linux.git/drivers/usb/gadget/function/f_fs.c, branch v5.5

treewide: Use sizeof_field() macro

2019-12-09T18:36:44+00:00

Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except
at places where these are defined. Later patches will remove the unused
definition of FIELD_SIZEOF().

This patch is generated using following script:

EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h"

git grep -l -e "\bFIELD_SIZEOF\b" | while read file;
do

	if [[ "$file" =~ $EXCLUDE_FILES ]]; then
		continue
	fi
	sed -i  -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file;
done

Signed-off-by: Pankaj Bharadiya 
Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com
Co-developed-by: Kees Cook 
Signed-off-by: Kees Cook 
Acked-by: David Miller  # for net

compat_ioctl: use correct compat_ptr() translation in drivers

2019-10-23T15:23:44+00:00

A handful of drivers all have a trivial wrapper around their ioctl
handler, but don't call the compat_ptr() conversion function at the
moment. In practice this does not matter, since none of them are used
on the s390 architecture and for all other architectures, compat_ptr()
does not do anything, but using the new compat_ptr_ioctl()
helper makes it more correct in theory, and simplifies the code.

I checked that all ioctl handlers in these files are compatible
and take either pointer arguments or no argument.

Acked-by: Al Viro 
Acked-by: Greg Kroah-Hartman 
Acked-by: Andrew Donnellan 
Acked-by: Felipe Balbi 
Signed-off-by: Arnd Bergmann

vfs: Convert functionfs to use the new mount API

2019-09-19T02:35:43+00:00

Convert the functionfs filesystem to the new internal mount API as the old
one will be obsoleted and removed.  This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

Signed-off-by: David Howells 
Acked-by: Felipe Balbi 
Acked-by: Michal Nazarewicz 
cc: linux-usb@vger.kernel.org
Signed-off-by: Al Viro

usb: gadget: Zero ffs_io_data

2019-06-18T08:58:29+00:00

In some cases the "Allocate & copy" block in ffs_epfile_io() is not
executed. Consequently, in such a case ffs_alloc_buffer() is never called
and struct ffs_io_data is not initialized properly. This in turn leads to
problems when ffs_free_buffer() is called at the end of ffs_epfile_io().

This patch uses kzalloc() instead of kmalloc() in the aio case and memset()
in non-aio case to properly initialize struct ffs_io_data.

Signed-off-by: Andrzej Pietrasiewicz 
Signed-off-by: Felipe Balbi

usb: gadget: f_fs: data_len used before properly set

2019-06-18T08:58:28+00:00

The following line of code in function ffs_epfile_io is trying to set
flag io_data->use_sg in case buffer required is larger than one page.

    io_data->use_sg = gadget->sg_supported && data_len > PAGE_SIZE;

However at this point of time the variable data_len has not been set
to the proper buffer size yet. The consequence is that io_data->use_sg
is always set regardless what buffer size really is, because the condition
(data_len > PAGE_SIZE) is effectively an unsigned comparison between
-EINVAL and PAGE_SIZE which would always result in TRUE.

Fixes: 772a7a724f69 ("usb: gadget: f_fs: Allow scatter-gather buffers")
Signed-off-by: Fei Yang 
Cc: stable 
Signed-off-by: Felipe Balbi

usb: gadget: f_fs: don't free buffer prematurely

2019-05-03T06:12:53+00:00

The following kernel panic happens due to the io_data buffer gets deallocated
before the async io is completed. Add a check for the case where io_data buffer
should be deallocated by ffs_user_copy_worker.

[   41.663334] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
[   41.672099] #PF error: [normal kernel read fault]
[   41.677356] PGD 20c974067 P4D 20c974067 PUD 20c973067 PMD 0
[   41.683687] Oops: 0000 [#1] PREEMPT SMP
[   41.687976] CPU: 1 PID: 7 Comm: kworker/u8:0 Tainted: G     U            5.0.0-quilt-2e5dc0ac-00790-gd8c79f2-dirty #2
[   41.705309] Workqueue: adb ffs_user_copy_worker
[   41.705316] RIP: 0010:__vunmap+0x2a/0xc0
[   41.705318] Code: 0f 1f 44 00 00 48 85 ff 0f 84 87 00 00 00 55 f7 c7 ff 0f 00 00 48 89 e5 41 55 41 89 f5 41 54 53 48 89 fb 75 71 e8 56 d7 ff ff <4c> 8b 60 48 4d 85 e4 74 76 48 89 df e8 25 ff ff ff 45 85 ed 74 46
[   41.705320] RSP: 0018:ffffbc3a40053df0 EFLAGS: 00010286
[   41.705322] RAX: 0000000000000000 RBX: ffffbc3a406f1000 RCX: 0000000000000000
[   41.705323] RDX: 0000000000000001 RSI: 0000000000000001 RDI: 00000000ffffffff
[   41.705324] RBP: ffffbc3a40053e08 R08: 000000000001fb79 R09: 0000000000000037
[   41.705325] R10: ffffbc3a40053b68 R11: ffffbc3a40053cad R12: fffffffffffffff2
[   41.705326] R13: 0000000000000001 R14: 0000000000000000 R15: ffffffffffffffff
[   41.705328] FS:  0000000000000000(0000) GS:ffff9e2977a80000(0000) knlGS:0000000000000000
[   41.705329] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   41.705330] CR2: 0000000000000048 CR3: 000000020c994000 CR4: 00000000003406e0
[   41.705331] Call Trace:
[   41.705338]  vfree+0x50/0xb0
[   41.705341]  ffs_user_copy_worker+0xe9/0x1c0
[   41.705344]  process_one_work+0x19f/0x3e0
[   41.705348]  worker_thread+0x3f/0x3b0
[   41.829766]  kthread+0x12b/0x150
[   41.833371]  ? process_one_work+0x3e0/0x3e0
[   41.838045]  ? kthread_create_worker_on_cpu+0x70/0x70
[   41.843695]  ret_from_fork+0x3a/0x50
[   41.847689] Modules linked in: hci_uart bluetooth ecdh_generic rfkill_gpio dwc3_pci dwc3 snd_usb_audio mei_me tpm_crb snd_usbmidi_lib xhci_pci xhci_hcd mei tpm snd_hwdep cfg80211 snd_soc_skl snd_soc_skl_ipc snd_soc_sst_ipc snd_soc_sst_dsp snd_hda_ext_core snd_hda_core videobuf2_dma_sg crlmodule
[   41.876880] CR2: 0000000000000048
[   41.880584] ---[ end trace 2bc4addff0f2e673 ]---
[   41.891346] RIP: 0010:__vunmap+0x2a/0xc0
[   41.895734] Code: 0f 1f 44 00 00 48 85 ff 0f 84 87 00 00 00 55 f7 c7 ff 0f 00 00 48 89 e5 41 55 41 89 f5 41 54 53 48 89 fb 75 71 e8 56 d7 ff ff <4c> 8b 60 48 4d 85 e4 74 76 48 89 df e8 25 ff ff ff 45 85 ed 74 46
[   41.916740] RSP: 0018:ffffbc3a40053df0 EFLAGS: 00010286
[   41.922583] RAX: 0000000000000000 RBX: ffffbc3a406f1000 RCX: 0000000000000000
[   41.930563] RDX: 0000000000000001 RSI: 0000000000000001 RDI: 00000000ffffffff
[   41.938540] RBP: ffffbc3a40053e08 R08: 000000000001fb79 R09: 0000000000000037
[   41.946520] R10: ffffbc3a40053b68 R11: ffffbc3a40053cad R12: fffffffffffffff2
[   41.954502] R13: 0000000000000001 R14: 0000000000000000 R15: ffffffffffffffff
[   41.962482] FS:  0000000000000000(0000) GS:ffff9e2977a80000(0000) knlGS:0000000000000000
[   41.971536] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   41.977960] CR2: 0000000000000048 CR3: 000000020c994000 CR4: 00000000003406e0
[   41.985930] Kernel panic - not syncing: Fatal exception
[   41.991817] Kernel Offset: 0x16000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[   42.009525] Rebooting in 10 seconds..
[   52.014376] ACPI MEMORY or I/O RESET_REG.

Fixes: 772a7a724f69 ("usb: gadget: f_fs: Allow scatter-gather buffers")
Signed-off-by: Fei Yang 
Reviewed-by: Manu Gautam 
Tested-by: John Stultz 
Signed-off-by: Felipe Balbi

usb: f_fs: Avoid crash due to out-of-scope stack ptr access

2019-02-11T09:11:29+00:00

Since the 5.0 merge window opened, I've been seeing frequent
crashes on suspend and reboot with the trace:

[   36.911170] Unable to handle kernel paging request at virtual address ffffff801153d660
[   36.912769] Unable to handle kernel paging request at virtual address ffffff800004b564
...
[   36.950666] Call trace:
[   36.950670]  queued_spin_lock_slowpath+0x1cc/0x2c8
[   36.950681]  _raw_spin_lock_irqsave+0x64/0x78
[   36.950692]  complete+0x28/0x70
[   36.950703]  ffs_epfile_io_complete+0x3c/0x50
[   36.950713]  usb_gadget_giveback_request+0x34/0x108
[   36.950721]  dwc3_gadget_giveback+0x50/0x68
[   36.950723]  dwc3_thread_interrupt+0x358/0x1488
[   36.950731]  irq_thread_fn+0x30/0x88
[   36.950734]  irq_thread+0x114/0x1b0
[   36.950739]  kthread+0x104/0x130
[   36.950747]  ret_from_fork+0x10/0x1c

I isolated this down to in ffs_epfile_io():
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/usb/gadget/function/f_fs.c#n1065

Where the completion done is setup on the stack:
  DECLARE_COMPLETION_ONSTACK(done);

Then later we setup a request and queue it, and wait for it:
  if (unlikely(wait_for_completion_interruptible(&done))) {
    /*
    * To avoid race condition with ffs_epfile_io_complete,
    * dequeue the request first then check
    * status. usb_ep_dequeue API should guarantee no race
    * condition with req->complete callback.
    */
    usb_ep_dequeue(ep->ep, req);
    interrupted = ep->status < 0;
  }

The problem is, that we end up being interrupted, dequeue the
request, and exit.

But then the irq triggers and we try calling complete() on the
context pointer which points to now random stack space, which
results in the panic.

Alan Stern pointed out there is a bug here, in that the snippet
above "assumes that usb_ep_dequeue() waits until the request has
been completed." And that:

    wait_for_completion(&done);

Is needed right after the usb_ep_dequeue().

Thus this patch implements that change. With it I no longer see
the crashes on suspend or reboot.

This issue seems to have been uncovered by behavioral changes in
the dwc3 driver in commit fec9095bdef4e ("usb: dwc3: gadget:
remove wait_end_transfer").

Cc: Alan Stern 
Cc: Felipe Balbi 
Cc: Zeng Tao 
Cc: Jack Pham 
Cc: Thinh Nguyen 
Cc: Chen Yu 
Cc: Jerry Zhang 
Cc: Lars-Peter Clausen 
Cc: Vincent Pelletier 
Cc: Andrzej Pietrasiewicz 
Cc: Greg Kroah-Hartman 
Cc: Linux USB List 
Suggested-by: Alan Stern 
Signed-off-by: John Stultz 
Signed-off-by: Felipe Balbi

usb: gadget: f_fs: preserve wMaxPacketSize across usb_ep_autoconfig() call

2019-02-07T11:14:51+00:00

usb_ep_autoconfig() treats the passed descriptor as if it were an fs
descriptor. In particular, for bulk endpoints, it clips wMaxPacketSize
to 64. This patch preserves the original value.

Signed-off-by: Andrzej Pietrasiewicz 
Signed-off-by: Felipe Balbi

usb: gadget: f_fs: Allow scatter-gather buffers

2018-11-26T07:06:32+00:00

Some protocols implemented in userspace with FunctionFS might require large
buffers, e.g. 64kB or more. Currently the said memory is allocated with
kmalloc, which might fail should system memory be highly fragmented.

On the other hand, some UDC hardware allows scatter-gather operation and
this patch takes advantage of this capability: if the requested buffer
is larger than PAGE_SIZE and the UDC allows scatter-gather operation, then
the buffer is allocated with vmalloc and a scatterlist describing it is
created and passed to usb request.

Signed-off-by: Andrzej Pietrasiewicz 
Signed-off-by: Felipe Balbi

usb: gadget: f_fs: Add support for CCID descriptors.

2018-11-26T07:06:32+00:00

Nothing to remap, only check length.
Define a minimal structure for CCID descriptor only used to check length.
As this descriptor shares the same value as HID descriptors, keep track and
compare current interface's class to expected HID and CCID standard values.

Signed-off-by: Vincent Pelletier 
Signed-off-by: Felipe Balbi