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path: root/drivers/gpio/gpiolib.c
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Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r--drivers/gpio/gpiolib.c99
1 files changed, 86 insertions, 13 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index f0fc3a0d37c8..93ed0e00c578 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -21,6 +21,7 @@
 #include <linux/uaccess.h>
 #include <linux/compat.h>
 #include <linux/anon_inodes.h>
+#include <linux/file.h>
 #include <linux/kfifo.h>
 #include <linux/poll.h>
 #include <linux/timekeeping.h>
@@ -333,6 +334,13 @@ struct linehandle_state {
 	u32 numdescs;
 };
 
+#define GPIOHANDLE_REQUEST_VALID_FLAGS \
+	(GPIOHANDLE_REQUEST_INPUT | \
+	GPIOHANDLE_REQUEST_OUTPUT | \
+	GPIOHANDLE_REQUEST_ACTIVE_LOW | \
+	GPIOHANDLE_REQUEST_OPEN_DRAIN | \
+	GPIOHANDLE_REQUEST_OPEN_SOURCE)
+
 static long linehandle_ioctl(struct file *filep, unsigned int cmd,
 			     unsigned long arg)
 {
@@ -344,6 +352,8 @@ static long linehandle_ioctl(struct file *filep, unsigned int cmd,
 	if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
 		int val;
 
+		memset(&ghd, 0, sizeof(ghd));
+
 		/* TODO: check if descriptors are really input */
 		for (i = 0; i < lh->numdescs; i++) {
 			val = gpiod_get_value_cansleep(lh->descs[i]);
@@ -414,6 +424,7 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip)
 {
 	struct gpiohandle_request handlereq;
 	struct linehandle_state *lh;
+	struct file *file;
 	int fd, i, ret;
 
 	if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
@@ -444,6 +455,17 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip)
 		u32 lflags = handlereq.flags;
 		struct gpio_desc *desc;
 
+		if (offset >= gdev->ngpio) {
+			ret = -EINVAL;
+			goto out_free_descs;
+		}
+
+		/* Return an error if a unknown flag is set */
+		if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) {
+			ret = -EINVAL;
+			goto out_free_descs;
+		}
+
 		desc = &gdev->descs[offset];
 		ret = gpiod_request(desc, lh->label);
 		if (ret)
@@ -479,26 +501,41 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip)
 	i--;
 	lh->numdescs = handlereq.lines;
 
-	fd = anon_inode_getfd("gpio-linehandle",
-			      &linehandle_fileops,
-			      lh,
-			      O_RDONLY | O_CLOEXEC);
+	fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
 	if (fd < 0) {
 		ret = fd;
 		goto out_free_descs;
 	}
 
+	file = anon_inode_getfile("gpio-linehandle",
+				  &linehandle_fileops,
+				  lh,
+				  O_RDONLY | O_CLOEXEC);
+	if (IS_ERR(file)) {
+		ret = PTR_ERR(file);
+		goto out_put_unused_fd;
+	}
+
 	handlereq.fd = fd;
 	if (copy_to_user(ip, &handlereq, sizeof(handlereq))) {
-		ret = -EFAULT;
-		goto out_free_descs;
+		/*
+		 * fput() will trigger the release() callback, so do not go onto
+		 * the regular error cleanup path here.
+		 */
+		fput(file);
+		put_unused_fd(fd);
+		return -EFAULT;
 	}
 
+	fd_install(fd, file);
+
 	dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n",
 		lh->numdescs);
 
 	return 0;
 
+out_put_unused_fd:
+	put_unused_fd(fd);
 out_free_descs:
 	for (; i >= 0; i--)
 		gpiod_free(lh->descs[i]);
@@ -536,6 +573,10 @@ struct lineevent_state {
 	struct mutex read_lock;
 };
 
+#define GPIOEVENT_REQUEST_VALID_FLAGS \
+	(GPIOEVENT_REQUEST_RISING_EDGE | \
+	GPIOEVENT_REQUEST_FALLING_EDGE)
+
 static unsigned int lineevent_poll(struct file *filep,
 				   struct poll_table_struct *wait)
 {
@@ -623,6 +664,8 @@ static long lineevent_ioctl(struct file *filep, unsigned int cmd,
 	if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
 		int val;
 
+		memset(&ghd, 0, sizeof(ghd));
+
 		val = gpiod_get_value_cansleep(le->desc);
 		if (val < 0)
 			return val;
@@ -695,6 +738,7 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
 	struct gpioevent_request eventreq;
 	struct lineevent_state *le;
 	struct gpio_desc *desc;
+	struct file *file;
 	u32 offset;
 	u32 lflags;
 	u32 eflags;
@@ -726,6 +770,18 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
 	lflags = eventreq.handleflags;
 	eflags = eventreq.eventflags;
 
+	if (offset >= gdev->ngpio) {
+		ret = -EINVAL;
+		goto out_free_label;
+	}
+
+	/* Return an error if a unknown flag is set */
+	if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) ||
+	    (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS)) {
+		ret = -EINVAL;
+		goto out_free_label;
+	}
+
 	/* This is just wrong: we don't look for events on output lines */
 	if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
 		ret = -EINVAL;
@@ -777,23 +833,38 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
 	if (ret)
 		goto out_free_desc;
 
-	fd = anon_inode_getfd("gpio-event",
-			      &lineevent_fileops,
-			      le,
-			      O_RDONLY | O_CLOEXEC);
+	fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
 	if (fd < 0) {
 		ret = fd;
 		goto out_free_irq;
 	}
 
+	file = anon_inode_getfile("gpio-event",
+				  &lineevent_fileops,
+				  le,
+				  O_RDONLY | O_CLOEXEC);
+	if (IS_ERR(file)) {
+		ret = PTR_ERR(file);
+		goto out_put_unused_fd;
+	}
+
 	eventreq.fd = fd;
 	if (copy_to_user(ip, &eventreq, sizeof(eventreq))) {
-		ret = -EFAULT;
-		goto out_free_irq;
+		/*
+		 * fput() will trigger the release() callback, so do not go onto
+		 * the regular error cleanup path here.
+		 */
+		fput(file);
+		put_unused_fd(fd);
+		return -EFAULT;
 	}
 
+	fd_install(fd, file);
+
 	return 0;
 
+out_put_unused_fd:
+	put_unused_fd(fd);
 out_free_irq:
 	free_irq(le->irq, le);
 out_free_desc:
@@ -823,6 +894,8 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 	if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
 		struct gpiochip_info chipinfo;
 
+		memset(&chipinfo, 0, sizeof(chipinfo));
+
 		strncpy(chipinfo.name, dev_name(&gdev->dev),
 			sizeof(chipinfo.name));
 		chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
@@ -839,7 +912,7 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 
 		if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
 			return -EFAULT;
-		if (lineinfo.line_offset > gdev->ngpio)
+		if (lineinfo.line_offset >= gdev->ngpio)
 			return -EINVAL;
 
 		desc = &gdev->descs[lineinfo.line_offset];