Commit Graph

172 Commits

Author SHA1 Message Date
Christian Brauner 3652117f85 eventfd: simplify eventfd_signal()
Ever since the eventfd type was introduced back in 2007 in commit
e1ad7468c7 ("signal/timer/event: eventfd core") the eventfd_signal()
function only ever passed 1 as a value for @n. There's no point in
keeping that additional argument.

Link: https://lore.kernel.org/r/20231122-vfs-eventfd-signal-v2-2-bd549b14ce0c@kernel.org
Acked-by: Xu Yilun <yilun.xu@intel.com>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com> # ocxl
Acked-by: Eric Farman <farman@linux.ibm.com>  # s390
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-11-28 14:08:38 +01:00
Linus Torvalds befaa609f4 hardening updates for v6.7-rc1
- Add LKDTM test for stuck CPUs (Mark Rutland)
 
 - Improve LKDTM selftest behavior under UBSan (Ricardo Cañuelo)
 
 - Refactor more 1-element arrays into flexible arrays (Gustavo A. R. Silva)
 
 - Analyze and replace strlcpy and strncpy uses (Justin Stitt, Azeem Shaikh)
 
 - Convert group_info.usage to refcount_t (Elena Reshetova)
 
 - Add __counted_by annotations (Kees Cook, Gustavo A. R. Silva)
 
 - Add Kconfig fragment for basic hardening options (Kees Cook, Lukas Bulwahn)
 
 - Fix randstruct GCC plugin performance mode to stay in groups (Kees Cook)
 
 - Fix strtomem() compile-time check for small sources (Kees Cook)
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Merge tag 'hardening-v6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull hardening updates from Kees Cook:
 "One of the more voluminous set of changes is for adding the new
  __counted_by annotation[1] to gain run-time bounds checking of
  dynamically sized arrays with UBSan.

   - Add LKDTM test for stuck CPUs (Mark Rutland)

   - Improve LKDTM selftest behavior under UBSan (Ricardo Cañuelo)

   - Refactor more 1-element arrays into flexible arrays (Gustavo A. R.
     Silva)

   - Analyze and replace strlcpy and strncpy uses (Justin Stitt, Azeem
     Shaikh)

   - Convert group_info.usage to refcount_t (Elena Reshetova)

   - Add __counted_by annotations (Kees Cook, Gustavo A. R. Silva)

   - Add Kconfig fragment for basic hardening options (Kees Cook, Lukas
     Bulwahn)

   - Fix randstruct GCC plugin performance mode to stay in groups (Kees
     Cook)

   - Fix strtomem() compile-time check for small sources (Kees Cook)"

* tag 'hardening-v6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (56 commits)
  hwmon: (acpi_power_meter) replace open-coded kmemdup_nul
  reset: Annotate struct reset_control_array with __counted_by
  kexec: Annotate struct crash_mem with __counted_by
  virtio_console: Annotate struct port_buffer with __counted_by
  ima: Add __counted_by for struct modsig and use struct_size()
  MAINTAINERS: Include stackleak paths in hardening entry
  string: Adjust strtomem() logic to allow for smaller sources
  hardening: x86: drop reference to removed config AMD_IOMMU_V2
  randstruct: Fix gcc-plugin performance mode to stay in group
  mailbox: zynqmp: Annotate struct zynqmp_ipi_pdata with __counted_by
  drivers: thermal: tsens: Annotate struct tsens_priv with __counted_by
  irqchip/imx-intmux: Annotate struct intmux_data with __counted_by
  KVM: Annotate struct kvm_irq_routing_table with __counted_by
  virt: acrn: Annotate struct vm_memory_region_batch with __counted_by
  hwmon: Annotate struct gsc_hwmon_platform_data with __counted_by
  sparc: Annotate struct cpuinfo_tree with __counted_by
  isdn: kcapi: replace deprecated strncpy with strscpy_pad
  isdn: replace deprecated strncpy with strscpy
  NFS/flexfiles: Annotate struct nfs4_ff_layout_segment with __counted_by
  nfs41: Annotate struct nfs4_file_layout_dsaddr with __counted_by
  ...
2023-10-30 19:09:55 -10:00
Jeff Layton 9a0518de2b
function: convert to new timestamp accessors
Convert to using the new inode timestamp accessor functions.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20231004185347.80880-10-jlayton@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-18 13:26:17 +02:00
Kees Cook c7c4ac7f47 usb: gadget: f_fs: Annotate struct ffs_buffer with __counted_by
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct ffs_buffer.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: John Keeping <john@keeping.me.uk>
Cc: Udipto Goswami <quic_ugoswami@quicinc.com>
Cc: Linyu Yuan <quic_linyyuan@quicinc.com>
Cc: linux-usb@vger.kernel.org
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915195849.never.275-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
2023-10-02 09:48:52 -07:00
Jeff Layton c7603adcc6 usb: convert to ctime accessor functions
In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-18-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-07-13 10:28:03 +02:00
Uttkarsh Aggarwal efb6b53520 usb: gadget: f_fs: Add unbind event before functionfs_unbind
While exercising the unbind path, with the current implementation
the functionfs_unbind would be calling which waits for the ffs->mutex
to be available, however within the same time ffs_ep0_read is invoked
& if no setup packets are pending, it will invoke function
wait_event_interruptible_exclusive_locked_irq which by definition waits
for the ev.count to be increased inside the same mutex for which
functionfs_unbind is waiting.
This creates deadlock situation because the functionfs_unbind won't
get the lock until ev.count is increased which can only happen if
the caller ffs_func_unbind can proceed further.

Following is the illustration:

	CPU1				CPU2

ffs_func_unbind()		ffs_ep0_read()
				mutex_lock(ffs->mutex)
				wait_event(ffs->ev.count)
functionfs_unbind()
  mutex_lock(ffs->mutex)
  mutex_unlock(ffs->mutex)

ffs_event_add()

<deadlock>

Fix this by moving the event unbind before functionfs_unbind
to ensure the ev.count is incrased properly.

Fixes: 6a19da1110 ("usb: gadget: f_fs: Prevent race during ffs_ep0_queue_wait")
Cc: stable <stable@kernel.org>
Signed-off-by: Uttkarsh Aggarwal <quic_uaggarwa@quicinc.com>
Link: https://lore.kernel.org/r/20230525092854.7992-1-quic_uaggarwa@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-29 15:24:08 +01:00
Greg Kroah-Hartman 8e86652e3e Merge 6.3-rc6 into usb-next
We need the USB fixes in here for testing, and this resolves two merge
conflicts, one pointed out by linux-next:

	drivers/usb/dwc3/dwc3-pci.c
	drivers/usb/host/xhci-pci.c

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-10 08:56:59 +02:00
Sandeep Dhavale d356b3cdd0 usb: gadget: f_fs: Fix ffs_epfile_read_iter to handle ITER_UBUF
iov_iter for ffs_epfile_read_iter can be ITER_UBUF with io_uring.
In that case dup_iter() does not have to allocate anything and it
can return NULL. ffs_epfile_read_iter treats this as a failure and
returns -ENOMEM. Fix it by checking if iter_is_ubuf().

Fixes: 1e23db450c ("io_uring: use iter_ubuf for single range imports")
Signed-off-by: Sandeep Dhavale <dhavale@google.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/20230401060509.3608259-2-dhavale@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05 19:24:01 +02:00
Linyu Yuan f54134b3fc usb: gadget: ffs: remove ENTER() macro
ENTER() used to show function name which called during runtime, ftrace can
be used to get same information, let's remove it.

Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
Link: https://lore.kernel.org/r/1679911940-4727-1-git-send-email-quic_linyyuan@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-29 08:55:58 +02:00
Yuta Hayama 180bb831b2 usb: gadget: f_fs: Fix incorrect version checking of OS descs
Currently, the USB gadget framework supports only version 1.0 of the MS OS
descriptor. OS desc has a field bcdVersion indicating its version, with
v1.0 represented by the value 0x100. However, __ffs_do_os_desc_header()
was expecting the incorrect value 0x1, so allow the correct value 0x100.

The bcdVersion field of the descriptor that is actually sent to the host
is set by composite_setup() (in composite.c) to the fixed value 0x100.
Therefore, it can be understood that __ffs_do_os_desc_header() is only
performing a format check of the OS desc passed to functionfs. If a value
other than 0x100 is accepted, there is no effect on communication over
the USB bus. Indeed, until now __ffs_do_os_desc_header() has only accepted
the incorrect value 0x1, but there was no problem with the communication
over the USB bus.

However, this can be confusing for functionfs userspace drivers. Since
bcdVersion=0x100 is used in actual communication, functionfs should accept
the value 0x100.

Note that the correct value for bcdVersion in OS desc v1.0 is 0x100, but
to avoid breaking old userspace drivers, the value 0x1 is also accepted as
an exception. At this time, a message is output to notify the user to fix
the userspace driver.

Signed-off-by: Yuta Hayama <hayama@lineo.co.jp>
Reviewed-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Link: https://lore.kernel.org/r/290f96db-1877-5137-373a-318e7b4f2dde@lineo.co.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-09 15:34:21 +01:00
Greg Kroah-Hartman 924fb3ec50 Merge 6.2-rc7 into usb-next
We need the USB fixes in here, and this resolves a merge conflict with
the i915 driver as reported in linux-next

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-06 08:33:30 +01:00
Udipto Goswami 921deb9da1 usb: gadget: f_fs: Fix unbalanced spinlock in __ffs_ep0_queue_wait
__ffs_ep0_queue_wait executes holding the spinlock of &ffs->ev.waitq.lock
and unlocks it after the assignments to usb_request are done.
However in the code if the request is already NULL we bail out returning
-EINVAL but never unlocked the spinlock.

Fix this by adding spin_unlock_irq &ffs->ev.waitq.lock before returning.

Fixes: 6a19da1110 ("usb: gadget: f_fs: Prevent race during ffs_ep0_queue_wait")
Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Link: https://lore.kernel.org/r/20230124091149.18647-1-quic_ugoswami@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-24 18:19:39 +01:00
Greg Kroah-Hartman e3e9fc7fa7 Merge 6.2-rc5 into usb-next
We need the USB fixes in here and this resolves merge conflicts as
reported in linux-next in the following files:
	drivers/usb/host/xhci.c
	drivers/usb/host/xhci.h
	drivers/usb/typec/ucsi/ucsi.c

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-23 15:38:08 +01:00
Udipto Goswami ce405d561b usb: gadget: f_fs: Ensure ep0req is dequeued before free_request
As per the documentation, function usb_ep_free_request guarantees
the request will not be queued or no longer be re-queued (or
otherwise used). However, with the current implementation it
doesn't make sure that the request in ep0 isn't reused.

Fix this by dequeuing the ep0req on functionfs_unbind before
freeing the request to align with the definition.

Fixes: ddf8abd259 ("USB: f_fs: the FunctionFS driver")
Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Tested-by: Krishna Kurapati <quic_kriskura@quicinc.com>
Link: https://lore.kernel.org/r/20221215052906.8993-3-quic_ugoswami@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-17 17:07:06 +01:00
Udipto Goswami 6a19da1110 usb: gadget: f_fs: Prevent race during ffs_ep0_queue_wait
While performing fast composition switch, there is a possibility that the
process of ffs_ep0_write/ffs_ep0_read get into a race condition
due to ep0req being freed up from functionfs_unbind.

Consider the scenario that the ffs_ep0_write calls the ffs_ep0_queue_wait
by taking a lock &ffs->ev.waitq.lock. However, the functionfs_unbind isn't
bounded so it can go ahead and mark the ep0req to NULL, and since there
is no NULL check in ffs_ep0_queue_wait we will end up in use-after-free.

Fix this by making a serialized execution between the two functions using
a mutex_lock(ffs->mutex).

Fixes: ddf8abd259 ("USB: f_fs: the FunctionFS driver")
Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Tested-by: Krishna Kurapati <quic_kriskura@quicinc.com>
Link: https://lore.kernel.org/r/20221215052906.8993-2-quic_ugoswami@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-17 17:07:06 +01:00
John Keeping b566d38857 usb: gadget: f_fs: use io_data->status consistently
Commit fb1f16d74e ("usb: gadget: f_fs: change ep->status safe in
ffs_epfile_io()") added a new ffs_io_data::status field to fix lifetime
issues in synchronous requests.

While there are no similar lifetime issues for asynchronous requests
(the separate ep member in ffs_io_data avoids them) using the status
field means the USB request can be freed earlier and that there is more
consistency between the synchronous and asynchronous I/O paths.

Cc: Linyu Yuan <quic_linyyuan@quicinc.com>
Signed-off-by: John Keeping <john@metanate.com>
Reviewed-by: Linyu Yuan <quic_linyyuan@quicinc.com>
Link: https://lore.kernel.org/r/20221124170430.3998755-1-john@metanate.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-06 16:36:52 +01:00
Dan Carpenter f57004b9d9 usb: gadget: f_fs: stricter integer overflow checks
This from static analysis.  The vla_item() takes a size and adds it to
the total.  It has a built in integer overflow check so if it encounters
an integer overflow anywhere then it records the total as SIZE_MAX.

However there is an issue here because the "lang_count*(needed_count+1)"
multiplication can overflow.  Technically the "lang_count + 1" addition
could overflow too, but that would be detected and is harmless.  Fix
both using the new size_add() and size_mul() functions.

Fixes: e6f3862fa1 ("usb: gadget: FunctionFS: Remove VLAIS usage from gadget code")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YxDI3lMYomE7WCjn@kili
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-07 16:23:22 +02:00
Wolfram Sang b7db5733a5 usb: move from strlcpy with unused retval to strscpy
Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Reviewed-by: Richard Leitner <richard.leitner@skidata.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20220818210116.7517-1-wsa+renesas@sang-engineering.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-19 11:08:54 +02:00
Linyu Yuan 0698f0209d usb: gadget: f_fs: change ep->ep safe in ffs_epfile_io()
In ffs_epfile_io(), when read/write data in blocking mode, it will wait
the completion in interruptible mode, if task receive a signal, it will
terminate the wait, at same time, if function unbind occurs,
ffs_func_unbind() will kfree all eps, ffs_epfile_io() still try to
dequeue request by dereferencing ep which may become invalid.

Fix it by add ep spinlock and will not dereference ep if it is not valid.

Cc: <stable@vger.kernel.org> # 5.15
Reported-by: Michael Wu <michael@allwinnertech.com>
Tested-by: Michael Wu <michael@allwinnertech.com>
Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
Link: https://lore.kernel.org/r/1654863478-26228-3-git-send-email-quic_linyyuan@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-10 14:45:38 +02:00
Linyu Yuan fb1f16d74e usb: gadget: f_fs: change ep->status safe in ffs_epfile_io()
If a task read/write data in blocking mode, it will wait the completion
in ffs_epfile_io(), if function unbind occurs, ffs_func_unbind() will
kfree ffs ep, once the task wake up, it still dereference the ffs ep to
obtain the request status.

Fix it by moving the request status to io_data which is stack-safe.

Cc: <stable@vger.kernel.org> # 5.15
Reported-by: Michael Wu <michael@allwinnertech.com>
Tested-by: Michael Wu <michael@allwinnertech.com>
Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
Link: https://lore.kernel.org/r/1654863478-26228-2-git-send-email-quic_linyyuan@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-10 14:45:38 +02:00
Greg Kroah-Hartman fbd533e90d Linux 5.17-rc4
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Merge 5.17-rc4 into usb-next

We need the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-14 09:04:36 +01:00
Udipto Goswami ebe2b1add1 usb: f_fs: Fix use-after-free for epfile
Consider a case where ffs_func_eps_disable is called from
ffs_func_disable as part of composition switch and at the
same time ffs_epfile_release get called from userspace.
ffs_epfile_release will free up the read buffer and call
ffs_data_closed which in turn destroys ffs->epfiles and
mark it as NULL. While this was happening the driver has
already initialized the local epfile in ffs_func_eps_disable
which is now freed and waiting to acquire the spinlock. Once
spinlock is acquired the driver proceeds with the stale value
of epfile and tries to free the already freed read buffer
causing use-after-free.

Following is the illustration of the race:

      CPU1                                  CPU2

   ffs_func_eps_disable
   epfiles (local copy)
					ffs_epfile_release
					ffs_data_closed
					if (last file closed)
					ffs_data_reset
					ffs_data_clear
					ffs_epfiles_destroy
spin_lock
dereference epfiles

Fix this races by taking epfiles local copy & assigning it under
spinlock and if epfiles(local) is null then update it in ffs->epfiles
then finally destroy it.
Extending the scope further from the race, protecting the ep related
structures, and concurrent accesses.

Fixes: a9e6f83c2d ("usb: gadget: f_fs: stop sleeping in ffs_func_eps_disable")
Co-developed-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Pratham Pratap <quic_ppratap@quicinc.com>
Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Link: https://lore.kernel.org/r/1643256595-10797-1-git-send-email-quic_ugoswami@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-31 11:22:05 +01:00
Gustavo A. R. Silva 4213e92ef7 usb: gadget: f_fs: Use struct_size() and flex_array_size() helpers
Make use of the struct_size() and flex_array_size() helpers instead of
an open-coded version, in order to avoid any potential type mistakes
or integer overflows that, in the worst scenario, could lead to heap
overflows.

Also, address the following sparse warnings:
drivers/usb/gadget/function/f_fs.c:922:23: warning: using sizeof on a flexible structure

Link: https://github.com/KSPP/linux/issues/174
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20220120222933.GA35155@embeddedor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 14:02:15 +01:00
Greg Kroah-Hartman e681a9d205 Merge 5.16-rc8 into usb-next
We need the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-03 13:02:29 +01:00
Vincent Pelletier b1e0887379 usb: gadget: f_fs: Clear ffs_eventfd in ffs_data_clear.
ffs_data_clear is indirectly called from both ffs_fs_kill_sb and
ffs_ep0_release, so it ends up being called twice when userland closes ep0
and then unmounts f_fs.
If userland provided an eventfd along with function's USB descriptors, it
ends up calling eventfd_ctx_put as many times, causing a refcount
underflow.
NULL-ify ffs_eventfd to prevent these extraneous eventfd_ctx_put calls.

Also, set epfiles to NULL right after de-allocating it, for readability.

For completeness, ffs_data_clear actually ends up being called thrice, the
last call being before the whole ffs structure gets freed, so when this
specific sequence happens there is a second underflow happening (but not
being reported):

/sys/kernel/debug/tracing# modprobe usb_f_fs
/sys/kernel/debug/tracing# echo ffs_data_clear > set_ftrace_filter
/sys/kernel/debug/tracing# echo function > current_tracer
/sys/kernel/debug/tracing# echo 1 > tracing_on
(setup gadget, run and kill function userland process, teardown gadget)
/sys/kernel/debug/tracing# echo 0 > tracing_on
/sys/kernel/debug/tracing# cat trace
 smartcard-openp-436     [000] .....  1946.208786: ffs_data_clear <-ffs_data_closed
 smartcard-openp-431     [000] .....  1946.279147: ffs_data_clear <-ffs_data_closed
 smartcard-openp-431     [000] .n...  1946.905512: ffs_data_clear <-ffs_data_put

Warning output corresponding to above trace:
[ 1946.284139] WARNING: CPU: 0 PID: 431 at lib/refcount.c:28 refcount_warn_saturate+0x110/0x15c
[ 1946.293094] refcount_t: underflow; use-after-free.
[ 1946.298164] Modules linked in: usb_f_ncm(E) u_ether(E) usb_f_fs(E) hci_uart(E) btqca(E) btrtl(E) btbcm(E) btintel(E) bluetooth(E) nls_ascii(E) nls_cp437(E) vfat(E) fat(E) bcm2835_v4l2(CE) bcm2835_mmal_vchiq(CE) videobuf2_vmalloc(E) videobuf2_memops(E) sha512_generic(E) videobuf2_v4l2(E) sha512_arm(E) videobuf2_common(E) videodev(E) cpufreq_dt(E) snd_bcm2835(CE) brcmfmac(E) mc(E) vc4(E) ctr(E) brcmutil(E) snd_soc_core(E) snd_pcm_dmaengine(E) drbg(E) snd_pcm(E) snd_timer(E) snd(E) soundcore(E) drm_kms_helper(E) cec(E) ansi_cprng(E) rc_core(E) syscopyarea(E) raspberrypi_cpufreq(E) sysfillrect(E) sysimgblt(E) cfg80211(E) max17040_battery(OE) raspberrypi_hwmon(E) fb_sys_fops(E) regmap_i2c(E) ecdh_generic(E) rfkill(E) ecc(E) bcm2835_rng(E) rng_core(E) vchiq(CE) leds_gpio(E) libcomposite(E) fuse(E) configfs(E) ip_tables(E) x_tables(E) autofs4(E) ext4(E) crc16(E) mbcache(E) jbd2(E) crc32c_generic(E) sdhci_iproc(E) sdhci_pltfm(E) sdhci(E)
[ 1946.399633] CPU: 0 PID: 431 Comm: smartcard-openp Tainted: G         C OE     5.15.0-1-rpi #1  Debian 5.15.3-1
[ 1946.417950] Hardware name: BCM2835
[ 1946.425442] Backtrace:
[ 1946.432048] [<c08d60a0>] (dump_backtrace) from [<c08d62ec>] (show_stack+0x20/0x24)
[ 1946.448226]  r7:00000009 r6:0000001c r5:c04a948c r4:c0a64e2c
[ 1946.458412] [<c08d62cc>] (show_stack) from [<c08d9ae0>] (dump_stack+0x28/0x30)
[ 1946.470380] [<c08d9ab8>] (dump_stack) from [<c0123500>] (__warn+0xe8/0x154)
[ 1946.482067]  r5:c04a948c r4:c0a71dc8
[ 1946.490184] [<c0123418>] (__warn) from [<c08d6948>] (warn_slowpath_fmt+0xa0/0xe4)
[ 1946.506758]  r7:00000009 r6:0000001c r5:c0a71dc8 r4:c0a71e04
[ 1946.517070] [<c08d68ac>] (warn_slowpath_fmt) from [<c04a948c>] (refcount_warn_saturate+0x110/0x15c)
[ 1946.535309]  r8:c0100224 r7:c0dfcb84 r6:ffffffff r5:c3b84c00 r4:c24a17c0
[ 1946.546708] [<c04a937c>] (refcount_warn_saturate) from [<c0380134>] (eventfd_ctx_put+0x48/0x74)
[ 1946.564476] [<c03800ec>] (eventfd_ctx_put) from [<bf5464e8>] (ffs_data_clear+0xd0/0x118 [usb_f_fs])
[ 1946.582664]  r5:c3b84c00 r4:c2695b00
[ 1946.590668] [<bf546418>] (ffs_data_clear [usb_f_fs]) from [<bf547cc0>] (ffs_data_closed+0x9c/0x150 [usb_f_fs])
[ 1946.609608]  r5:bf54d014 r4:c2695b00
[ 1946.617522] [<bf547c24>] (ffs_data_closed [usb_f_fs]) from [<bf547da0>] (ffs_fs_kill_sb+0x2c/0x30 [usb_f_fs])
[ 1946.636217]  r7:c0dfcb84 r6:c3a12260 r5:bf54d014 r4:c229f000
[ 1946.646273] [<bf547d74>] (ffs_fs_kill_sb [usb_f_fs]) from [<c0326d50>] (deactivate_locked_super+0x54/0x9c)
[ 1946.664893]  r5:bf54d014 r4:c229f000
[ 1946.672921] [<c0326cfc>] (deactivate_locked_super) from [<c0326df8>] (deactivate_super+0x60/0x64)
[ 1946.690722]  r5:c2a09000 r4:c229f000
[ 1946.698706] [<c0326d98>] (deactivate_super) from [<c0349a28>] (cleanup_mnt+0xe4/0x14c)
[ 1946.715553]  r5:c2a09000 r4:00000000
[ 1946.723528] [<c0349944>] (cleanup_mnt) from [<c0349b08>] (__cleanup_mnt+0x1c/0x20)
[ 1946.739922]  r7:c0dfcb84 r6:c3a12260 r5:c3a126fc r4:00000000
[ 1946.750088] [<c0349aec>] (__cleanup_mnt) from [<c0143d10>] (task_work_run+0x84/0xb8)
[ 1946.766602] [<c0143c8c>] (task_work_run) from [<c010bdc8>] (do_work_pending+0x470/0x56c)
[ 1946.783540]  r7:5ac3c35a r6:c0d0424c r5:c200bfb0 r4:c200a000
[ 1946.793614] [<c010b958>] (do_work_pending) from [<c01000c0>] (slow_work_pending+0xc/0x20)
[ 1946.810553] Exception stack(0xc200bfb0 to 0xc200bff8)
[ 1946.820129] bfa0:                                     00000000 00000000 000000aa b5e21430
[ 1946.837104] bfc0: bef867a0 00000001 bef86840 00000034 bef86838 bef86790 bef86794 bef867a0
[ 1946.854125] bfe0: 00000000 bef86798 b67b7a1c b6d626a4 60000010 b5a23760
[ 1946.865335]  r10:00000000 r9:c200a000 r8:c0100224 r7:00000034 r6:bef86840 r5:00000001
[ 1946.881914]  r4:bef867a0
[ 1946.888793] ---[ end trace 7387f2a9725b28d0 ]---

Fixes: 5e33f6fdf7 ("usb: gadget: ffs: add eventfd notification about ffs events")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Vincent Pelletier <plr.vincent@gmail.com>
Link: https://lore.kernel.org/r/f79eeea29f3f98de6782a064ec0f7351ad2f598f.1639793920.git.plr.vincent@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-21 09:05:21 +01:00
Pavankumar Kondeti c76ef96fc0 usb: gadget: f_fs: Use stream_open() for endpoint files
Function fs endpoint file operations are synchronized via an interruptible
mutex wait. However we see threads that do ep file operations concurrently
are getting blocked for the mutex lock in __fdget_pos(). This is an
uninterruptible wait and we see hung task warnings and kernel panic
if hung_task_panic systcl is enabled if host does not send/receive
the data for long time.

The reason for threads getting blocked in __fdget_pos() is due to
the file position protection introduced by the commit 9c225f2655
("vfs: atomic f_pos accesses as per POSIX"). Since function fs
endpoint files does not have the notion of the file position, switch
to the stream mode. This will bypass the file position mutex and
threads will be blocked in interruptible state for the function fs
mutex.

It should not affects user space as we are only changing the task state
changes the task state from UNINTERRUPTIBLE to INTERRUPTIBLE while waiting
for the USB transfers to be finished. However there is a slight change to
the O_NONBLOCK behavior. Earlier threads that are using O_NONBLOCK are also
getting blocked inside fdget_pos(). Now they reach to function fs and error
code is returned. The non blocking behavior is actually honoured now.

Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Link: https://lore.kernel.org/r/1636712682-1226-1-git-send-email-quic_pkondeti@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-17 14:34:42 +01:00
Jens Axboe 6b19b766e8 fs: get rid of the res2 iocb->ki_complete argument
The second argument was only used by the USB gadget code, yet everyone
pays the overhead of passing a zero to be passed into aio, where it
ends up being part of the aio res2 value.

Now that everybody is passing in zero, kill off the extra argument.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-25 10:36:24 -06:00
Jens Axboe 4c3d8accdc usb: remove res2 argument from gadget code completions
The USB gadget code is the only code that every tried to utilize the
2nd argument of the aio completions, but there are strong suspicions
that it was never actually used by anything on the userspace side.

Out of the 3 cases that touch it, two of them just pass in the same
as res, and the last one passes in error/transfer in res like any
other normal use case.

Remove the 2nd argument, pass 0 like the rest of the in-kernel users
of kiocb based IO.

Link: https://lore.kernel.org/linux-block/20211021174021.273c82b1.john@metanate.com/
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-25 09:28:38 -06:00
Salah Triki 90059e9395 usb: gadget: remove useless cast
Remove the cast done by ERR_PTR() and PTR_ERR() since data is of type char
* and fss_prepare_buffer() should returns a value of this type.

Acked-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Salah Triki <salah.triki@gmail.com>
Link: https://lore.kernel.org/r/20210731171838.GA912463@pc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-05 12:31:27 +02:00
Wei Ming Chen 9311a53106 usb: gadget: Fix inconsistent indent
Remove whitespace and use tab as indent

Acked-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Wei Ming Chen <jj251510319013@gmail.com>
Link: https://lore.kernel.org/r/20210801055454.53015-1-jj251510319013@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-05 12:31:22 +02:00
Greg Kroah-Hartman 37fdb7c90f Linux 5.13-rc6
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Merge tag 'v5.13-rc6' into usb-next

We want the usb fixes in here as well, and this resolves some merge
issues with:
	drivers/usb/dwc3/debugfs.c
	drivers/usb/dwc3/gadget.c

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-14 09:18:07 +02:00
Andrew Gabbasov ecfbd7b905 usb: gadget: f_fs: Fix setting of device and driver data cross-references
FunctionFS device structure 'struct ffs_dev' and driver data structure
'struct ffs_data' are bound to each other with cross-reference pointers
'ffs_data->private_data' and 'ffs_dev->ffs_data'. While the first one
is supposed to be valid through the whole life of 'struct ffs_data'
(and while 'struct ffs_dev' exists non-freed), the second one is cleared
in 'ffs_closed()' (called from 'ffs_data_reset()' or the last
'ffs_data_put()'). This can be called several times, alternating in
different order with 'ffs_free_inst()', that, if possible, clears
the other cross-reference.

As a result, different cases of these calls order may leave stale
cross-reference pointers, used when the pointed structure is already
freed. Even if it occasionally doesn't cause kernel crash, this error
is reported by KASAN-enabled kernel configuration.

For example, the case [last 'ffs_data_put()' - 'ffs_free_inst()'] was
fixed by commit cdafb6d8b8 ("usb: gadget: f_fs: Fix use-after-free in
ffs_free_inst").

The other case ['ffs_data_reset()' - 'ffs_free_inst()' - 'ffs_data_put()']
now causes KASAN reported error [1], when 'ffs_data_reset()' clears
'ffs_dev->ffs_data', then 'ffs_free_inst()' frees the 'struct ffs_dev',
but can't clear 'ffs_data->private_data', which is then accessed
in 'ffs_closed()' called from 'ffs_data_put()'. This happens since
'ffs_dev->ffs_data' reference is cleared too early.

Moreover, one more use case, when 'ffs_free_inst()' is called immediately
after mounting FunctionFS device (that is before the descriptors are
written and 'ffs_ready()' is called), and then 'ffs_data_reset()'
or 'ffs_data_put()' is called from accessing "ep0" file or unmounting
the device. This causes KASAN error report like [2], since
'ffs_dev->ffs_data' is not yet set when 'ffs_free_inst()' can't properly
clear 'ffs_data->private_data', that is later accessed to freed structure.

Fix these (and may be other) cases of stale pointers access by moving
setting and clearing of the mentioned cross-references to the single
places, setting both of them when 'struct ffs_data' is created and
bound to 'struct ffs_dev', and clearing both of them when one of the
structures is destroyed. It seems convenient to make this pointer
initialization and structures binding in 'ffs_acquire_dev()' and
make pointers clearing in 'ffs_release_dev()'. This required some
changes in these functions parameters and return types.

Also, 'ffs_release_dev()' calling requires some cleanup, fixing minor
issues, like (1) 'ffs_release_dev()' is not called if 'ffs_free_inst()'
is called without unmounting the device, and "release_dev" callback
is not called at all, or (2) "release_dev" callback is called before
"ffs_closed" callback on unmounting, which seems to be not correctly
nested with "acquire_dev" and "ffs_ready" callbacks.
Make this cleanup togther with other mentioned 'ffs_release_dev()' changes.

[1]
==================================================================
root@rcar-gen3:~# mkdir /dev/cfs
root@rcar-gen3:~# mkdir /dev/ffs
root@rcar-gen3:~# modprobe libcomposite
root@rcar-gen3:~# mount -t configfs none /dev/cfs
root@rcar-gen3:~# mkdir /dev/cfs/usb_gadget/g1
root@rcar-gen3:~# mkdir /dev/cfs/usb_gadget/g1/functions/ffs.ffs
[   64.340664] file system registered
root@rcar-gen3:~# mount -t functionfs ffs /dev/ffs
root@rcar-gen3:~# cd /dev/ffs
root@rcar-gen3:/dev/ffs# /home/root/ffs-test
ffs-test: info: ep0: writing descriptors (in v2 format)
[   83.181442] read descriptors
[   83.186085] read strings
ffs-test: info: ep0: writing strings
ffs-test: dbg:  ep1: starting
ffs-test: dbg:  ep2: starting
ffs-test: info: ep1: starts
ffs-test: info: ep2: starts
ffs-test: info: ep0: starts

^C
root@rcar-gen3:/dev/ffs# cd /home/root/
root@rcar-gen3:~# rmdir /dev/cfs/usb_gadget/g1/functions/ffs.ffs
[   98.935061] unloading
root@rcar-gen3:~# umount /dev/ffs
[  102.734301] ==================================================================
[  102.742059] BUG: KASAN: use-after-free in ffs_release_dev+0x64/0xa8 [usb_f_fs]
[  102.749683] Write of size 1 at addr ffff0004d46ff549 by task umount/2997
[  102.756709]
[  102.758311] CPU: 0 PID: 2997 Comm: umount Not tainted 5.13.0-rc4+ #8
[  102.764971] Hardware name: Renesas Salvator-X board based on r8a77951 (DT)
[  102.772179] Call trace:
[  102.774779]  dump_backtrace+0x0/0x330
[  102.778653]  show_stack+0x20/0x2c
[  102.782152]  dump_stack+0x11c/0x1ac
[  102.785833]  print_address_description.constprop.0+0x30/0x274
[  102.791862]  kasan_report+0x14c/0x1c8
[  102.795719]  __asan_report_store1_noabort+0x34/0x58
[  102.800840]  ffs_release_dev+0x64/0xa8 [usb_f_fs]
[  102.805801]  ffs_fs_kill_sb+0x50/0x84 [usb_f_fs]
[  102.810663]  deactivate_locked_super+0xa0/0xf0
[  102.815339]  deactivate_super+0x98/0xac
[  102.819378]  cleanup_mnt+0xd0/0x1b0
[  102.823057]  __cleanup_mnt+0x1c/0x28
[  102.826823]  task_work_run+0x104/0x180
[  102.830774]  do_notify_resume+0x458/0x14e0
[  102.835083]  work_pending+0xc/0x5f8
[  102.838762]
[  102.840357] Allocated by task 2988:
[  102.844032]  kasan_save_stack+0x28/0x58
[  102.848071]  kasan_set_track+0x28/0x3c
[  102.852016]  ____kasan_kmalloc+0x84/0x9c
[  102.856142]  __kasan_kmalloc+0x10/0x1c
[  102.860088]  __kmalloc+0x214/0x2f8
[  102.863678]  kzalloc.constprop.0+0x14/0x20 [usb_f_fs]
[  102.868990]  ffs_alloc_inst+0x8c/0x208 [usb_f_fs]
[  102.873942]  try_get_usb_function_instance+0xf0/0x164 [libcomposite]
[  102.880629]  usb_get_function_instance+0x64/0x68 [libcomposite]
[  102.886858]  function_make+0x128/0x1ec [libcomposite]
[  102.892185]  configfs_mkdir+0x330/0x590 [configfs]
[  102.897245]  vfs_mkdir+0x12c/0x1bc
[  102.900835]  do_mkdirat+0x180/0x1d0
[  102.904513]  __arm64_sys_mkdirat+0x80/0x94
[  102.908822]  invoke_syscall+0xf8/0x25c
[  102.912772]  el0_svc_common.constprop.0+0x150/0x1a0
[  102.917891]  do_el0_svc+0xa0/0xd4
[  102.921386]  el0_svc+0x24/0x34
[  102.924613]  el0_sync_handler+0xcc/0x154
[  102.928743]  el0_sync+0x198/0x1c0
[  102.932238]
[  102.933832] Freed by task 2996:
[  102.937144]  kasan_save_stack+0x28/0x58
[  102.941181]  kasan_set_track+0x28/0x3c
[  102.945128]  kasan_set_free_info+0x28/0x4c
[  102.949435]  ____kasan_slab_free+0x104/0x118
[  102.953921]  __kasan_slab_free+0x18/0x24
[  102.958047]  slab_free_freelist_hook+0x148/0x1f0
[  102.962897]  kfree+0x318/0x440
[  102.966123]  ffs_free_inst+0x164/0x2d8 [usb_f_fs]
[  102.971075]  usb_put_function_instance+0x84/0xa4 [libcomposite]
[  102.977302]  ffs_attr_release+0x18/0x24 [usb_f_fs]
[  102.982344]  config_item_put+0x140/0x1a4 [configfs]
[  102.987486]  configfs_rmdir+0x3fc/0x518 [configfs]
[  102.992535]  vfs_rmdir+0x114/0x234
[  102.996122]  do_rmdir+0x274/0x2b0
[  102.999617]  __arm64_sys_unlinkat+0x94/0xc8
[  103.004015]  invoke_syscall+0xf8/0x25c
[  103.007961]  el0_svc_common.constprop.0+0x150/0x1a0
[  103.013080]  do_el0_svc+0xa0/0xd4
[  103.016575]  el0_svc+0x24/0x34
[  103.019801]  el0_sync_handler+0xcc/0x154
[  103.023930]  el0_sync+0x198/0x1c0
[  103.027426]
[  103.029020] The buggy address belongs to the object at ffff0004d46ff500
[  103.029020]  which belongs to the cache kmalloc-128 of size 128
[  103.042079] The buggy address is located 73 bytes inside of
[  103.042079]  128-byte region [ffff0004d46ff500, ffff0004d46ff580)
[  103.054236] The buggy address belongs to the page:
[  103.059262] page:0000000021aa849b refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff0004d46fee00 pfn:0x5146fe
[  103.070437] head:0000000021aa849b order:1 compound_mapcount:0
[  103.076456] flags: 0x8000000000010200(slab|head|zone=2)
[  103.081948] raw: 8000000000010200 fffffc0013521a80 0000000d0000000d ffff0004c0002300
[  103.090052] raw: ffff0004d46fee00 000000008020001e 00000001ffffffff 0000000000000000
[  103.098150] page dumped because: kasan: bad access detected
[  103.103985]
[  103.105578] Memory state around the buggy address:
[  103.110602]  ffff0004d46ff400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  103.118161]  ffff0004d46ff480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  103.125726] >ffff0004d46ff500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  103.133284]                                               ^
[  103.139120]  ffff0004d46ff580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  103.146679]  ffff0004d46ff600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  103.154238] ==================================================================
[  103.161792] Disabling lock debugging due to kernel taint
[  103.167319] Unable to handle kernel paging request at virtual address 0037801d6000018e
[  103.175406] Mem abort info:
[  103.178457]   ESR = 0x96000004
[  103.181609]   EC = 0x25: DABT (current EL), IL = 32 bits
[  103.187020]   SET = 0, FnV = 0
[  103.190185]   EA = 0, S1PTW = 0
[  103.193417] Data abort info:
[  103.196385]   ISV = 0, ISS = 0x00000004
[  103.200315]   CM = 0, WnR = 0
[  103.203366] [0037801d6000018e] address between user and kernel address ranges
[  103.210611] Internal error: Oops: 96000004 [#1] PREEMPT SMP
[  103.216231] Modules linked in: usb_f_fs libcomposite configfs ath9k_htc led_class mac80211 libarc4 ath9k_common ath9k_hw ath cfg80211 aes_ce_blk sata_rc4
[  103.259233] CPU: 0 PID: 2997 Comm: umount Tainted: G    B             5.13.0-rc4+ #8
[  103.267031] Hardware name: Renesas Salvator-X board based on r8a77951 (DT)
[  103.273951] pstate: 00000005 (nzcv daif -PAN -UAO -TCO BTYPE=--)
[  103.280001] pc : ffs_data_clear+0x138/0x370 [usb_f_fs]
[  103.285197] lr : ffs_data_clear+0x124/0x370 [usb_f_fs]
[  103.290385] sp : ffff800014777a80
[  103.293725] x29: ffff800014777a80 x28: ffff0004d7649c80 x27: 0000000000000000
[  103.300931] x26: ffff800014777fb0 x25: ffff60009aec9394 x24: ffff0004d7649ca4
[  103.308136] x23: 1fffe0009a3d063a x22: dfff800000000000 x21: ffff0004d1e831d0
[  103.315340] x20: e1c000eb00000bb4 x19: ffff0004d1e83000 x18: 0000000000000000
[  103.322545] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[  103.329748] x14: 0720072007200720 x13: 0720072007200720 x12: 1ffff000012ef658
[  103.336952] x11: ffff7000012ef658 x10: 0720072007200720 x9 : ffff800011322648
[  103.344157] x8 : ffff800014777818 x7 : ffff80000977b2c7 x6 : 0000000000000000
[  103.351359] x5 : 0000000000000001 x4 : ffff7000012ef659 x3 : 0000000000000001
[  103.358562] x2 : 0000000000000000 x1 : 1c38001d6000018e x0 : e1c000eb00000c70
[  103.365766] Call trace:
[  103.368235]  ffs_data_clear+0x138/0x370 [usb_f_fs]
[  103.373076]  ffs_data_reset+0x20/0x304 [usb_f_fs]
[  103.377829]  ffs_data_closed+0x1ec/0x244 [usb_f_fs]
[  103.382755]  ffs_fs_kill_sb+0x70/0x84 [usb_f_fs]
[  103.387420]  deactivate_locked_super+0xa0/0xf0
[  103.391905]  deactivate_super+0x98/0xac
[  103.395776]  cleanup_mnt+0xd0/0x1b0
[  103.399299]  __cleanup_mnt+0x1c/0x28
[  103.402906]  task_work_run+0x104/0x180
[  103.406691]  do_notify_resume+0x458/0x14e0
[  103.410823]  work_pending+0xc/0x5f8
[  103.414351] Code: b4000a54 9102f280 12000802 d343fc01 (38f66821)
[  103.420490] ---[ end trace 57b43a50e8244f57 ]---
Segmentation fault
root@rcar-gen3:~#
==================================================================

[2]
==================================================================
root@rcar-gen3:~# mkdir /dev/ffs
root@rcar-gen3:~# modprobe libcomposite
root@rcar-gen3:~#
root@rcar-gen3:~# mount -t configfs none /dev/cfs
root@rcar-gen3:~# mkdir /dev/cfs/usb_gadget/g1
root@rcar-gen3:~# mkdir /dev/cfs/usb_gadget/g1/functions/ffs.ffs
[   54.766480] file system registered
root@rcar-gen3:~# mount -t functionfs ffs /dev/ffs
root@rcar-gen3:~# rmdir /dev/cfs/usb_gadget/g1/functions/ffs.ffs
[   63.197597] unloading
root@rcar-gen3:~# cat /dev/ffs/ep0
cat: read error:[   67.213506] ==================================================================
[   67.222095] BUG: KASAN: use-after-free in ffs_data_clear+0x70/0x370 [usb_f_fs]
[   67.229699] Write of size 1 at addr ffff0004c26e974a by task cat/2994
[   67.236446]
[   67.238045] CPU: 0 PID: 2994 Comm: cat Not tainted 5.13.0-rc4+ #8
[   67.244431] Hardware name: Renesas Salvator-X board based on r8a77951 (DT)
[   67.251624] Call trace:
[   67.254212]  dump_backtrace+0x0/0x330
[   67.258081]  show_stack+0x20/0x2c
[   67.261579]  dump_stack+0x11c/0x1ac
[   67.265260]  print_address_description.constprop.0+0x30/0x274
[   67.271286]  kasan_report+0x14c/0x1c8
[   67.275143]  __asan_report_store1_noabort+0x34/0x58
[   67.280265]  ffs_data_clear+0x70/0x370 [usb_f_fs]
[   67.285220]  ffs_data_reset+0x20/0x304 [usb_f_fs]
[   67.290172]  ffs_data_closed+0x240/0x244 [usb_f_fs]
[   67.295305]  ffs_ep0_release+0x40/0x54 [usb_f_fs]
[   67.300256]  __fput+0x304/0x580
[   67.303576]  ____fput+0x18/0x24
[   67.306893]  task_work_run+0x104/0x180
[   67.310846]  do_notify_resume+0x458/0x14e0
[   67.315154]  work_pending+0xc/0x5f8
[   67.318834]
[   67.320429] Allocated by task 2988:
[   67.324105]  kasan_save_stack+0x28/0x58
[   67.328144]  kasan_set_track+0x28/0x3c
[   67.332090]  ____kasan_kmalloc+0x84/0x9c
[   67.336217]  __kasan_kmalloc+0x10/0x1c
[   67.340163]  __kmalloc+0x214/0x2f8
[   67.343754]  kzalloc.constprop.0+0x14/0x20 [usb_f_fs]
[   67.349066]  ffs_alloc_inst+0x8c/0x208 [usb_f_fs]
[   67.354017]  try_get_usb_function_instance+0xf0/0x164 [libcomposite]
[   67.360705]  usb_get_function_instance+0x64/0x68 [libcomposite]
[   67.366934]  function_make+0x128/0x1ec [libcomposite]
[   67.372260]  configfs_mkdir+0x330/0x590 [configfs]
[   67.377320]  vfs_mkdir+0x12c/0x1bc
[   67.380911]  do_mkdirat+0x180/0x1d0
[   67.384589]  __arm64_sys_mkdirat+0x80/0x94
[   67.388899]  invoke_syscall+0xf8/0x25c
[   67.392850]  el0_svc_common.constprop.0+0x150/0x1a0
[   67.397969]  do_el0_svc+0xa0/0xd4
[   67.401464]  el0_svc+0x24/0x34
[   67.404691]  el0_sync_handler+0xcc/0x154
[   67.408819]  el0_sync+0x198/0x1c0
[   67.412315]
[   67.413909] Freed by task 2993:
[   67.417220]  kasan_save_stack+0x28/0x58
[   67.421257]  kasan_set_track+0x28/0x3c
[   67.425204]  kasan_set_free_info+0x28/0x4c
[   67.429513]  ____kasan_slab_free+0x104/0x118
[   67.434001]  __kasan_slab_free+0x18/0x24
[   67.438128]  slab_free_freelist_hook+0x148/0x1f0
[   67.442978]  kfree+0x318/0x440
[   67.446205]  ffs_free_inst+0x164/0x2d8 [usb_f_fs]
[   67.451156]  usb_put_function_instance+0x84/0xa4 [libcomposite]
[   67.457385]  ffs_attr_release+0x18/0x24 [usb_f_fs]
[   67.462428]  config_item_put+0x140/0x1a4 [configfs]
[   67.467570]  configfs_rmdir+0x3fc/0x518 [configfs]
[   67.472626]  vfs_rmdir+0x114/0x234
[   67.476215]  do_rmdir+0x274/0x2b0
[   67.479710]  __arm64_sys_unlinkat+0x94/0xc8
[   67.484108]  invoke_syscall+0xf8/0x25c
[   67.488055]  el0_svc_common.constprop.0+0x150/0x1a0
[   67.493175]  do_el0_svc+0xa0/0xd4
[   67.496671]  el0_svc+0x24/0x34
[   67.499896]  el0_sync_handler+0xcc/0x154
[   67.504024]  el0_sync+0x198/0x1c0
[   67.507520]
[   67.509114] The buggy address belongs to the object at ffff0004c26e9700
[   67.509114]  which belongs to the cache kmalloc-128 of size 128
[   67.522171] The buggy address is located 74 bytes inside of
[   67.522171]  128-byte region [ffff0004c26e9700, ffff0004c26e9780)
[   67.534328] The buggy address belongs to the page:
[   67.539355] page:000000003177a217 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5026e8
[   67.549175] head:000000003177a217 order:1 compound_mapcount:0
[   67.555195] flags: 0x8000000000010200(slab|head|zone=2)
[   67.560687] raw: 8000000000010200 fffffc0013037100 0000000c00000002 ffff0004c0002300
[   67.568791] raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
[   67.576890] page dumped because: kasan: bad access detected
[   67.582725]
[   67.584318] Memory state around the buggy address:
[   67.589343]  ffff0004c26e9600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   67.596903]  ffff0004c26e9680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   67.604463] >ffff0004c26e9700: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   67.612022]                                               ^
[   67.617860]  ffff0004c26e9780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   67.625421]  ffff0004c26e9800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   67.632981] ==================================================================
[   67.640535] Disabling lock debugging due to kernel taint
 File descriptor[   67.646100] Unable to handle kernel paging request at virtual address fabb801d4000018d
 in bad state
[   67.655456] Mem abort info:
[   67.659619]   ESR = 0x96000004
[   67.662801]   EC = 0x25: DABT (current EL), IL = 32 bits
[   67.668225]   SET = 0, FnV = 0
[   67.671375]   EA = 0, S1PTW = 0
[   67.674613] Data abort info:
[   67.677587]   ISV = 0, ISS = 0x00000004
[   67.681522]   CM = 0, WnR = 0
[   67.684588] [fabb801d4000018d] address between user and kernel address ranges
[   67.691849] Internal error: Oops: 96000004 [#1] PREEMPT SMP
[   67.697470] Modules linked in: usb_f_fs libcomposite configfs ath9k_htc led_class mac80211 libarc4 ath9k_common ath9k_hw ath cfg80211 aes_ce_blk crypto_simd cryptd aes_ce_cipher ghash_ce gf128mul sha2_ce sha1_ce evdev sata_rcar libata xhci_plat_hcd scsi_mod xhci_hcd rene4
[   67.740467] CPU: 0 PID: 2994 Comm: cat Tainted: G    B             5.13.0-rc4+ #8
[   67.748005] Hardware name: Renesas Salvator-X board based on r8a77951 (DT)
[   67.754924] pstate: 00000005 (nzcv daif -PAN -UAO -TCO BTYPE=--)
[   67.760974] pc : ffs_data_clear+0x138/0x370 [usb_f_fs]
[   67.766178] lr : ffs_data_clear+0x124/0x370 [usb_f_fs]
[   67.771365] sp : ffff800014767ad0
[   67.774706] x29: ffff800014767ad0 x28: ffff800009cf91c0 x27: ffff0004c54861a0
[   67.781913] x26: ffff0004dc90b288 x25: 1fffe00099ec10f5 x24: 00000000000a801d
[   67.789118] x23: 1fffe00099f6953a x22: dfff800000000000 x21: ffff0004cfb4a9d0
[   67.796322] x20: d5e000ea00000bb1 x19: ffff0004cfb4a800 x18: 0000000000000000
[   67.803526] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[   67.810730] x14: 0720072007200720 x13: 0720072007200720 x12: 1ffff000028ecefa
[   67.817934] x11: ffff7000028ecefa x10: 0720072007200720 x9 : ffff80001132c014
[   67.825137] x8 : ffff8000147677d8 x7 : ffff8000147677d7 x6 : 0000000000000000
[   67.832341] x5 : 0000000000000001 x4 : ffff7000028ecefb x3 : 0000000000000001
[   67.839544] x2 : 0000000000000005 x1 : 1abc001d4000018d x0 : d5e000ea00000c6d
[   67.846748] Call trace:
[   67.849218]  ffs_data_clear+0x138/0x370 [usb_f_fs]
[   67.854058]  ffs_data_reset+0x20/0x304 [usb_f_fs]
[   67.858810]  ffs_data_closed+0x240/0x244 [usb_f_fs]
[   67.863736]  ffs_ep0_release+0x40/0x54 [usb_f_fs]
[   67.868488]  __fput+0x304/0x580
[   67.871665]  ____fput+0x18/0x24
[   67.874837]  task_work_run+0x104/0x180
[   67.878622]  do_notify_resume+0x458/0x14e0
[   67.882754]  work_pending+0xc/0x5f8
[   67.886282] Code: b4000a54 9102f280 12000802 d343fc01 (38f66821)
[   67.892422] ---[ end trace 6d7cedf53d7abbea ]---
Segmentation fault
root@rcar-gen3:~#
==================================================================

Fixes: 4b187fceec ("usb: gadget: FunctionFS: add devices management code")
Fixes: 3262ad8243 ("usb: gadget: f_fs: Stop ffs_closed NULL pointer dereference")
Fixes: cdafb6d8b8 ("usb: gadget: f_fs: Fix use-after-free in ffs_free_inst")
Reported-by: Bhuvanesh Surachari <bhuvanesh_surachari@mentor.com>
Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Reviewed-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
Link: https://lore.kernel.org/r/20210603171507.22514-1-andrew_gabbasov@mentor.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-09 11:24:09 +02:00
Wesley Cheng 6fc1db5e62 usb: gadget: f_fs: Ensure io_completion_wq is idle during unbind
During unbind, ffs_func_eps_disable() will be executed, resulting in
completion callbacks for any pending USB requests.  When using AIO,
irrespective of the completion status, io_data work is queued to
io_completion_wq to evaluate and handle the completed requests.  Since
work runs asynchronously to the unbind() routine, there can be a
scenario where the work runs after the USB gadget has been fully
removed, resulting in accessing of a resource which has been already
freed. (i.e. usb_ep_free_request() accessing the USB ep structure)

Explicitly drain the io_completion_wq, instead of relying on the
destroy_workqueue() (in ffs_data_put()) to make sure no pending
completion work items are running.

Signed-off-by: Wesley Cheng <wcheng@codeaurora.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1621644261-1236-1-git-send-email-wcheng@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-04 13:40:46 +02:00
kernel test robot 423432072d USB: gadget: f_fs: fix memdup_user.cocci warnings
drivers/usb/gadget/function/f_fs.c:3829:8-15: WARNING opportunity for memdup_user

 Use memdup_user rather than duplicating its implementation
 This is a little bit restricted to reduce false positives

Generated by: scripts/coccinelle/api/memdup_user.cocci

Fixes: 8704fd73bf ("USB: gadget: f_fs: remove likely/unlikely")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/20210308070951.GA83949@8a16bdd473dc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23 15:24:26 +01:00
Dean Anderson 55b74ce7d2 usb: gadget/function/f_fs string table fix for multiple languages
Fixes bug with the handling of more than one language in
the string table in f_fs.c.
str_count was not reset for subsequent language codes.
str_count-- "rolls under" and processes u32 max strings on
the processing of the second language entry.
The existing bug can be reproduced by adding a second language table
to the structure "strings" in tools/usb/ffs-test.c.

Signed-off-by: Dean Anderson <dean@sensoray.com>
Link: https://lore.kernel.org/r/20210317224109.21534-1-dean@sensoray.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23 12:50:03 +01:00
Greg Kroah-Hartman 8704fd73bf USB: gadget: f_fs: remove likely/unlikely
They are used way too often in this file, in some ways that are actually
wrong.  Almost all of these are already known by the compiler and CPU so
just remove them all as none of these should be on any "hot paths" where
it actually matters.

Cc: Felipe Balbi <balbi@kernel.org>
Reported-by: Peter Chen <peter.chen@nxp.com>
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Link: https://lore.kernel.org/r/20201127140559.381351-6-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-10 16:14:34 +01:00
Jack Pham a353397b0d usb: gadget: f_fs: Re-use SS descriptors for SuperSpeedPlus
In many cases a function that supports SuperSpeed can very well
operate in SuperSpeedPlus, if a gadget controller supports it,
as the endpoint descriptors (and companion descriptors) are
generally identical and can be re-used. This is true for two
commonly used functions: Android's ADB and MTP. So we can simply
assign the usb_function's ssp_descriptors array to point to its
ss_descriptors, if available. Similarly, we need to allow an
epfile's ioctl for FUNCTIONFS_ENDPOINT_DESC to correctly
return the corresponding SuperSpeed endpoint descriptor in case
the connected speed is SuperSpeedPlus as well.

The only exception is if a function wants to implement an
Isochronous endpoint capable of transferring more than 48KB per
service interval when operating at greater than USB 3.1 Gen1
speed, in which case it would require an additional SuperSpeedPlus
Isochronous Endpoint Companion descriptor to be returned as part
of the Configuration Descriptor. Support for that would need
to be separately added to the userspace-facing FunctionFS API
which may not be a trivial task--likely a new descriptor format
(v3?) may need to be devised to allow for separate SS and SSP
descriptors to be supplied.

Signed-off-by: Jack Pham <jackp@codeaurora.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201027230731.9073-1-jackp@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-10 16:12:25 +01:00
Greg Kroah-Hartman 93837812a5 Merge 5.10-rc7 into usb-next
We want the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-07 10:20:51 +01:00
Vamsi Krishna Samavedam a4b98a7512 usb: gadget: f_fs: Use local copy of descriptors for userspace copy
The function may be unbound causing the ffs_ep and its descriptors
to be freed while userspace is in the middle of an ioctl requesting
the same descriptors. Avoid dangling pointer reference by first
making a local copy of desctiptors before releasing the spinlock.

Fixes: c559a35341 ("usb: gadget: f_fs: add ioctl returning ep descriptor")
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Vamsi Krishna Samavedam <vskrishn@codeaurora.org>
Signed-off-by: Jack Pham <jackp@codeaurora.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201130203453.28154-1-jackp@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-04 16:09:10 +01:00
Gustavo A. R. Silva 93c747ed00 usb: Fix fall-through warnings for Clang
In preparation to enable -Wimplicit-fallthrough for Clang, fix multiple
warnings by explicitly adding multiple break/return/fallthrough
statements instead of letting the code fall through to the next
case.

Link: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/a76da7ca5b4f41c13d27b298accb8222d0b04e61.1605896060.git.gustavoars@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-23 17:46:01 +01:00
Gustavo A. R. Silva a74005ab91 usb: gadget: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200707171500.GA13620@embeddedor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-10 08:55:18 +02:00
Lee Jones 8f9a0e1005 usb: gadget: function: f_fs: Demote function header which is clearly not kerneldoc
No attempt has been made to document the demoted function here.

Fixes the following W=1 kernel build warning(s):

 drivers/usb/gadget/function/f_fs.c:2361: warning: Function parameter or member 'type' not described in '__ffs_data_do_os_desc'
 drivers/usb/gadget/function/f_fs.c:2361: warning: Function parameter or member 'h' not described in '__ffs_data_do_os_desc'
 drivers/usb/gadget/function/f_fs.c:2361: warning: Function parameter or member 'data' not described in '__ffs_data_do_os_desc'
 drivers/usb/gadget/function/f_fs.c:2361: warning: Function parameter or member 'len' not described in '__ffs_data_do_os_desc'
 drivers/usb/gadget/function/f_fs.c:2361: warning: Function parameter or member 'priv' not described in '__ffs_data_do_os_desc'

Cc: Felipe Balbi <balbi@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20200706133341.476881-12-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-09 17:19:57 +02:00
Christoph Hellwig 37c54f9bd4 kernel: set USER_DS in kthread_use_mm
Some architectures like arm64 and s390 require USER_DS to be set for
kernel threads to access user address space, which is the whole purpose of
kthread_use_mm, but other like x86 don't.  That has lead to a huge mess
where some callers are fixed up once they are tested on said
architectures, while others linger around and yet other like io_uring try
to do "clever" optimizations for what usually is just a trivial asignment
to a member in the thread_struct for most architectures.

Make kthread_use_mm set USER_DS, and kthread_unuse_mm restore to the
previous value instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: http://lkml.kernel.org/r/20200404094101.672954-7-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-10 19:14:18 -07:00
Christoph Hellwig f5678e7f2a kernel: better document the use_mm/unuse_mm API contract
Switch the function documentation to kerneldoc comments, and add
WARN_ON_ONCE asserts that the calling thread is a kernel thread and does
not have ->mm set (or has ->mm set in the case of unuse_mm).

Also give the functions a kthread_ prefix to better document the use case.

[hch@lst.de: fix a comment typo, cover the newly merged use_mm/unuse_mm caller in vfio]
  Link: http://lkml.kernel.org/r/20200416053158.586887-3-hch@lst.de
[sfr@canb.auug.org.au: powerpc/vas: fix up for {un}use_mm() rename]
  Link: http://lkml.kernel.org/r/20200422163935.5aa93ba5@canb.auug.org.au

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [usb]
Acked-by: Haren Myneni <haren@linux.ibm.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Link: http://lkml.kernel.org/r/20200404094101.672954-6-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-10 19:14:18 -07:00
Christoph Hellwig 9bf5b9eb23 kernel: move use_mm/unuse_mm to kthread.c
Patch series "improve use_mm / unuse_mm", v2.

This series improves the use_mm / unuse_mm interface by better documenting
the assumptions, and my taking the set_fs manipulations spread over the
callers into the core API.

This patch (of 3):

Use the proper API instead.

Link: http://lkml.kernel.org/r/20200404094101.672954-1-hch@lst.de

These helpers are only for use with kernel threads, and I will tie them
more into the kthread infrastructure going forward.  Also move the
prototypes to kthread.h - mmu_context.h was a little weird to start with
as it otherwise contains very low-level MM bits.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: http://lkml.kernel.org/r/20200404094101.672954-1-hch@lst.de
Link: http://lkml.kernel.org/r/20200416053158.586887-1-hch@lst.de
Link: http://lkml.kernel.org/r/20200404094101.672954-5-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-10 19:14:18 -07:00
Jason Yan a54177d2dc usb: gadget: f_fs: remove unneeded semicolon in __ffs_data_got_descs()
Fix the following coccicheck warning:

drivers/usb/gadget/function/f_fs.c:2507:2-3: Unneeded semicolon

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
2020-05-25 11:09:38 +03:00
Udipto Goswami 1c2e54fbf1 usb: f_fs: Clear OS Extended descriptor counts to zero in ffs_data_reset()
For userspace functions using OS Descriptors, if a function also supplies
Extended Property descriptors currently the counts and lengths stored in
the ms_os_descs_ext_prop_{count,name_len,data_len} variables are not
getting reset to 0 during an unbind or when the epfiles are closed. If
the same function is re-bound and the descriptors are re-written, this
results in those count/length variables to monotonically increase
causing the VLA allocation in _ffs_func_bind() to grow larger and larger
at each bind/unbind cycle and eventually fail to allocate.

Fix this by clearing the ms_os_descs_ext_prop count & lengths to 0 in
ffs_data_reset().

Fixes: f0175ab519 ("usb: gadget: f_fs: OS descriptors support")
Cc: stable@vger.kernel.org
Signed-off-by: Udipto Goswami <ugoswami@codeaurora.org>
Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>
Reviewed-by: Manu Gautam <mgautam@codeaurora.org>
Link: https://lore.kernel.org/r/20200402044521.9312-1-sallenki@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-16 14:59:49 +02:00
Linus Torvalds 4b9fd8a829 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Continued user-access cleanups in the futex code.

   - percpu-rwsem rewrite that uses its own waitqueue and atomic_t
     instead of an embedded rwsem. This addresses a couple of
     weaknesses, but the primary motivation was complications on the -rt
     kernel.

   - Introduce raw lock nesting detection on lockdep
     (CONFIG_PROVE_RAW_LOCK_NESTING=y), document the raw_lock vs. normal
     lock differences. This too originates from -rt.

   - Reuse lockdep zapped chain_hlocks entries, to conserve RAM
     footprint on distro-ish kernels running into the "BUG:
     MAX_LOCKDEP_CHAIN_HLOCKS too low!" depletion of the lockdep
     chain-entries pool.

   - Misc cleanups, smaller fixes and enhancements - see the changelog
     for details"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (55 commits)
  fs/buffer: Make BH_Uptodate_Lock bit_spin_lock a regular spinlock_t
  thermal/x86_pkg_temp: Make pkg_temp_lock a raw_spinlock_t
  Documentation/locking/locktypes: Minor copy editor fixes
  Documentation/locking/locktypes: Further clarifications and wordsmithing
  m68knommu: Remove mm.h include from uaccess_no.h
  x86: get rid of user_atomic_cmpxchg_inatomic()
  generic arch_futex_atomic_op_inuser() doesn't need access_ok()
  x86: don't reload after cmpxchg in unsafe_atomic_op2() loop
  x86: convert arch_futex_atomic_op_inuser() to user_access_begin/user_access_end()
  objtool: whitelist __sanitizer_cov_trace_switch()
  [parisc, s390, sparc64] no need for access_ok() in futex handling
  sh: no need of access_ok() in arch_futex_atomic_op_inuser()
  futex: arch_futex_atomic_op_inuser() calling conventions change
  completion: Use lockdep_assert_RT_in_threaded_ctx() in complete_all()
  lockdep: Add posixtimer context tracing bits
  lockdep: Annotate irq_work
  lockdep: Add hrtimer context tracing bits
  lockdep: Introduce wait-type checks
  completion: Use simple wait queues
  sched/swait: Prepare usage in completions
  ...
2020-03-30 16:17:15 -07:00
Sriharsha Allenki f63ec55ff9 usb: gadget: f_fs: Fix use after free issue as part of queue failure
In AIO case, the request is freed up if ep_queue fails.
However, io_data->req still has the reference to this freed
request. In the case of this failure if there is aio_cancel
call on this io_data it will lead to an invalid dequeue
operation and a potential use after free issue.
Fix this by setting the io_data->req to NULL when the request
is freed as part of queue failure.

Fixes: 2e4c7553cd ("usb: gadget: f_fs: add aio support")
Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>
CC: stable <stable@vger.kernel.org>
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Link: https://lore.kernel.org/r/20200326115620.12571-1-sallenki@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-26 15:05:44 +01:00
Thomas Gleixner a5c6234e10 completion: Use simple wait queues
completion uses a wait_queue_head_t to enqueue waiters.

wait_queue_head_t contains a spinlock_t to protect the list of waiters
which excludes it from being used in truly atomic context on a PREEMPT_RT
enabled kernel.

The spinlock in the wait queue head cannot be replaced by a raw_spinlock
because:

  - wait queues can have custom wakeup callbacks, which acquire other
    spinlock_t locks and have potentially long execution times

  - wake_up() walks an unbounded number of list entries during the wake up
    and may wake an unbounded number of waiters.

For simplicity and performance reasons complete() should be usable on
PREEMPT_RT enabled kernels.

completions do not use custom wakeup callbacks and are usually single
waiter, except for a few corner cases.

Replace the wait queue in the completion with a simple wait queue (swait),
which uses a raw_spinlock_t for protecting the waiter list and therefore is
safe to use inside truly atomic regions on PREEMPT_RT.

There is no semantical or functional change:

  - completions use the exclusive wait mode which is what swait provides

  - complete() wakes one exclusive waiter

  - complete_all() wakes all waiters while holding the lock which protects
    the wait queue against newly incoming waiters. The conversion to swait
    preserves this behaviour.

complete_all() might cause unbound latencies with a large number of waiters
being woken at once, but most complete_all() usage sites are either in
testing or initialization code or have only a really small number of
concurrent waiters which for now does not cause a latency problem. Keep it
simple for now.

The fixup of the warning check in the USB gadget driver is just a straight
forward conversion of the lockless waiter check from one waitqueue type to
the other.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/20200321113242.317954042@linutronix.de
2020-03-21 16:00:24 +01:00