[PATCH] USB: update usbmon, fix glued lines
This update contains one bug fix: some lines can come out truncated,
because of the safety cutoff. This happened because I forgot to update
the size when status packets began to be printed.
The rest is:
- Comments updates
- Allow snooping with pkmap on x86_64, which is cache-coherent
- Enlarge event buffers (certainly we can have a couple of pages)
- Add event counter
First touch upon usbmon for 2.6.18.
Signed-off-by: Pete Zaitcev <zaitcev@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/mon/mon_dma.c b/drivers/usb/mon/mon_dma.c
index 0a1367b..ddcfc01 100644
--- a/drivers/usb/mon/mon_dma.c
+++ b/drivers/usb/mon/mon_dma.c
@@ -13,7 +13,10 @@
#include <linux/usb.h> /* Only needed for declarations in usb_mon.h */
#include "usb_mon.h"
-#ifdef __i386__ /* CONFIG_ARCH_I386 does not exit */
+/*
+ * PC-compatibles, are, fortunately, sufficiently cache-coherent for this.
+ */
+#if defined(__i386__) || defined(__x86_64__) /* CONFIG_ARCH_I386 doesn't exit */
#define MON_HAS_UNMAP 1
#define phys_to_page(phys) pfn_to_page((phys) >> PAGE_SHIFT)
diff --git a/drivers/usb/mon/mon_main.c b/drivers/usb/mon/mon_main.c
index 6ecc273..86db92b 100644
--- a/drivers/usb/mon/mon_main.c
+++ b/drivers/usb/mon/mon_main.c
@@ -97,6 +97,7 @@
if (mbus->nreaders == 0)
goto out_locked;
+ mbus->cnt_events++;
list_for_each (pos, &mbus->r_list) {
r = list_entry(pos, struct mon_reader, r_link);
r->rnf_submit(r->r_data, urb);
@@ -152,6 +153,7 @@
}
spin_lock_irqsave(&mbus->lock, flags);
+ mbus->cnt_events++;
list_for_each (pos, &mbus->r_list) {
r = list_entry(pos, struct mon_reader, r_link);
r->rnf_complete(r->r_data, urb);
@@ -163,7 +165,6 @@
/*
* Stop monitoring.
- * Obviously this must be well locked, so no need to play with mb's.
*/
static void mon_stop(struct mon_bus *mbus)
{
diff --git a/drivers/usb/mon/mon_stat.c b/drivers/usb/mon/mon_stat.c
index 6e4b165..1fe01d9 100644
--- a/drivers/usb/mon/mon_stat.c
+++ b/drivers/usb/mon/mon_stat.c
@@ -31,8 +31,8 @@
mbus = inode->u.generic_ip;
sp->slen = snprintf(sp->str, STAT_BUF_SIZE,
- "nreaders %d text_lost %u\n",
- mbus->nreaders, mbus->cnt_text_lost);
+ "nreaders %d events %u text_lost %u\n",
+ mbus->nreaders, mbus->cnt_events, mbus->cnt_text_lost);
file->private_data = sp;
return 0;
diff --git a/drivers/usb/mon/mon_text.c b/drivers/usb/mon/mon_text.c
index ac043ec..9f9236b 100644
--- a/drivers/usb/mon/mon_text.c
+++ b/drivers/usb/mon/mon_text.c
@@ -26,10 +26,13 @@
/*
* This limit exists to prevent OOMs when the user process stops reading.
+ * If usbmon were available to unprivileged processes, it might be open
+ * to a local DoS. But we have to keep to root in order to prevent
+ * password sniffing from HID devices.
*/
-#define EVENT_MAX 25
+#define EVENT_MAX (2*PAGE_SIZE / sizeof(struct mon_event_text))
-#define PRINTF_DFL 130
+#define PRINTF_DFL 160
struct mon_event_text {
struct list_head e_link;
@@ -111,7 +114,7 @@
* number of corner cases, but it seems that the following is
* more or less safe.
*
- * We do not even try to look transfer_buffer, because it can
+ * We do not even try to look at transfer_buffer, because it can
* contain non-NULL garbage in case the upper level promised to
* set DMA for the HCD.
*/
diff --git a/drivers/usb/mon/usb_mon.h b/drivers/usb/mon/usb_mon.h
index 8e0613c..9270283 100644
--- a/drivers/usb/mon/usb_mon.h
+++ b/drivers/usb/mon/usb_mon.h
@@ -27,6 +27,7 @@
struct kref ref; /* Under mon_lock */
/* Stats */
+ unsigned int cnt_events;
unsigned int cnt_text_lost;
};