Commit Graph

34 Commits

Author SHA1 Message Date
Alan Stern 7f85003613 USB: gadgetfs: fix copy_to_user while holding spinlock
commit 6e76c01e71551cb221c1f3deacb9dcd9a7346784 upstream.

The gadgetfs driver as a long-outstanding FIXME, regarding a call of
copy_to_user() made while holding a spinlock.  This patch fixes the
issue by dropping the spinlock and using the dev->udc_usage mechanism
introduced by another recent patch to guard against status changes
while the lock isn't held.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-12 11:51:15 +02:00
Alan Stern fd5336c0d1 USB: gadgetfs: Fix crash caused by inadequate synchronization
commit 520b72fc64debf8a86c3853b8e486aa5982188f0 upstream.

The gadgetfs driver (drivers/usb/gadget/legacy/inode.c) was written
before the UDC and composite frameworks were adopted; it is a legacy
driver.  As such, it expects that once bound to a UDC controller, it
will not be unbound until it unregisters itself.

However, the UDC framework does unbind function drivers while they are
still registered.  When this happens, it can cause the gadgetfs driver
to misbehave or crash.  For example, userspace can cause a crash by
opening the device file and doing an ioctl call before setting up a
configuration (found by Andrey Konovalov using the syzkaller fuzzer).

This patch adds checks and synchronization to prevent these bad
behaviors.  It adds a udc_usage counter that the driver increments at
times when it is using a gadget interface without holding the private
spinlock.  The unbind routine waits for this counter to go to 0 before
returning, thereby ensuring that the UDC is no longer in use.

The patch also adds a check in the dev_ioctl() routine to make sure
the driver is bound to a UDC before dereferencing the gadget pointer,
and it makes destroy_ep_files() synchronize with the endpoint I/O
routines, to prevent the user from accessing an endpoint data
structure after it has been removed.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-12 11:51:15 +02:00
Alan Stern 0c0d3d8730 USB: gadgetfs, dummy-hcd, net2280: fix locking for callbacks
commit f16443a034c7aa359ddf6f0f9bc40d01ca31faea upstream.

Using the syzkaller kernel fuzzer, Andrey Konovalov generated the
following error in gadgetfs:

> BUG: KASAN: use-after-free in __lock_acquire+0x3069/0x3690
> kernel/locking/lockdep.c:3246
> Read of size 8 at addr ffff88003a2bdaf8 by task kworker/3:1/903
>
> CPU: 3 PID: 903 Comm: kworker/3:1 Not tainted 4.12.0-rc4+ #35
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
> Workqueue: usb_hub_wq hub_event
> Call Trace:
>  __dump_stack lib/dump_stack.c:16 [inline]
>  dump_stack+0x292/0x395 lib/dump_stack.c:52
>  print_address_description+0x78/0x280 mm/kasan/report.c:252
>  kasan_report_error mm/kasan/report.c:351 [inline]
>  kasan_report+0x230/0x340 mm/kasan/report.c:408
>  __asan_report_load8_noabort+0x19/0x20 mm/kasan/report.c:429
>  __lock_acquire+0x3069/0x3690 kernel/locking/lockdep.c:3246
>  lock_acquire+0x22d/0x560 kernel/locking/lockdep.c:3855
>  __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
>  _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151
>  spin_lock include/linux/spinlock.h:299 [inline]
>  gadgetfs_suspend+0x89/0x130 drivers/usb/gadget/legacy/inode.c:1682
>  set_link_state+0x88e/0xae0 drivers/usb/gadget/udc/dummy_hcd.c:455
>  dummy_hub_control+0xd7e/0x1fb0 drivers/usb/gadget/udc/dummy_hcd.c:2074
>  rh_call_control drivers/usb/core/hcd.c:689 [inline]
>  rh_urb_enqueue drivers/usb/core/hcd.c:846 [inline]
>  usb_hcd_submit_urb+0x92f/0x20b0 drivers/usb/core/hcd.c:1650
>  usb_submit_urb+0x8b2/0x12c0 drivers/usb/core/urb.c:542
>  usb_start_wait_urb+0x148/0x5b0 drivers/usb/core/message.c:56
>  usb_internal_control_msg drivers/usb/core/message.c:100 [inline]
>  usb_control_msg+0x341/0x4d0 drivers/usb/core/message.c:151
>  usb_clear_port_feature+0x74/0xa0 drivers/usb/core/hub.c:412
>  hub_port_disable+0x123/0x510 drivers/usb/core/hub.c:4177
>  hub_port_init+0x1ed/0x2940 drivers/usb/core/hub.c:4648
>  hub_port_connect drivers/usb/core/hub.c:4826 [inline]
>  hub_port_connect_change drivers/usb/core/hub.c:4999 [inline]
>  port_event drivers/usb/core/hub.c:5105 [inline]
>  hub_event+0x1ae1/0x3d40 drivers/usb/core/hub.c:5185
>  process_one_work+0xc08/0x1bd0 kernel/workqueue.c:2097
>  process_scheduled_works kernel/workqueue.c:2157 [inline]
>  worker_thread+0xb2b/0x1860 kernel/workqueue.c:2233
>  kthread+0x363/0x440 kernel/kthread.c:231
>  ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:424
>
> Allocated by task 9958:
>  save_stack_trace+0x1b/0x20 arch/x86/kernel/stacktrace.c:59
>  save_stack+0x43/0xd0 mm/kasan/kasan.c:513
>  set_track mm/kasan/kasan.c:525 [inline]
>  kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:617
>  kmem_cache_alloc_trace+0x87/0x280 mm/slub.c:2745
>  kmalloc include/linux/slab.h:492 [inline]
>  kzalloc include/linux/slab.h:665 [inline]
>  dev_new drivers/usb/gadget/legacy/inode.c:170 [inline]
>  gadgetfs_fill_super+0x24f/0x540 drivers/usb/gadget/legacy/inode.c:1993
>  mount_single+0xf6/0x160 fs/super.c:1192
>  gadgetfs_mount+0x31/0x40 drivers/usb/gadget/legacy/inode.c:2019
>  mount_fs+0x9c/0x2d0 fs/super.c:1223
>  vfs_kern_mount.part.25+0xcb/0x490 fs/namespace.c:976
>  vfs_kern_mount fs/namespace.c:2509 [inline]
>  do_new_mount fs/namespace.c:2512 [inline]
>  do_mount+0x41b/0x2d90 fs/namespace.c:2834
>  SYSC_mount fs/namespace.c:3050 [inline]
>  SyS_mount+0xb0/0x120 fs/namespace.c:3027
>  entry_SYSCALL_64_fastpath+0x1f/0xbe
>
> Freed by task 9960:
>  save_stack_trace+0x1b/0x20 arch/x86/kernel/stacktrace.c:59
>  save_stack+0x43/0xd0 mm/kasan/kasan.c:513
>  set_track mm/kasan/kasan.c:525 [inline]
>  kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:590
>  slab_free_hook mm/slub.c:1357 [inline]
>  slab_free_freelist_hook mm/slub.c:1379 [inline]
>  slab_free mm/slub.c:2961 [inline]
>  kfree+0xed/0x2b0 mm/slub.c:3882
>  put_dev+0x124/0x160 drivers/usb/gadget/legacy/inode.c:163
>  gadgetfs_kill_sb+0x33/0x60 drivers/usb/gadget/legacy/inode.c:2027
>  deactivate_locked_super+0x8d/0xd0 fs/super.c:309
>  deactivate_super+0x21e/0x310 fs/super.c:340
>  cleanup_mnt+0xb7/0x150 fs/namespace.c:1112
>  __cleanup_mnt+0x1b/0x20 fs/namespace.c:1119
>  task_work_run+0x1a0/0x280 kernel/task_work.c:116
>  exit_task_work include/linux/task_work.h:21 [inline]
>  do_exit+0x18a8/0x2820 kernel/exit.c:878
>  do_group_exit+0x14e/0x420 kernel/exit.c:982
>  get_signal+0x784/0x1780 kernel/signal.c:2318
>  do_signal+0xd7/0x2130 arch/x86/kernel/signal.c:808
>  exit_to_usermode_loop+0x1ac/0x240 arch/x86/entry/common.c:157
>  prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
>  syscall_return_slowpath+0x3ba/0x410 arch/x86/entry/common.c:263
>  entry_SYSCALL_64_fastpath+0xbc/0xbe
>
> The buggy address belongs to the object at ffff88003a2bdae0
>  which belongs to the cache kmalloc-1024 of size 1024
> The buggy address is located 24 bytes inside of
>  1024-byte region [ffff88003a2bdae0, ffff88003a2bdee0)
> The buggy address belongs to the page:
> page:ffffea0000e8ae00 count:1 mapcount:0 mapping:          (null)
> index:0x0 compound_mapcount: 0
> flags: 0x100000000008100(slab|head)
> raw: 0100000000008100 0000000000000000 0000000000000000 0000000100170017
> raw: ffffea0000ed3020 ffffea0000f5f820 ffff88003e80efc0 0000000000000000
> page dumped because: kasan: bad access detected
>
> Memory state around the buggy address:
>  ffff88003a2bd980: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>  ffff88003a2bda00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> >ffff88003a2bda80: fc fc fc fc fc fc fc fc fc fc fc fc fb fb fb fb
>                                                                 ^
>  ffff88003a2bdb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>  ffff88003a2bdb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ==================================================================

What this means is that the gadgetfs_suspend() routine was trying to
access dev->lock after it had been deallocated.  The root cause is a
race in the dummy_hcd driver; the dummy_udc_stop() routine can race
with the rest of the driver because it contains no locking.  And even
when proper locking is added, it can still race with the
set_link_state() function because that function incorrectly drops the
private spinlock before invoking any gadget driver callbacks.

The result of this race, as seen above, is that set_link_state() can
invoke a callback in gadgetfs even after gadgetfs has been unbound
from dummy_hcd's UDC and its private data structures have been
deallocated.

include/linux/usb/gadget.h documents that the ->reset, ->disconnect,
->suspend, and ->resume callbacks may be invoked in interrupt context.
In general this is necessary, to prevent races with gadget driver
removal.  This patch fixes dummy_hcd to retain the spinlock across
these calls, and it adds a spinlock acquisition to dummy_udc_stop() to
prevent the race.

The net2280 driver makes the same mistake of dropping the private
spinlock for its ->disconnect and ->reset callback invocations.  The
patch fixes it too.

Lastly, since gadgetfs_suspend() may be invoked in interrupt context,
it cannot assume that interrupts are enabled when it runs.  It must
use spin_lock_irqsave() instead of spin_lock_irq().  The patch fixes
that bug as well.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-24 07:11:16 +02:00
Alan Stern 3ff5f4f6a8 USB: gadget: fix GPF in gadgetfs
commit f50b878fed33e360d01dcdc31a8eeb1815d033d5 upstream.

A NULL-pointer dereference bug in gadgetfs was uncovered by syzkaller:

> kasan: GPF could be caused by NULL-ptr deref or user memory access
> general protection fault: 0000 [#1] SMP KASAN
> Dumping ftrace buffer:
>    (ftrace buffer empty)
> Modules linked in:
> CPU: 2 PID: 4820 Comm: syz-executor0 Not tainted 4.12.0-rc4+ #5
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
> task: ffff880039542dc0 task.stack: ffff88003bdd0000
> RIP: 0010:__list_del_entry_valid+0x7e/0x170 lib/list_debug.c:51
> RSP: 0018:ffff88003bdd6e50 EFLAGS: 00010246
> RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000010000
> RDX: 0000000000000000 RSI: ffffffff86504948 RDI: ffffffff86504950
> RBP: ffff88003bdd6e68 R08: ffff880039542dc0 R09: ffffffff8778ce00
> R10: ffff88003bdd6e68 R11: dffffc0000000000 R12: 0000000000000000
> R13: dffffc0000000000 R14: 1ffff100077badd2 R15: ffffffff864d2e40
> FS:  0000000000000000(0000) GS:ffff88006dc00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 000000002014aff9 CR3: 0000000006022000 CR4: 00000000000006e0
> Call Trace:
>  __list_del_entry include/linux/list.h:116 [inline]
>  list_del include/linux/list.h:124 [inline]
>  usb_gadget_unregister_driver+0x166/0x4c0 drivers/usb/gadget/udc/core.c:1387
>  dev_release+0x80/0x160 drivers/usb/gadget/legacy/inode.c:1187
>  __fput+0x332/0x7f0 fs/file_table.c:209
>  ____fput+0x15/0x20 fs/file_table.c:245
>  task_work_run+0x19b/0x270 kernel/task_work.c:116
>  exit_task_work include/linux/task_work.h:21 [inline]
>  do_exit+0x18a3/0x2820 kernel/exit.c:878
>  do_group_exit+0x149/0x420 kernel/exit.c:982
>  get_signal+0x77f/0x1780 kernel/signal.c:2318
>  do_signal+0xd2/0x2130 arch/x86/kernel/signal.c:808
>  exit_to_usermode_loop+0x1a7/0x240 arch/x86/entry/common.c:157
>  prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
>  syscall_return_slowpath+0x3ba/0x410 arch/x86/entry/common.c:263
>  entry_SYSCALL_64_fastpath+0xbc/0xbe
> RIP: 0033:0x4461f9
> RSP: 002b:00007fdac2b1ecf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
> RAX: fffffffffffffe00 RBX: 00000000007080c8 RCX: 00000000004461f9
> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000007080c8
> RBP: 00000000007080a8 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
> R13: 0000000000000000 R14: 00007fdac2b1f9c0 R15: 00007fdac2b1f700
> Code: 00 00 00 00 ad de 49 39 c4 74 6a 48 b8 00 02 00 00 00 00 ad de
> 48 89 da 48 39 c3 74 74 48 c1 ea 03 48 b8 00 00 00 00 00 fc ff df <80>
> 3c 02 00 0f 85 92 00 00 00 48 8b 13 48 39 f2 75 66 49 8d 7c
> RIP: __list_del_entry_valid+0x7e/0x170 lib/list_debug.c:51 RSP: ffff88003bdd6e50
> ---[ end trace 30e94b1eec4831c8 ]---
> Kernel panic - not syncing: Fatal exception

The bug was caused by dev_release() failing to turn off its
gadget_registered flag after unregistering the gadget driver.  As a
result, when a later user closed the device file before writing a
valid set of descriptors, dev_release() thought the gadget had been
registered and tried to unregister it, even though it had not been.
This led to the NULL pointer dereference.

The fix is simple: turn off the flag when the gadget is unregistered.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-24 07:11:16 +02:00
Alan Stern da4543b3bc USB: gadgetfs: fix checks of wTotalLength in config descriptors
commit 1c069b057dcf64fada952eaa868d35f02bb0cfc2 upstream.

Andrey Konovalov's fuzz testing of gadgetfs showed that we should
improve the driver's checks for valid configuration descriptors passed
in by the user.  In particular, the driver needs to verify that the
wTotalLength value in the descriptor is not too short (smaller
than USB_DT_CONFIG_SIZE).  And the check for whether wTotalLength is
too large has to be changed, because the driver assumes there is
always enough room remaining in the buffer to hold a device descriptor
(at least USB_DT_DEVICE_SIZE bytes).

This patch adds the additional check and fixes the existing check.  It
may do a little more than strictly necessary, but one extra check
won't hurt.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:39:10 +01:00
Alan Stern 46427c247b USB: gadgetfs: fix use-after-free bug
commit add333a81a16abbd4f106266a2553677a165725f upstream.

Andrey Konovalov reports that fuzz testing with syzkaller causes a
KASAN use-after-free bug report in gadgetfs:

BUG: KASAN: use-after-free in gadgetfs_setup+0x208a/0x20e0 at addr ffff88003dfe5bf2
Read of size 2 by task syz-executor0/22994
CPU: 3 PID: 22994 Comm: syz-executor0 Not tainted 4.9.0-rc7+ #16
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 ffff88006df06a18 ffffffff81f96aba ffffffffe0528500 1ffff1000dbe0cd6
 ffffed000dbe0cce ffff88006df068f0 0000000041b58ab3 ffffffff8598b4c8
 ffffffff81f96828 1ffff1000dbe0ccd ffff88006df06708 ffff88006df06748
Call Trace:
 <IRQ> [  201.343209]  [<     inline     >] __dump_stack lib/dump_stack.c:15
 <IRQ> [  201.343209]  [<ffffffff81f96aba>] dump_stack+0x292/0x398 lib/dump_stack.c:51
 [<ffffffff817e4dec>] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
 [<     inline     >] print_address_description mm/kasan/report.c:197
 [<ffffffff817e5080>] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
 [<     inline     >] kasan_report mm/kasan/report.c:306
 [<ffffffff817e562a>] __asan_report_load_n_noabort+0x3a/0x40 mm/kasan/report.c:337
 [<     inline     >] config_buf drivers/usb/gadget/legacy/inode.c:1298
 [<ffffffff8322c8fa>] gadgetfs_setup+0x208a/0x20e0 drivers/usb/gadget/legacy/inode.c:1368
 [<ffffffff830fdcd0>] dummy_timer+0x11f0/0x36d0 drivers/usb/gadget/udc/dummy_hcd.c:1858
 [<ffffffff814807c1>] call_timer_fn+0x241/0x800 kernel/time/timer.c:1308
 [<     inline     >] expire_timers kernel/time/timer.c:1348
 [<ffffffff81482de6>] __run_timers+0xa06/0xec0 kernel/time/timer.c:1641
 [<ffffffff814832c1>] run_timer_softirq+0x21/0x80 kernel/time/timer.c:1654
 [<ffffffff84f4af8b>] __do_softirq+0x2fb/0xb63 kernel/softirq.c:284

The cause of the bug is subtle.  The dev_config() routine gets called
twice by the fuzzer.  The first time, the user data contains both a
full-speed configuration descriptor and a high-speed config
descriptor, causing dev->hs_config to be set.  But it also contains an
invalid device descriptor, so the buffer containing the descriptors is
deallocated and dev_config() returns an error.

The second time dev_config() is called, the user data contains only a
full-speed config descriptor.  But dev->hs_config still has the stale
pointer remaining from the first call, causing the routine to think
that there is a valid high-speed config.  Later on, when the driver
dereferences the stale pointer to copy that descriptor, we get a
use-after-free access.

The fix is simple: Clear dev->hs_config if the passed-in data does not
contain a high-speed config descriptor.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:39:10 +01:00
Alan Stern b946777664 USB: gadgetfs: fix unbounded memory allocation bug
commit faab50984fe6636e616c7cc3d30308ba391d36fd upstream.

Andrey Konovalov reports that fuzz testing with syzkaller causes a
KASAN warning in gadgetfs:

BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr ffff88003c47e160
Write of size 65537 by task syz-executor0/6356
CPU: 3 PID: 6356 Comm: syz-executor0 Not tainted 4.9.0-rc7+ #19
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 ffff88003c107ad8 ffffffff81f96aba ffffffff3dc11ef0 1ffff10007820eee
 ffffed0007820ee6 ffff88003dc11f00 0000000041b58ab3 ffffffff8598b4c8
 ffffffff81f96828 ffffffff813fb4a0 ffff88003b6eadc0 ffff88003c107738
Call Trace:
 [<     inline     >] __dump_stack lib/dump_stack.c:15
 [<ffffffff81f96aba>] dump_stack+0x292/0x398 lib/dump_stack.c:51
 [<ffffffff817e4dec>] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
 [<     inline     >] print_address_description mm/kasan/report.c:197
 [<ffffffff817e5080>] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
 [<ffffffff817e5705>] kasan_report+0x35/0x40 mm/kasan/report.c:306
 [<     inline     >] check_memory_region_inline mm/kasan/kasan.c:308
 [<ffffffff817e3fb9>] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315
 [<ffffffff817e4044>] kasan_check_write+0x14/0x20 mm/kasan/kasan.c:326
 [<     inline     >] copy_from_user arch/x86/include/asm/uaccess.h:689
 [<     inline     >] ep0_write drivers/usb/gadget/legacy/inode.c:1135
 [<ffffffff83228caf>] dev_config+0x86f/0x1190 drivers/usb/gadget/legacy/inode.c:1759
 [<ffffffff817fdd55>] __vfs_write+0x5d5/0x760 fs/read_write.c:510
 [<ffffffff817ff650>] vfs_write+0x170/0x4e0 fs/read_write.c:560
 [<     inline     >] SYSC_write fs/read_write.c:607
 [<ffffffff81803a5b>] SyS_write+0xfb/0x230 fs/read_write.c:599
 [<ffffffff84f47ec1>] entry_SYSCALL_64_fastpath+0x1f/0xc2

Indeed, there is a comment saying that the value of len is restricted
to a 16-bit integer, but the code doesn't actually do this.

This patch fixes the warning.  It replaces the comment with a
computation that forces the amount of data copied from the user in
ep0_write() to be no larger than the wLength size for the control
transfer, which is a 16-bit quantity.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:39:10 +01:00
Greg Kroah-Hartman 404954e5b8 usb: gadgetfs: restrict upper bound on device configuration size
commit 0994b0a257557e18ee8f0b7c5f0f73fe2b54eec1 upstream.

Andrey Konovalov reported that we were not properly checking the upper
limit before of a device configuration size before calling
memdup_user(), which could cause some problems.

So set the upper limit to PAGE_SIZE * 4, which should be good enough for
all devices.

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:39:09 +01:00
Deepa Dinamani 078cd8279e fs: Replace CURRENT_TIME with current_time() for inode timestamps
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 <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Felipe Balbi <balbi@kernel.org>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-27 21:06:21 -04:00
Mathieu Laurendeau 327b21da88 usb/gadget: fix gadgetfs aio support.
Fix io submissions failing with ENODEV.

Signed-off-by: Mathieu Laurendeau <mat.lau@laposte.net>
Fixes: 7fe3976e0f ("gadget: switch ep_io_operations to ->read_iter/->write_iter")
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-08-11 15:09:47 +03:00
Binyamin Sharet 63196e9896 usb: gadget: fix check in sync read from ep in gadgetfs
When reading synchronously from a non-zero endpoint, gadgetfs will
return -EFAULT even if the read succeeds, due to a bad check of the
copy_to_iter() return value.

This fix compares the return value of copy_to_iter to the amount of
bytes that was passed, and only fails if they are not the same.

Signed-off-by: Binyamin Sharet <s.binyamin@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-08-11 15:09:46 +03:00
Bin Liu d246dcb233 usb: gadget: fix spinlock dead lock in gadgetfs
[   40.467381] =============================================
[   40.473013] [ INFO: possible recursive locking detected ]
[   40.478651] 4.6.0-08691-g7f3db9a #37 Not tainted
[   40.483466] ---------------------------------------------
[   40.489098] usb/733 is trying to acquire lock:
[   40.493734]  (&(&dev->lock)->rlock){-.....}, at: [<bf129288>] ep0_complete+0x18/0xdc [gadgetfs]
[   40.502882]
[   40.502882] but task is already holding lock:
[   40.508967]  (&(&dev->lock)->rlock){-.....}, at: [<bf12a420>] ep0_read+0x20/0x5e0 [gadgetfs]
[   40.517811]
[   40.517811] other info that might help us debug this:
[   40.524623]  Possible unsafe locking scenario:
[   40.524623]
[   40.530798]        CPU0
[   40.533346]        ----
[   40.535894]   lock(&(&dev->lock)->rlock);
[   40.540088]   lock(&(&dev->lock)->rlock);
[   40.544284]
[   40.544284]  *** DEADLOCK ***
[   40.544284]
[   40.550461]  May be due to missing lock nesting notation
[   40.550461]
[   40.557544] 2 locks held by usb/733:
[   40.561271]  #0:  (&f->f_pos_lock){+.+.+.}, at: [<c02a6114>] __fdget_pos+0x40/0x48
[   40.569219]  #1:  (&(&dev->lock)->rlock){-.....}, at: [<bf12a420>] ep0_read+0x20/0x5e0 [gadgetfs]
[   40.578523]
[   40.578523] stack backtrace:
[   40.583075] CPU: 0 PID: 733 Comm: usb Not tainted 4.6.0-08691-g7f3db9a #37
[   40.590246] Hardware name: Generic AM33XX (Flattened Device Tree)
[   40.596625] [<c010ffbc>] (unwind_backtrace) from [<c010c1bc>] (show_stack+0x10/0x14)
[   40.604718] [<c010c1bc>] (show_stack) from [<c04207fc>] (dump_stack+0xb0/0xe4)
[   40.612267] [<c04207fc>] (dump_stack) from [<c01886ec>] (__lock_acquire+0xf68/0x1994)
[   40.620440] [<c01886ec>] (__lock_acquire) from [<c0189528>] (lock_acquire+0xd8/0x238)
[   40.628621] [<c0189528>] (lock_acquire) from [<c06ad6b4>] (_raw_spin_lock_irqsave+0x38/0x4c)
[   40.637440] [<c06ad6b4>] (_raw_spin_lock_irqsave) from [<bf129288>] (ep0_complete+0x18/0xdc [gadgetfs])
[   40.647339] [<bf129288>] (ep0_complete [gadgetfs]) from [<bf10a728>] (musb_g_giveback+0x118/0x1b0 [musb_hdrc])
[   40.657842] [<bf10a728>] (musb_g_giveback [musb_hdrc]) from [<bf108768>] (musb_g_ep0_queue+0x16c/0x188 [musb_hdrc])
[   40.668772] [<bf108768>] (musb_g_ep0_queue [musb_hdrc]) from [<bf12a944>] (ep0_read+0x544/0x5e0 [gadgetfs])
[   40.678963] [<bf12a944>] (ep0_read [gadgetfs]) from [<c0284470>] (__vfs_read+0x20/0x110)
[   40.687414] [<c0284470>] (__vfs_read) from [<c0285324>] (vfs_read+0x88/0x114)
[   40.694864] [<c0285324>] (vfs_read) from [<c0286150>] (SyS_read+0x44/0x9c)
[   40.702051] [<c0286150>] (SyS_read) from [<c0107820>] (ret_fast_syscall+0x0/0x1c)

This is caused by the spinlock bug in ep0_read().
Fix the two other deadlock sources in gadgetfs_setup() too.

Cc: <stable@vger.kernel.org> # v3.16+
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-05-31 11:12:54 +03:00
Kirill A. Shutemov 09cbfeaf1a mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00
Marek Szyprowski 175f712119 usb: gadget: provide interface for legacy gadgets to get UDC name
Since commit 855ed04a37 ("usb: gadget:
udc-core: independent registration of gadgets and gadget drivers") gadget
drivers can not assume that UDC drivers are already available on their
initialization. This broke the HACK, which was used in gadgetfs driver,
to get UDC controller name. This patch removes this hack and replaces it
by additional function in the UDC core (which is usefully only for legacy
drivers, please don't use it in the new code).

Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-03-04 15:14:35 +02:00
Marek Szyprowski 7b0a271d5c usb: gadget: gadgetfs: unregister gadget only if it got successfully registered
Gadgetfs driver called usb_gadget_unregister_driver unconditionally, even
if it didn't register it earlier due to other failures. This patch fixes
this.

Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-02-23 08:51:37 +02:00
Al Viro 5955102c99 wrappers for ->i_mutex access
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 18:04:28 -05:00
David Eccher b7bd98b7db usb: gadget: inode.c: fix unbalanced spin_lock in ep0_write
Fix bad unlock balance: ep0_write enter with the locks locked from
inode.c:1769, hence it must exit with spinlock held to avoid double
unlock in dev_config.

Signed-off-by: David Eccher <d.eccher@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2015-12-16 15:19:11 -06:00
Greg Kroah-Hartman 1ee7eead70 USB: inode.c: move assignment out of if () block
We should not be doing assignments within an if () block
so fix up the code to not do this.

change was created using Coccinelle.

CC: Al Viro <viro@zeniv.linux.org.uk>
CC: Peter Chen <peter.chen@freescale.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
CC: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
CC: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Felipe Balbi <balbi@ti.com>
2015-05-10 16:01:11 +02:00
David Howells 75c3cfa855 VFS: assorted weird filesystems: d_inode() annotations
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:58 -04:00
Al Viro 5d5d568975 make new_sync_{read,write}() static
All places outside of core VFS that checked ->read and ->write for being NULL or
called the methods directly are gone now, so NULL {read,write} with non-NULL
{read,write}_iter will do the right thing in all cases.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:40 -04:00
Christoph Hellwig e2e40f2c1e fs: move struct kiocb to fs.h
struct kiocb now is a generic I/O container, so move it to fs.h.
Also do a #include diet for aio.h while we're at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-25 20:28:11 -04:00
Christoph Hellwig 04b2fa9f8f fs: split generic and aio kiocb
Most callers in the kernel want to perform synchronous file I/O, but
still have to bloat the stack with a full struct kiocb.  Split out
the parts needed in filesystem code from those in the aio code, and
only allocate those needed to pass down argument on the stack.  The
aio code embedds the generic iocb in the one it allocates and can
easily get back to it by using container_of.

Also add a ->ki_complete method to struct kiocb, this is used to call
into the aio code and thus removes the dependency on aio for filesystems
impementing asynchronous operations.  It will also allow other callers
to substitute their own completion callback.

We also add a new ->ki_flags field to work around the nasty layering
violation recently introduced in commit 5e33f6 ("usb: gadget: ffs: add
eventfd notification about ffs events").

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-13 12:10:27 -04:00
Alan Stern 96b62a5719 gadgetfs: really get rid of switching ->f_op
... for ep0 as well

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-08 15:19:03 -04:00
Al Viro d4461a602c gadgetfs: get rid of flipping ->f_op in ep_config()
Final methods start with get_ready_ep(), which will fail unless we have
->state == STATE_EP_ENABLED.  So they'd be failing just fine until that
first write() anyway.  Let's do the following:
	* get_ready_ep() gets a new argument - true when called from
ep_write_iter(), false otherwise.
	* make it quiet when it finds STATE_EP_READY (no printk, that is;
the case won't be impossible after that change).
	* when that new argument is true, treat STATE_EP_READY the same
way as STATE_EP_ENABLED (i.e. return zero and do not unlock).
	* in ep_write_iter(), after success of get_ready_ep() turn
	if (!usb_endpoint_dir_in(&epdata->desc)) {
into
	if (epdata->state == STATE_EP_ENABLED &&
	    !usb_endpoint_dir_in(&epdata->desc)) {
- that logics only applies after config.
	* have ep_config() take kernel-side buffer (i.e. use memcpy()
instead of copy_from_user() in there) and in the "let's call ep_io or
ep_aio" (again, in ep_write_iter()) add "... or ep_config() in case it's
not configured yet"

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-08 13:33:50 -04:00
Al Viro 7fe3976e0f gadget: switch ep_io_operations to ->read_iter/->write_iter
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-17 22:23:33 -05:00
Al Viro f01d35a15f gadgetfs: use-after-free in ->aio_read()
AIO_PREAD requests call ->aio_read() with iovec on caller's stack, so if
we are going to access it asynchronously, we'd better get ourselves
a copy - the one on kernel stack of aio_run_iocb() won't be there
anymore.  function/f_fs.c take care of doing that, legacy/inode.c
doesn't...

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-17 22:23:32 -05:00
Dan Carpenter 42d6cfa0ca usb: gadget: gadgetfs: fix an oops in ep_write()
We try to free an ERR_PTR on this error path.

Fixes: b44be2462d ('usb: gadget: gadgetfs: Free memory allocated by memdup_user()')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2015-01-09 18:15:11 -06:00
Mario Schuknecht b44be2462d usb: gadget: gadgetfs: Free memory allocated by memdup_user()
Commit 3b74c73f8d switched over to memdup_user()
in ep_write() function and removed kfree (kbuf).
memdup_user() function allocates memory which is never freed.

Fixes: 3b74c73 (usb: gadget: inode: switch over to memdup_user())
Cc: <stable@vger.kernel.org> # v3.15+
Signed-off-by: Mario Schuknecht <mario.schuknecht@dresearch-fe.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2014-12-22 10:37:15 -06:00
Linus Torvalds 77c688ac87 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "The big thing in this pile is Eric's unmount-on-rmdir series; we
  finally have everything we need for that.  The final piece of prereqs
  is delayed mntput() - now filesystem shutdown always happens on
  shallow stack.

  Other than that, we have several new primitives for iov_iter (Matt
  Wilcox, culled from his XIP-related series) pushing the conversion to
  ->read_iter()/ ->write_iter() a bit more, a bunch of fs/dcache.c
  cleanups and fixes (including the external name refcounting, which
  gives consistent behaviour of d_move() wrt procfs symlinks for long
  and short names alike) and assorted cleanups and fixes all over the
  place.

  This is just the first pile; there's a lot of stuff from various
  people that ought to go in this window.  Starting with
  unionmount/overlayfs mess...  ;-/"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (60 commits)
  fs/file_table.c: Update alloc_file() comment
  vfs: Deduplicate code shared by xattr system calls operating on paths
  reiserfs: remove pointless forward declaration of struct nameidata
  don't need that forward declaration of struct nameidata in dcache.h anymore
  take dname_external() into fs/dcache.c
  let path_init() failures treated the same way as subsequent link_path_walk()
  fix misuses of f_count() in ppp and netlink
  ncpfs: use list_for_each_entry() for d_subdirs walk
  vfs: move getname() from callers to do_mount()
  gfs2_atomic_open(): skip lookups on hashed dentry
  [infiniband] remove pointless assignments
  gadgetfs: saner API for gadgetfs_create_file()
  f_fs: saner API for ffs_sb_create_file()
  jfs: don't hash direct inode
  [s390] remove pointless assignment of ->f_op in vmlogrdr ->open()
  ecryptfs: ->f_op is never NULL
  android: ->f_op is never NULL
  nouveau: __iomem misannotations
  missing annotation in fs/file.c
  fs: namespace: suppress 'may be used uninitialized' warnings
  ...
2014-10-13 11:28:42 +02:00
Al Viro fb6c3225b4 gadgetfs: saner API for gadgetfs_create_file()
return dentry, not inode.  dev->inode is never used by anything,
don't bother with storing it.

Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-10-09 02:39:14 -04:00
Peter Chen 0eba4550fc usb: gadget: gadgetfs: add reset API at usb_gadget_driver
Add reset API at usb_gadget_driver, it calls disconnect handler currently,
but may do different things in future.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2014-09-09 10:00:06 -05:00
Wei Yongjun 7042e8f2f6 usb: gadget: Fix return value check in ep_write()
In case of error, the function memdup_user() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check
should be replaced with IS_ERR().

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2014-08-19 09:27:24 -05:00
Greg Kroah-Hartman 61fe2d75f1 Merge tag 'usb-for-v3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next
Felipe writes:

usb: patches for v3.17 merge window

Surprisingly enough, while a big set of patches, the majority is
composed of cleanups (using devm_*, fixing sparse errors, moving
code around, adding const, etc).

The highlights are addition of new support for PLX USB338x devices,
and support for USB 2.0-only configurations of the DWC3 IP core.

Signed-of-by: Felipe Balbi <balbi@ti.com>
2014-07-21 11:33:41 -07:00
Andrzej Pietrasiewicz 8443f2d2b7 usb: gadget: Gadget directory cleanup - group legacy gadgets
The drivers/usb/gadget directory contains many files.
Files which are related can be distributed into separate directories.
This patch moves the legacy gadgets (i.e. those not using configfs)
into a separate directory.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2014-07-16 12:14:05 -05:00