linux-stable.git/drivers/usb/core/devio.c, branch v3.16.78

USB: fix the usbfs flag sanitization for control transfers

2018-12-16T22:09:41+00:00

commit 665c365a77fbfeabe52694aedf3446d5f2f1ce42 upstream.

Commit 7a68d9fb8510 ("USB: usbdevfs: sanitize flags more") checks the
transfer flags for URBs submitted from userspace via usbfs.  However,
the check for whether the USBDEVFS_URB_SHORT_NOT_OK flag should be
allowed for a control transfer was added in the wrong place, before
the code has properly determined the direction of the control
transfer.  (Control transfers are special because for them, the
direction is set by the bRequestType byte of the Setup packet rather
than direction bit of the endpoint address.)

This patch moves code which sets up the allow_short flag for control
transfers down after is_in has been set to the correct value.

Signed-off-by: Alan Stern 
Reported-and-tested-by: syzbot+24a30223a4b609bb802e@syzkaller.appspotmail.com
Fixes: 7a68d9fb8510 ("USB: usbdevfs: sanitize flags more")
CC: Oliver Neukum 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

USB: usbdevfs: restore warning for nonsensical flags

2018-12-16T22:09:22+00:00

commit 81e0403b26d94360abd1f6a57311337973bc82cd upstream.

If we filter flags before they reach the core we need to generate our
own warnings.

Signed-off-by: Oliver Neukum 
Fixes: 0cb54a3e47cb ("USB: debugging code shouldn't alter control flow")
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

USB: usbdevfs: sanitize flags more

2018-12-16T22:09:22+00:00

commit 7a68d9fb851012829c29e770621905529bd9490b upstream.

Requesting a ZERO_PACKET or not is sensible only for output.
In the input direction the device decides.
Likewise accepting short packets makes sense only for input.

This allows operation with panic_on_warn without opening up
a local DOS.

Signed-off-by: Oliver Neukum 
Reported-by: syzbot+843efa30c8821bd69f53@syzkaller.appspotmail.com
Fixes: 0cb54a3e47cb ("USB: debugging code shouldn't alter control flow")
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings

USB: usbfs: Filter flags passed in from user space

2018-03-03T15:51:35+00:00

commit 446f666da9f019ce2ffd03800995487e79a91462 upstream.

USBDEVFS_URB_ISO_ASAP must be accepted only for ISO endpoints.
Improve sanity checking.

Reported-by: Andrey Konovalov 
Signed-off-by: Oliver Neukum 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings

USB: usbfs: compute urb->actual_length for isochronous

2018-02-13T18:42:19+00:00

commit 2ef47001b3ee3ded579b7532ebdcf8680e4d8c54 upstream.

The USB kerneldoc says that the actual_length field "is read in
non-iso completion functions", but the usbfs driver uses it for all
URB types in processcompl().  Since not all of the host controller
drivers set actual_length for isochronous URBs, programs using usbfs
with some host controllers don't work properly.  For example, Minas
reports that a USB camera controlled by libusb doesn't work properly
with a dwc2 controller.

It doesn't seem worthwhile to change the HCDs and the documentation,
since the in-kernel USB class drivers evidently don't rely on
actual_length for isochronous transfers.  The easiest solution is for
usbfs to calculate the actual_length value for itself, by adding up
the lengths of the individual packets in an isochronous transfer.

Signed-off-by: Alan Stern 
CC: Minas Harutyunyan 
Reported-and-tested-by: wlf 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

USB: core: Avoid race of async_completed() w/ usbdev_release()

2017-11-26T13:50:24+00:00

commit ed62ca2f4f51c17841ea39d98c0c409cb53a3e10 upstream.

While running reboot tests w/ a specific set of USB devices (and
slub_debug enabled), I found that once every few hours my device would
be crashed with a stack that looked like this:

[   14.012445] BUG: spinlock bad magic on CPU#0, modprobe/2091
[   14.012460]  lock: 0xffffffc0cb055978, .magic: ffffffc0, .owner: cryption contexts: %lu/%lu
[   14.012460] /1025536097, .owner_cpu: 0
[   14.012466] CPU: 0 PID: 2091 Comm: modprobe Not tainted 4.4.79 #352
[   14.012468] Hardware name: Google Kevin (DT)
[   14.012471] Call trace:
[   14.012483] [<....>] dump_backtrace+0x0/0x160
[   14.012487] [<....>] show_stack+0x20/0x28
[   14.012494] [<....>] dump_stack+0xb4/0xf0
[   14.012500] [<....>] spin_dump+0x8c/0x98
[   14.012504] [<....>] spin_bug+0x30/0x3c
[   14.012508] [<....>] do_raw_spin_lock+0x40/0x164
[   14.012515] [<....>] _raw_spin_lock_irqsave+0x64/0x74
[   14.012521] [<....>] __wake_up+0x2c/0x60
[   14.012528] [<....>] async_completed+0x2d0/0x300
[   14.012534] [<....>] __usb_hcd_giveback_urb+0xc4/0x138
[   14.012538] [<....>] usb_hcd_giveback_urb+0x54/0xf0
[   14.012544] [<....>] xhci_irq+0x1314/0x1348
[   14.012548] [<....>] usb_hcd_irq+0x40/0x50
[   14.012553] [<....>] handle_irq_event_percpu+0x1b4/0x3f0
[   14.012556] [<....>] handle_irq_event+0x4c/0x7c
[   14.012561] [<....>] handle_fasteoi_irq+0x158/0x1c8
[   14.012564] [<....>] generic_handle_irq+0x30/0x44
[   14.012568] [<....>] __handle_domain_irq+0x90/0xbc
[   14.012572] [<....>] gic_handle_irq+0xcc/0x18c

Investigation using kgdb() found that the wait queue that was passed
into wake_up() had been freed (it was filled with slub_debug poison).

I analyzed and instrumented the code and reproduced.  My current
belief is that this is happening:

1. async_completed() is called (from IRQ).  Moves "as" onto the
   completed list.
2. On another CPU, proc_reapurbnonblock_compat() calls
   async_getcompleted().  Blocks on spinlock.
3. async_completed() releases the lock; keeps running; gets blocked
   midway through wake_up().
4. proc_reapurbnonblock_compat() => async_getcompleted() gets the
   lock; removes "as" from completed list and frees it.
5. usbdev_release() is called.  Frees "ps".
6. async_completed() finally continues running wake_up().  ...but
   wake_up() has a pointer to the freed "ps".

The instrumentation that led me to believe this was based on adding
some trace_printk() calls in a select few functions and then using
kdb's "ftdump" at crash time.  The trace follows (NOTE: in the trace
below I cheated a little bit and added a udelay(1000) in
async_completed() after releasing the spinlock because I wanted it to
trigger quicker):

<...>-2104   0d.h2 13759034us!: async_completed at start: as=ffffffc0cc638200
mtpd-2055    3.... 13759356us : async_getcompleted before spin_lock_irqsave
mtpd-2055    3d..1 13759362us : async_getcompleted after list_del_init: as=ffffffc0cc638200
mtpd-2055    3.... 13759371us+: proc_reapurbnonblock_compat: free_async(ffffffc0cc638200)
mtpd-2055    3.... 13759422us+: async_getcompleted before spin_lock_irqsave
mtpd-2055    3.... 13759479us : usbdev_release at start: ps=ffffffc0cc042080
mtpd-2055    3.... 13759487us : async_getcompleted before spin_lock_irqsave
mtpd-2055    3.... 13759497us!: usbdev_release after kfree(ps): ps=ffffffc0cc042080
<...>-2104   0d.h2 13760294us : async_completed before wake_up(): as=ffffffc0cc638200

To fix this problem we can just move the wake_up() under the ps->lock.
There should be no issues there that I'm aware of.

Signed-off-by: Douglas Anderson 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

USB: core: replace %p with %pK

2017-09-15T17:29:40+00:00

commit 2f964780c03b73de269b08d12aff96a9618d13f3 upstream.

Format specifier %p can leak kernel addresses while not valuing the
kptr_restrict system settings. When kptr_restrict is set to (1), kernel
pointers printed using the %pK format specifier will be replaced with
Zeros. Debugging Note : &pK prints only Zeros as address. If you need
actual address information, write 0 to kptr_restrict.

echo 0 > /proc/sys/kernel/kptr_restrict

[Found by poking around in a random vendor kernel tree, it would be nice
if someone would actually send these types of patches upstream - gkh]

Signed-off-by: Vamsi Krishna Samavedam 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.16: drop changes in proc_reapurb*(), usbdev_do_ioctl()]
Signed-off-by: Ben Hutchings

USB: avoid left shift by -1

2016-11-20T01:17:16+00:00

commit 53e5f36fbd2453ad69a3369a1db62dc06c30a4aa upstream.

UBSAN complains about a left shift by -1 in proc_do_submiturb().  This
can occur when an URB is submitted for a bulk or control endpoint on
a high-speed device, since the code doesn't bother to check the
endpoint type; normally only interrupt or isochronous endpoints have
a nonzero bInterval value.

Aside from the fact that the operation is illegal, it shouldn't matter
because the result isn't used.  Still, in theory it could cause a
hardware exception or other problem, so we should work around it.
This patch avoids doing the left shift unless the shift amount is >= 0.

The same piece of code has another problem.  When checking the device
speed (the exponential encoding for interrupt endpoints is used only
by high-speed or faster devices), we need to look for speed >=
USB_SPEED_SUPER as well as speed == USB_SPEED HIGH.  The patch adds
this check.

Signed-off-by: Alan Stern 
Reported-by: Vittorio Zecca 
Tested-by: Vittorio Zecca 
Suggested-by: Bjørn Mork 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

USB: usbfs: fix potential infoleak in devio

2016-08-22T21:38:27+00:00

commit 681fef8380eb818c0b845fca5d2ab1dcbab114ee upstream.

The stack object “ci” has a total size of 8 bytes. Its last 3 bytes
are padding bytes which are not initialized and leaked to userland
via “copy_to_user”.

Signed-off-by: Kangjie Lu 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

USB: usbfs: allow URBs to be reaped after disconnection

2015-08-11T08:57:29+00:00

commit 3f2cee73b650921b2e214bf487b2061a1c266504 upstream.

The usbfs API has a peculiar hole: Users are not allowed to reap their
URBs after the device has been disconnected.  There doesn't seem to be
any good reason for this; it is an ad-hoc inconsistency.

The patch allows users to issue the USBDEVFS_REAPURB and
USBDEVFS_REAPURBNDELAY ioctls (together with their 32-bit counterparts
on 64-bit systems) even after the device is gone.  If no URBs are
pending for a disconnected device then the ioctls will return -ENODEV
rather than -EAGAIN, because obviously no new URBs will ever be able
to complete.

The patch also adds a new capability flag for
USBDEVFS_GET_CAPABILITIES to indicate that the reap-after-disconnect
feature is supported.

Signed-off-by: Alan Stern 
Tested-by: Chris Dickens 
Acked-by: Hans de Goede 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Luis Henriques