Commit e639ba48 authored Mar 15, 2010 by Bruno Prémont Committed by Jiri Kosina Mar 16, 2010

HID: avoid '\0' in hid debugfs events file



When dumping /sys/kernel/debug/hid/$device/events '\0' characters show up
(invisible if cat to console but shown by less or while looking at a dump
 file).  These are due to hid_debug_event() adding strlen()+1 bytes to the ring
buffer (e.g. including the trailing '\0').  Any roll-over causes a '\0' as well
as hid_debug_event() handles the ring buffers with HID_DEBUG_BUFSIZE-1 size
while hid_debug_events_read() handles it with full HID_DEBUG_BUFSIZE size.

Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

parent 3ee8f0a2

drivers/hid/hid-debug.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -564,10 +564,10 @@ void hid_debug_event(struct hid_device hdev, char buf)
		struct hid_debug_list *list;

		list_for_each_entry(list, &hdev->debug_list, node) {
		for (i = 0; i <= strlen(buf); i++)
		list->hid_debug_buf[(list->tail + i) % (HID_DEBUG_BUFSIZE - 1)] =
		for (i = 0; i < strlen(buf); i++)
		list->hid_debug_buf[(list->tail + i) % HID_DEBUG_BUFSIZE] =
		buf[i];
		list->tail = (list->tail + i) % (HID_DEBUG_BUFSIZE - 1);
		list->tail = (list->tail + i) % HID_DEBUG_BUFSIZE;
		}
		}
		EXPORT_SYMBOL_GPL(hid_debug_event);

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