linux-stable.git/drivers/usb/core/devio.c, branch v4.13.2

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

2017-09-09T15:39:19+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

Merge branch 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2017-07-07T03:57:13+00:00

Pull misc compat stuff updates from Al Viro:
 "This part is basically untangling various compat stuff. Compat
  syscalls moved to their native counterparts, getting rid of quite a
  bit of double-copying and/or set_fs() uses. A lot of field-by-field
  copyin/copyout killed off.

   - kernel/compat.c is much closer to containing just the
     copyin/copyout of compat structs. Not all compat syscalls are gone
     from it yet, but it's getting there.

   - ipc/compat_mq.c killed off completely.

   - block/compat_ioctl.c cleaned up; floppy compat ioctls moved to
     drivers/block/floppy.c where they belong. Yes, there are several
     drivers that implement some of the same ioctls. Some are m68k and
     one is 32bit-only pmac. drivers/block/floppy.c is the only one in
     that bunch that can be built on biarch"

* 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  mqueue: move compat syscalls to native ones
  usbdevfs: get rid of field-by-field copyin
  compat_hdio_ioctl: get rid of set_fs()
  take floppy compat ioctls to sodding floppy.c
  ipmi: get rid of field-by-field __get_user()
  ipmi: get COMPAT_IPMICTL_RECEIVE_MSG in sync with the native one
  rt_sigtimedwait(): move compat to native
  select: switch compat_{get,put}_fd_set() to compat_{get,put}_bitmap()
  put_compat_rusage(): switch to copy_to_user()
  sigpending(): move compat to native
  getrlimit()/setrlimit(): move compat to native
  times(2): move compat to native
  compat_{get,put}_bitmap(): use unsafe_{get,put}_user()
  fb_get_fscreeninfo(): don't bother with do_fb_ioctl()
  do_sigaltstack(): lift copying to/from userland into callers
  take compat_sys_old_getrlimit() to native syscall
  trim __ARCH_WANT_SYS_OLD_GETRLIMIT

usbdevfs: get rid of field-by-field copyin

2017-06-29T22:17:52+00:00

Signed-off-by: Al Viro

USB: add usbfs ioctl to retrieve the connection speed

2017-06-13T08:48:24+00:00

The usbfs interface does not provide any way for the user to learn the
speed at which a device is connected.  The current API includes a
USBDEVFS_CONNECTINFO ioctl, but all it provides is the device's
address and a one-bit value indicating whether the connection is low
speed.  That may have sufficed in the era of USB-1.1, but it isn't
good enough today.

This patch introduces a new ioctl, USBDEVFS_GET_SPEED, which returns a
numeric value indicating the speed of the connection: unknown, low,
full, high, wireless, super, or super-plus.

Similar information (not exactly the same) is available through sysfs,
but it seems reasonable to provide the actual value in usbfs.

Signed-off-by: Alan Stern 
Reported-by: Reinhard Huck 
Signed-off-by: Greg Kroah-Hartman

USB: core: replace %p with %pK

2017-05-17T09:27:41+00:00

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 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

sched/headers: Prepare for new header dependencies before moving code to

2017-03-02T07:42:29+00:00

We are going to split  out of , which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder  file that just
maps to  to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

scripts/spelling.txt: add "an one" pattern and fix typo instances

2017-02-28T02:43:46+00:00

Fix typos and add the following to the scripts/spelling.txt:

  an one||a one

I dropped the "an" before "one or more" in
drivers/net/ethernet/sfc/mcdi_pcol.h.

Link: http://lkml.kernel.org/r/1481573103-11329-6-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

USB: Increase usbfs transfer limit

2017-01-10T16:00:42+00:00

Promote a variable keeping track of USB transfer memory usage to a
wider data type and allow for higher bandwidth transfers from a large
number of USB devices connected to a single host.

Signed-off-by: Mateusz Berezecki 
Signed-off-by: Greg Kroah-Hartman

fs: Replace CURRENT_TIME with current_time() for inode timestamps

2016-09-28T01:06:21+00:00

CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_time() instead.

CURRENT_TIME is also not y2038 safe.

This is also in preparation for the patch that transitions
vfs timestamps to use 64 bit time and hence make them
y2038 safe. As part of the effort current_time() will be
extended to do range checks. Hence, it is necessary for all
file system timestamps to use current_time(). Also,
current_time() will be transitioned along with vfs to be
y2038 safe.

Note that whenever a single call to current_time() is used
to change timestamps in different inodes, it is because they
share the same time granularity.

Signed-off-by: Deepa Dinamani 
Reviewed-by: Arnd Bergmann 
Acked-by: Felipe Balbi 
Acked-by: Steven Whitehouse 
Acked-by: Ryusuke Konishi 
Acked-by: David Sterba 
Signed-off-by: Al Viro

USB: avoid left shift by -1

2016-08-23T20:35:20+00:00

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 
CC: 
Signed-off-by: Greg Kroah-Hartman