The handling of large output bulk transfers is broken; the same user
page is read over and over again. Fixed with this patch.
Cc: stable <stable@vger.kernel.org>
Acked-by: Peter Stuge <peter@stuge.se>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Apps which deal with devices which also have a kernel driver, need to do
the following:
1) Check which driver is attached, so as to not detach the wrong driver
(ie detaching usbfs while another instance of the app is using the device)
2) Detach the kernel driver
3) Claim the interface
Where moving from one step to the next for both 1-2 and 2-3 consists of
a (small) race window. So currently such apps are racy and people just live
with it.
This patch adds a new ioctl which makes it possible for apps to do this
in a race free manner. For flexibility apps can choose to:
1) Specify the driver to disconnect
2) Specify to disconnect any driver except for the one named by the app
3) Disconnect any driver
Note that if there is no driver attached, the ioctl will just act like the
regular claim-interface ioctl, this is by design, as returning an error for
this condition would open a new bag of race-conditions.
Changes in v2:
-Fix indentation of if blocks where the condition spans multiple lines
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When using urb->transfer_buffer we need to allocate physical contiguous buffers
for the entire transfer, which is pretty much guaranteed to fail with large
transfers.
Currently userspace works around this by breaking large transfers into multiple
urbs. For large bulk transfers this leads to all kind of complications.
This patch makes it possible for userspace to reliable submit large bulk
transfers to scatter-gather capable host controllers in one go, by using a
scatterlist to break the transfer up in managable chunks.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are a few (new) usbdevfs capabilities which an application cannot
discover in any other way then checking the kernel version. There are 3
problems with this:
1) It is just not very pretty.
2) Given the tendency of enterprise distros to backport stuff it is not
reliable.
3) As discussed in length on the mailinglist, USBDEVFS_URB_BULK_CONTINUATION
does not work as it should when combined with USBDEVFS_URB_SHORT_NOT_OK
(which is its intended use) on devices attached to an XHCI controller.
So the availability of these features can be host controller dependent,
making depending on them based on the kernel version not a good idea.
This patch besides adding the new ioctl also adds flags for the following
existing capabilities:
USBDEVFS_CAP_ZERO_PACKET, available since 2.6.31
USBDEVFS_CAP_BULK_CONTINUATION, available since 2.6.32, except for XHCI
USBDEVFS_CAP_NO_PACKET_SIZE_LIM, available since 3.3
Note that this patch only does not advertise the USBDEVFS_URB_BULK_CONTINUATION
cap for XHCI controllers, bulk transfers with this flag set will still be
accepted when submitted to XHCI controllers.
Returning -EINVAL for them would break existing apps, and in most cases the
troublesome scenario wrt USBDEVFS_URB_SHORT_NOT_OK urbs on XHCI controllers
will never get hit, so this would break working use cases.
The disadvantage of not returning -EINVAL is that cases were it is causing
real trouble may go undetected / the cause of the trouble may be unclear,
but this is the best we can do.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
iso data buffers may have holes in them if some packets were short, so for
iso urbs we should always copy the entire buffer, just like the regular
processcompl does.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There exist races in devio.c, below is one case,
and there are similar races in destroy_async()
and proc_unlinkurb(). Remove these races.
cancel_bulk_urbs() async_completed()
------------------- -----------------------
spin_unlock(&ps->lock);
list_move_tail(&as->asynclist,
&ps->async_completed);
wake_up(&ps->wait);
Lead to free_async() be triggered,
then urb and 'as' will be freed.
usb_unlink_urb(as->urb);
===> refer to the freed 'as'
Signed-off-by: Huajun Li <huajun.li.lee@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oncaphillis <oncaphillis@snafu.de>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This option has been deprecated for many years now, and no userspace
tools use it anymore, so it should be safe to finally remove it.
Reported-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This option has been deprecated for many years now, and no userspace
tools use it anymore, so it should be safe to finally remove it.
Reported-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
module_param(bool) used to counter-intuitively take an int. In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.
It's time to remove the int/unsigned int option. For this version
it'll simply give a warning, but it'll break next kernel version.
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The 16-MB global limit on memory used by usbfs isn't suitable for all
people. It's a reasonable default, but there are applications
(especially for SuperSpeed devices) that need a lot more.
This patch (as1498) creates a writable module parameter for usbcore to
control the global limit. The default is still 16 MB, but users can
change it at runtime, even after usbcore has been loaded. As a
special case, setting the value to 0 is treated the same as the hard
limit of 2047 MB.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
For a long time people have complained about the limitations imposed
by usbfs. URBs coming from userspace are not allowed to have transfer
buffers larger than a more-or-less arbitrary maximum.
While it is generally a good idea to avoid large transfer buffers
(because the data has to be bounced to/from a contiguous kernel-space
buffer), it's not the kernel's job to enforce such limits. Programs
should be allowed to submit URBs as large as they like; if there isn't
sufficient contiguous memory available then the submission will fail
with a simple ENOMEM error.
On the other hand, we would like to prevent programs from submitting a
lot of small URBs and using up all the DMA-able kernel memory. To
that end, this patch (as1497) replaces the old limits on individual
transfer buffers with a single global limit on the total amount of
memory in use by usbfs. The global limit is set to 16 MB as a nice
compromise value: not too big, but large enough to hold about 300 ms
of data for high-speed transfers.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1496) unifies the error-return pathways of several
functions in the usbfs driver. This is not a very important change by
itself; it merely prepares the way for the next patch in this series.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add to the dev_state and alloc_async structures the user namespace
corresponding to the uid and euid. Pass these to kill_pid_info_as_uid(),
which can then implement a proper, user-namespace-aware uid check.
Changelog:
Sep 20: Per Oleg's suggestion: Instead of caching and passing user namespace,
uid, and euid each separately, pass a struct cred.
Sep 26: Address Alan Stern's comments: don't define a struct cred at
usbdev_open(), and take and put a cred at async_completed() to
ensure it lasts for the duration of kill_pid_info_as_cred().
Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In the usb printer class specific request get_device_id the value of
wIndex is (interface << 8 | altsetting) instead of just interface.
This enables the detection of some printers with libusb.
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Matthias Dellweg <2500@gmx.de>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Alan Stern points out that after spin_unlock(&ps->lock) there is no
guarantee that ps->pid won't be freed. Since kill_pid_info_as_uid() is
called after the spin_unlock(), the pid passed to it must be pinned.
Reported-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When `echo Y > /sys/module/usbcore/parameters/usbfs_snoop` and
usb_control_msg() returns error, a lot of kernel memory is dumped to dmesg
until unhandled kernel paging request occurs.
Signed-off-by: Michal Sojka <sojkam1@fel.cvut.cz>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The big kernel lock has been removed from all these files at some point,
leaving only the #include.
Remove this too as a cleanup.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Structure usbdevfs_connectinfo is copied to userland with padding byted
after "slow" field uninitialized. It leads to leaking of contents of
kernel stack memory.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
And audit all the users. None needed the BKL. That was easy
because there was only very few around.
Tested with allmodconfig build on x86-64
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
From: Andi Kleen <ak@linux.intel.com>
The usbcore headers: hcd.h and hub.h are shared between usbcore,
HCDs and a couple of other drivers (e.g. USBIP modules).
So, it makes sense to move them into a more public location and
to cleanup dependency of those modules on kernel internal headers.
This patch moves hcd.h from drivers/usb/core into include/linux/usb/
Signed-of-by: Eric Lescouet <eric@lescouet.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1352) fixes a bug in the way isochronous input data is
returned to userspace for usbfs transfers. The entire buffer must be
copied, not just the first actual_length bytes, because the individual
packets will be discontiguous if any of them are short.
Reported-by: Markus Rechberger <mrechberger@gmail.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Uses the new snoop function from commit 4c6e8971cb,
but includes the buffer data where appropriate, as before.
Signed-off-by: Chris Frey <cdfrey@foursquare.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Total removal from the ioctl code path except for the outcall
to external modules. Locking is ensured by the normal locks
of usbfs.
Signed-off-by: Oliver Neukum <oliver@neukum.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This pushes BKL down in ioctl handling and drops it
for some important ioctls
Signed-off-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Replace it by
mutex_lock(&file->f_dentry->d_inode->i_mutex);
following the example of the generic method
Signed-off-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Locking had long been changed making BKL redundant.
Simply remove it.
Signed-off-by: Oliver Neukum <oliver@neukum.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1323) changes the locking requirements for
usb_autosuspend_device(), usb_autoresume_device(), and
usb_try_autosuspend_device(). This isn't a very important change;
mainly it's meant to make the locking more uniform.
The most tricky part of the patch involves changes to usbdev_open().
To avoid an ABBA locking problem, it was necessary to reduce the
region protected by usbfs_mutex. Since that mutex now protects only
against simultaneous open and remove, this posed no difficulty -- its
scope was larger than necessary.
And it turns out that usbfs_mutex is no longer needed in
usbdev_release() at all. The list of usbfs "ps" structures is now
protected by the device lock instead of by usbfs_mutex.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1316) adds some error checking to usb_submit_urb().
It's conditional on CONFIG_USB_DEBUG, so it won't affect normal users.
The new check makes sure that the actual type of the endpoint
described by urb->pipe agrees with the type encoded in the pipe value.
The USB error code documentation is updated to include the code
returned by the new check, and the usbfs SUBMITURB handler is updated
to use the correct pipe type when legacy user code tries to submit a
bulk transfer to an interrupt endpoint.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
I notice that the processcompl_compat() function seems to be leaking the
'struct async *as' in the error paths.
I think that the calling convention is fundamentally buggered. The
caller is the one that did the "reap_as()" to get the as thing, the
caller should be the one to free it too.
Freeing it in the caller also means that it very clearly always gets
freed, and avoids the need for any "free in the error case too".
From: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Marcus Meissner <meissner@suse.de>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We need to only copy the data received by the device to userspace, not
the whole kernel buffer, which can contain "stale" data.
Thanks to Marcus Meissner for pointing this out and testing the fix.
Reported-by: Marcus Meissner <meissner@suse.de>
Tested-by: Marcus Meissner <meissner@suse.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Half the compat_ioctl handling is in devio.c, the other
half is in fs/compat_ioctl.c. This moves everything into
one place for consistency.
As a positive side-effect, push down the BKL into the
ioctl methods.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Cc: Alon Bar-Lev <alon.barlev@gmail.com>
Cc: David Vrabel <david.vrabel@csr.com>
Cc: linux-usb@vger.kernel.org
This patch (as1283) adds a new flag, USBDEVFS_URB_BULK_CONTINUATION,
to usbfs. It is intended for userspace libraries such as libusb and
openusb. When they have to break up a single usbfs bulk transfer into
multiple URBs, they will set the flag on all but the first URB of the
series.
If an error other than an unlink occurs, the kernel will automatically
cancel all the following URBs for the same endpoint and refuse to
accept new submissions, until an URB is encountered that is not marked
as a BULK_CONTINUATION. Such an URB would indicate the start of a new
transfer or the presence of an older library, so the kernel returns to
normal operation.
This enables libraries to delimit bulk transfers correctly, even in
the presence of early termination as indicated by short packets.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The current limit only allows isochronous transfers up to 32kbyte/urb,
updating this to 192 kbyte/urb improves the reliability of the
transfer. USB 2.0 transfer is possible with 32kbyte but increases the
chance of corrupted/incomplete data when the system is performing some
other tasks in the background.
http://www.spinics.net/lists/linux-usb/msg19955.html
Signed-off-by: Markus Rechberger <mrechberger@gmail.com>
Cc: Oliver Neukum <oliver@neukum.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1261) reduces the amount of detailed URB information
logged by usbfs when the usbfs_snoop parameter is enabled.
Currently we don't display the final status value for a completed URB.
But we do display the entire data buffer twice: both before submission
and after completion. The after-completion display doesn't limit
itself to the actual_length value. But since usbmon is readily
available in virtually all distributions, there's no reason for usbfs
to print out any buffer contents at all!
So this patch restricts the information to: userspace buffer pointer,
endpoint number, type, and direction, length or actual_length, and
timeout value or status. Now everything fits neatly into a single
line.
Along with those changes, the patch also fixes the snoop output for
the REAPURBNDELAY and REAPURBNDELAY32 ioctls. The current version
omits the 'N' from the names.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1258) implements a feature that users have been asking
for: It gives programs the ability to "claim" a port on a hub, via a
new usbfs ioctl. A device plugged into a "claimed" port will not be
touched by the kernel beyond the immediate necessities of
initialization and enumeration.
In particular, when a device is plugged into a "claimed" port, the
kernel will not select and install a configuration. And when a config
is installed by usbfs or sysfs, the kernel will not probe any drivers
for any of the interfaces. (However the kernel will fetch various
string descriptors during enumeration. One could argue that this
isn't really necessary, but the strings are exported in sysfs.)
The patch does not guarantee exclusive access to these devices; it is
still possible for more than one program to open the device file
concurrently. Programs are responsible for coordinating access among
themselves.
A demonstration program showing how to use the new interface can be
found in an attachment to
http://marc.info/?l=linux-usb&m=124345857431452&w=2
The patch also makes a small simplification to the hub driver,
replacing a bunch of more-or-less useless variants of "out of memory"
with a single message.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1272) changes the error code returned when an open call
for a USB device node fails to locate the corresponding device. The
appropriate error code is -ENODEV, not -ENOENT.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Kay Sievers <kay.sievers@vrfy.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
access_ok() checks must be done on every part of the userspace structure
that is accessed. If access_ok() on one part of the struct succeeded, it
does not imply it will succeed on other parts of the struct. (Does
depend on the architecture implementation of access_ok()).
This changes the __get_user() users to first check access_ok() on the
data structure.
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Cc: stable <stable@kernel.org>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1262) fixes a bug in usbfs: It refuses to accept
zero-length transfers, and it insists that the buffer pointer be valid
even if there is no data being transferred.
The patch also consolidates a bunch of repetitive access_ok() checks
into a single check, which incidentally fixes the lack of such a check
for Isochronous URBs.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch fixes a memory leak in devio.c::processcompl
If writing to user space fails the packet must be discarded, as it
already has been removed from the queue of completed packets.
Signed-off-by: Oliver Neukum <oliver@neukum.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Wireless USB endpoint state has a sequence number and a current
window and not just a single toggle bit. So allow HCDs to provide a
endpoint_reset method and call this or clear the software toggles as
required (after a clear halt, set configuration etc.).
usb_settoggle() and friends are then HCD internal and are moved into
core/hcd.h and all device drivers call usb_reset_endpoint() instead.
If the device endpoint state has been reset (with a clear halt) but
the host endpoint state has not then subsequent data transfers will
not complete. The device will only work again after it is reset or
disconnected.
Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
transfer_buffer_length and actual_length have become unsigned, therefore some
additional conversion of local variables, function arguments and print
specifications is desired.
A test for a negative urb->transfer_buffer_length became obsolete; instead
we ensure that it does not exceed INT_MAX. Also, urb->actual_length is always
less than urb->transfer_buffer_length.
rh_string() does no longer return -EPIPE in the case of an unsupported ID.
Instead its only caller, rh_call_control() does the check.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1223) removes a bunch of unnecessary "inline"
annotations from the usbfs driver.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
To permit a userspace application to associate with WUSB devices
using numeric association, control transfers to unauthenticated WUSB
devices must be allowed.
This requires that wusbcore correctly sets the device state to
UNAUTHENTICATED, DEFAULT and ADDRESS and that control transfers can be
performed to UNAUTHENTICATED devices.
Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The usbfs driver manages a list of completed asynchronous URBs. But
it is too eager to free the entries on this list: destroy_async() gets
called whenever an interface is unbound or a device is removed, and it
deallocates the outstanding struct async entries for all URBs on that
interface or device. This is wrong; the user program should be able
to reap an URB any time after it has completed, regardless of whether
or not the interface is still bound or the device is still present.
This patch (as1222) moves the code for deallocating the completed list
entries from destroy_async() to usbdev_release(). The outstanding
entries won't be freed until the user program has closed the device
file, thereby eliminating any possibility that the remaining URBs
might still be reaped.
This fixes a bug in which a program can hang in the USBDEVFS_REAPURB
ioctl when the device is unplugged.
Reported-and-tested-by: Martin Poupe <martin.poupe@upek.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1198) fixes a conceptual bug: Somewhere along the line
we managed to confuse USB class devices with USB char devices. As a
result, the code to send a disconnect signal to userspace would not be
built if both CONFIG_USB_DEVICE_CLASS and CONFIG_USB_DEVICEFS were
disabled.
The usb_fs_classdev_common_remove() routine has been renamed to
usbdev_remove() and it is now called whenever any USB device is
removed, not just when a class device is unregistered. The notifier
registration and unregistration calls are no longer conditionally
compiled. And since the common removal code will always be called as
part of the char device interface, there's no need to call it again as
part of the usbfs interface; thus the invocation of
usb_fs_classdev_common_remove() has been taken out of
usbfs_remove_device().
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Alon Bar-Lev <alon.barlev@gmail.com>
Tested-by: Alon Bar-Lev <alon.barlev@gmail.com>
Cc: stable <stable@kernel.org>
One minor nit did show up, though. The patch below
seems to make more sense than the code does without it.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Just over a year ago (!) I had this brief exchange with Alan Stern:
>> It seems that the signal that can be used with USBDEVFS_DISCSIGNAL and
>> in usbdevfs_urb.signr is limited to the real-time signals SIGRTMIN to
>> SIGRTMAX. What's the rationale for this restriction? I believe that a
>> process can kill() itself with any signal number, can't it? I was
>> planning to use SIGIO for usbdevfs_urb.signr and SIGTERM (uncaught) for
>> USBDEVFS_DISCSIGNAL. I don't think I'll have a problem with using
>> SIGRTMIN+n instead, but I'm curious to know if there's some subtle
>> problem with the non-real-time signals that I should be aware of.
>
> I don't know of any reason for this restriction.
Since no-one else could think of a reason either, I offer the following
patch which allows any signal to be used with USBDEVFS_DISCSIGNAL and
usbdevfs_urb.signr.
Signed-off-by: Phil Endecott <usbpatch@chezphil.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Wrap current->cred and a few other accessors to hide their actual
implementation.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>