diff options
| author | Kevin Daughtridge <kevin@kdau.com> | 2012-09-20 12:00:32 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-07 08:39:33 -0700 |
| commit | 8002daf988b55edc56c69b3c824b5a68c258ace3 (patch) | |
| tree | a2d78b932b114c7f32233f39e4d375f630324943 /drivers/hid/hid-core.c | |
| parent | ee537508bdc0c00b96ac497f3d82a68f820e6182 (diff) | |
HID: keep dev_rdesc unmodified and use it for comparisons
commit 86e6b77eb7cf9ca2e9c7092b4dfd588f0a3307b6 upstream.
The dev_rdesc member of the hid_device structure is meant to store the original
report descriptor received from the device, but it is currently passed to any
report_fixup method before it is copied to the rdesc member. This patch uses a
temporary buffer to shield dev_rdesc from the side effects of many HID drivers'
report_fixup implementations.
usbhid's hid_post_reset checks the report descriptor currently returned by the
device against a descriptor that may have been modified by a driver's
report_fixup method. That leaves some devices nonfunctional after a resume, with
a "reset_resume error 1" reported. This patch checks the new descriptor against
the unmodified dev_rdesc instead and uses the original, instead of modified,
report size.
BugLink: http://bugs.launchpad.net/bugs/1049623
Signed-off-by: Kevin Daughtridge <kevin@kdau.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/hid/hid-core.c')
| -rw-r--r-- | drivers/hid/hid-core.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 8bcd168fffae..5de3bb307067 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -757,6 +757,7 @@ int hid_open_report(struct hid_device *device) struct hid_item item; unsigned int size; __u8 *start; + __u8 *buf; __u8 *end; int ret; static int (*dispatch_type[])(struct hid_parser *parser, @@ -775,12 +776,21 @@ int hid_open_report(struct hid_device *device) return -ENODEV; size = device->dev_rsize; + buf = kmemdup(start, size, GFP_KERNEL); + if (buf == NULL) + return -ENOMEM; + if (device->driver->report_fixup) - start = device->driver->report_fixup(device, start, &size); + start = device->driver->report_fixup(device, buf, &size); + else + start = buf; - device->rdesc = kmemdup(start, size, GFP_KERNEL); - if (device->rdesc == NULL) + start = kmemdup(start, size, GFP_KERNEL); + kfree(buf); + if (start == NULL) return -ENOMEM; + + device->rdesc = start; device->rsize = size; parser = vzalloc(sizeof(struct hid_parser)); |