 1;



	envp[i] = NULL;

	return 0;