DTV_ISDBT_LAYER_ENABLED parameter should be set to "All" by default,
instead of "None", as described in the API document.
Signed-off-by: NAkihiro Tsukada <tskd08@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab+samsung@kernel.org>

As warned by smatch:
	drivers/media/dvb-core/dvb_frontend.c:314 dvb_frontend_get_event() warn: inconsistent returns 'sem:&fepriv->sem'.
	  Locked on:   line 288
	               line 295
	               line 306
	               line 314
	  Unlocked on: line 303

The lock implementation for get event is wrong, as, if an
interrupt occurs, down_interruptible() will fail, and the
routine will call up() twice when userspace calls the ioctl
again.

The bad code is there since when Linux migrated to git, in
2005.

Cc: stable@vger.kernel.org
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

FE_GET_PROPERTY has always failed as following situations:
  - Use compatible ioctl
  - The array of 'struct dtv_property' has 2 or more items

This patch fixes wrong cast to a pointer 'struct dtv_property' from a
pointer of 2nd or after item of 'struct compat_dtv_property' array.
Signed-off-by: NKatsuhiro Suzuki <suzuki.katsuhiro@socionext.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Solves those warnings:
	drivers/media/dvb-core/dvb_frontend.c:2297:39: warning: incorrect type in argument 1 (different address spaces)
	drivers/media/dvb-core/dvb_frontend.c:2297:39:    expected void const [noderef] <asn:1>*<noident>
	drivers/media/dvb-core/dvb_frontend.c:2297:39:    got struct dtv_property *props
	drivers/media/dvb-core/dvb_frontend.c:2331:39: warning: incorrect type in argument 1 (different address spaces)
	drivers/media/dvb-core/dvb_frontend.c:2331:39:    expected void const [noderef] <asn:1>*<noident>
	drivers/media/dvb-core/dvb_frontend.c:2331:39:    got struct dtv_property *props

No functional changes.
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.
Scripted-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Except for DVB, all media kAPI headers are at include/media.

Move the headers to it.
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

This commit adds a new property DTV_SCRAMBLING_SEQUENCE_INDEX.

This 18 bit field, when present, carries the index of the DVB-S2 physical
layer scrambling sequence as defined in clause 5.5.4 of EN 302 307.
There is no explicit signalling method to convey scrambling sequence index
to the receiver. If S2 satellite delivery system descriptor is available
it can be used to read the scrambling sequence index (EN 300 468 table 41).

By default, gold scrambling sequence index 0 is used. The valid scrambling
sequence index range is from 0 to 262142.

Increase the DVB API version in order userspace to be aware of the changes.
Signed-off-by: NAthanasios Oikonomou <athoik@gmail.com>
Acked-by: NRalph Metzler <rjkm@metzlerbros.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

The dtv_properties structure and the dtv_property structure are
different sizes in 32-bit and 64-bit system. This patch provides
FE_SET_PROPERTY and FE_GET_PROPERTY ioctl commands implementation for
32-bit user space applications.
Signed-off-by: NJaedon Shin <jaedon.shin@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Adds compat_ioctl for 32-bit user space applications on a 64-bit system.

[m.chehab@osg.samsung.com: add missing include compat.h]
Signed-off-by: NJaedon Shin <jaedon.shin@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Adds unlocked ioctl function directly in dvb_frontend.c instead of using
dvb_generic_ioctl().
Signed-off-by: NJaedon Shin <jaedon.shin@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/dvb-core/dvb_frontend.c:154:2-7: WARNING: NULL check before freeing functions like kfree, debugfs_remove, debugfs_remove_recursive or usb_free_urb is not needed. Maybe consider reorganizing relevant code to avoid passing NULL values.

 NULL check before some freeing functions is not needed.

 Based on checkpatch warning
 "kfree(NULL) is safe this check is probably not required"
 and kfreeaddr.cocci by Julia Lawall.

Generated by: scripts/coccinelle/free/ifnullfree.cocci

Fixes: b1cb7372 ("dvb_frontend: don't use-after-free the frontend struct")
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

The correct error code when a function is not defined is
-ENOTSUPP. It was typoed wrong as -EOPNOTSUPP, with,
unfortunately, exists, but it is not used by the DVB core.

Thanks-to: Geert Uytterhoeven <geert@linux-m68k.org>
Thanks-to: Arnd Bergmann <arnd@arndb.de>

To make me revisit this code.

Fixes: a9cb97c3 ("media: dvb_frontend: be sure to init dvb_frontend_handle_ioctl() return code")
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

As smatch warned:
	drivers/media/dvb-core/dvb_frontend.c:2468 dvb_frontend_handle_ioctl() error: uninitialized symbol 'err'.

The ioctl handler actually got a regression here: before changeset
d73dcf0c ("media: dvb_frontend: cleanup ioctl handling logic"),
the code used to return -EOPNOTSUPP if an ioctl handler was not
implemented on a driver. After the change, it may return a random
value.

Fixes: d73dcf0c ("media: dvb_frontend: cleanup ioctl handling logic")

Cc: stable@vger.kernel.org
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>
Tested-by: NDaniel Scheller <d.scheller@gmx.net>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

There were some troubles there:
	drivers/media/dvb-core/dvb_frontend.c:379: warning: No description found for parameter 'fe'
	drivers/media/dvb-core/dvb_frontend.c:379: warning: No description found for parameter 'check_wrapped'
	drivers/media/dvb-core/dvb_frontend.c:1265: warning: No description found for parameter 'p_out'
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

dvb_frontend_invoke_release() may free the frontend struct.
So, the free logic can't update it anymore after calling it.

That's OK, as __dvb_frontend_free() is called only when the
krefs are zeroed, so nobody is using it anymore.

That should fix the following KASAN error:

The KASAN report looks like this (running on kernel 3e0cc09a (4.14-rc5+)):
==================================================================
BUG: KASAN: use-after-free in __dvb_frontend_free+0x113/0x120
Write of size 8 at addr ffff880067d45a00 by task kworker/0:1/24

CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.14.0-rc5-43687-g06ab8a23e0e6 #545
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
 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
 kasan_report+0x23d/0x350 mm/kasan/report.c:409
 __asan_report_store8_noabort+0x1c/0x20 mm/kasan/report.c:435
 __dvb_frontend_free+0x113/0x120 drivers/media/dvb-core/dvb_frontend.c:156
 dvb_frontend_put+0x59/0x70 drivers/media/dvb-core/dvb_frontend.c:176
 dvb_frontend_detach+0x120/0x150 drivers/media/dvb-core/dvb_frontend.c:2803
 dvb_usb_adapter_frontend_exit+0xd6/0x160 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:340
 dvb_usb_adapter_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:116
 dvb_usb_exit+0x9b/0x200 drivers/media/usb/dvb-usb/dvb-usb-init.c:132
 dvb_usb_device_exit+0xa5/0xf0 drivers/media/usb/dvb-usb/dvb-usb-init.c:295
 usb_unbind_interface+0x21c/0xa90 drivers/usb/core/driver.c:423
 __device_release_driver drivers/base/dd.c:861
 device_release_driver_internal+0x4f1/0x5c0 drivers/base/dd.c:893
 device_release_driver+0x1e/0x30 drivers/base/dd.c:918
 bus_remove_device+0x2f4/0x4b0 drivers/base/bus.c:565
 device_del+0x5c4/0xab0 drivers/base/core.c:1985
 usb_disable_device+0x1e9/0x680 drivers/usb/core/message.c:1170
 usb_disconnect+0x260/0x7a0 drivers/usb/core/hub.c:2124
 hub_port_connect drivers/usb/core/hub.c:4754
 hub_port_connect_change drivers/usb/core/hub.c:5009
 port_event drivers/usb/core/hub.c:5115
 hub_event+0x1318/0x3740 drivers/usb/core/hub.c:5195
 process_one_work+0xc73/0x1d90 kernel/workqueue.c:2119
 worker_thread+0x221/0x1850 kernel/workqueue.c:2253
 kthread+0x363/0x440 kernel/kthread.c:231
 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431

Allocated by task 24:
 save_stack_trace+0x1b/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
 kmem_cache_alloc_trace+0x11e/0x2d0 mm/slub.c:2772
 kmalloc ./include/linux/slab.h:493
 kzalloc ./include/linux/slab.h:666
 dtt200u_fe_attach+0x4c/0x110 drivers/media/usb/dvb-usb/dtt200u-fe.c:212
 dtt200u_frontend_attach+0x35/0x80 drivers/media/usb/dvb-usb/dtt200u.c:136
 dvb_usb_adapter_frontend_init+0x32b/0x660 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:286
 dvb_usb_adapter_init drivers/media/usb/dvb-usb/dvb-usb-init.c:86
 dvb_usb_init drivers/media/usb/dvb-usb/dvb-usb-init.c:162
 dvb_usb_device_init+0xf73/0x17f0 drivers/media/usb/dvb-usb/dvb-usb-init.c:277
 dtt200u_usb_probe+0xa1/0xe0 drivers/media/usb/dvb-usb/dtt200u.c:155
 usb_probe_interface+0x35d/0x8e0 drivers/usb/core/driver.c:361
 really_probe drivers/base/dd.c:413
 driver_probe_device+0x610/0xa00 drivers/base/dd.c:557
 __device_attach_driver+0x230/0x290 drivers/base/dd.c:653
 bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463
 __device_attach+0x26b/0x3c0 drivers/base/dd.c:710
 device_initial_probe+0x1f/0x30 drivers/base/dd.c:757
 bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523
 device_add+0xd0b/0x1660 drivers/base/core.c:1835
 usb_set_configuration+0x104e/0x1870 drivers/usb/core/message.c:1932
 generic_probe+0x73/0xe0 drivers/usb/core/generic.c:174
 usb_probe_device+0xaf/0xe0 drivers/usb/core/driver.c:266
 really_probe drivers/base/dd.c:413
 driver_probe_device+0x610/0xa00 drivers/base/dd.c:557
 __device_attach_driver+0x230/0x290 drivers/base/dd.c:653
 bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463
 __device_attach+0x26b/0x3c0 drivers/base/dd.c:710
 device_initial_probe+0x1f/0x30 drivers/base/dd.c:757
 bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523
 device_add+0xd0b/0x1660 drivers/base/core.c:1835
 usb_new_device+0x7b8/0x1020 drivers/usb/core/hub.c:2457
 hub_port_connect drivers/usb/core/hub.c:4903
 hub_port_connect_change drivers/usb/core/hub.c:5009
 port_event drivers/usb/core/hub.c:5115
 hub_event+0x194d/0x3740 drivers/usb/core/hub.c:5195
 process_one_work+0xc73/0x1d90 kernel/workqueue.c:2119
 worker_thread+0x221/0x1850 kernel/workqueue.c:2253
 kthread+0x363/0x440 kernel/kthread.c:231
 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431

Freed by task 24:
 save_stack_trace+0x1b/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459
 kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:524
 slab_free_hook mm/slub.c:1390
 slab_free_freelist_hook mm/slub.c:1412
 slab_free mm/slub.c:2988
 kfree+0xf6/0x2f0 mm/slub.c:3919
 dtt200u_fe_release+0x3c/0x50 drivers/media/usb/dvb-usb/dtt200u-fe.c:202
 dvb_frontend_invoke_release.part.13+0x1c/0x30 drivers/media/dvb-core/dvb_frontend.c:2790
 dvb_frontend_invoke_release drivers/media/dvb-core/dvb_frontend.c:2789
 __dvb_frontend_free+0xad/0x120 drivers/media/dvb-core/dvb_frontend.c:153
 dvb_frontend_put+0x59/0x70 drivers/media/dvb-core/dvb_frontend.c:176
 dvb_frontend_detach+0x120/0x150 drivers/media/dvb-core/dvb_frontend.c:2803
 dvb_usb_adapter_frontend_exit+0xd6/0x160 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:340
 dvb_usb_adapter_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:116
 dvb_usb_exit+0x9b/0x200 drivers/media/usb/dvb-usb/dvb-usb-init.c:132
 dvb_usb_device_exit+0xa5/0xf0 drivers/media/usb/dvb-usb/dvb-usb-init.c:295
 usb_unbind_interface+0x21c/0xa90 drivers/usb/core/driver.c:423
 __device_release_driver drivers/base/dd.c:861
 device_release_driver_internal+0x4f1/0x5c0 drivers/base/dd.c:893
 device_release_driver+0x1e/0x30 drivers/base/dd.c:918
 bus_remove_device+0x2f4/0x4b0 drivers/base/bus.c:565
 device_del+0x5c4/0xab0 drivers/base/core.c:1985
 usb_disable_device+0x1e9/0x680 drivers/usb/core/message.c:1170
 usb_disconnect+0x260/0x7a0 drivers/usb/core/hub.c:2124
 hub_port_connect drivers/usb/core/hub.c:4754
 hub_port_connect_change drivers/usb/core/hub.c:5009
 port_event drivers/usb/core/hub.c:5115
 hub_event+0x1318/0x3740 drivers/usb/core/hub.c:5195
 process_one_work+0xc73/0x1d90 kernel/workqueue.c:2119
 worker_thread+0x221/0x1850 kernel/workqueue.c:2253
 kthread+0x363/0x440 kernel/kthread.c:231
 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431

The buggy address belongs to the object at ffff880067d45500
 which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 1280 bytes inside of
 2048-byte region [ffff880067d45500, ffff880067d45d00)
The buggy address belongs to the page:
page:ffffea00019f5000 count:1 mapcount:0 mapping:          (null)
index:0x0 compound_mapcount: 0
flags: 0x100000000008100(slab|head)
raw: 0100000000008100 0000000000000000 0000000000000000 00000001000f000f
raw: dead000000000100 dead000000000200 ffff88006c002d80 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff880067d45900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff880067d45980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff880067d45a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff880067d45a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff880067d45b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Fixes: ead66600 ("media: dvb_frontend: only use kref after initialized")
Reported-by: NAndrey Konovalov <andreyknvl@google.com>
Suggested-by: NMatthias Schwarzott <zzam@gentoo.org>
Tested-by: NAndrey Konovalov <andreyknvl@google.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Follow-up to: ead66600 ("media: dvb_frontend: only use kref after initialized")

The aforementioned commit fixed refcount OOPSes when demod driver attaching
succeeded but tuner driver didn't. However, the use count of the attached
demod drivers don't go back to zero and thus couldn't be cleanly unloaded.
Improve on this by calling dvb_frontend_invoke_release() in
__dvb_frontend_free() regardless of fepriv being NULL, instead of returning
when fepriv is NULL. This is safe to do since _invoke_release() will check
for passed pointers being valid before calling the .release() function.

[mchehab@s-opensource.com: changed the logic a little bit to reduce
 conflicts with another bug fix patch under review]
Fixes: ead66600 ("media: dvb_frontend: only use kref after initialized")
Signed-off-by: NDaniel Scheller <d.scheller@gmx.net>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Fix a bunch of coding style issues found by checkpatch on the
part of the code that the previous patches touched.

WARNING: please, no space before tabs
+ * ^I^Icallback.$

ERROR: space required before the open parenthesis '('
+	switch(cmd) {

WARNING: line over 80 characters
+			err = dtv_property_process_get(fe, &getp, tvp + i, file);

WARNING: line over 80 characters
+			err = fe->ops.diseqc_recv_slave_reply(fe, (struct dvb_diseqc_slave_reply*) parg);

ERROR: "(foo*)" should be "(foo *)"
+			err = fe->ops.diseqc_recv_slave_reply(fe, (struct dvb_diseqc_slave_reply*) parg);

WARNING: line over 80 characters
+				err = fe->ops.read_signal_strength(fe, (__u16 *) parg);
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Simplify the get property handling and move it to the existing
code at dtv_property_process_get() directly.
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Since all properties in the func dtv_property_process_set() use
at most 4 bytes arguments, change the code to pass
u32 cmd and u32 data as function arguments, instead of passing a
pointer to the entire struct dtv_property *tvp.

Instead of having a generic dtv_property_dump(), added its own
properties debug logic in the dtv_property_process_set().
Signed-off-by: NSatendra Singh Thakur <satendra.t@samsung.com>
Reviewed-by: NShuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

There are several problems with regards to the return of
FE_SET_PROPERTY. The original idea were to return per-property
return codes via tvp->result field, and to return an updated
set of values.

However, that never worked. What's actually implemented is:

- the FE_SET_PROPERTY implementation doesn't call .get_frontend
  callback in order to get the actual parameters after return;

- the tvp->result field is only filled if there's no error.
  So, it is always filled with zero;

- FE_SET_PROPERTY doesn't call memdup_user() nor any other
  copy_to_user() function. So, any changes to the properties
  will be lost;

- FE_SET_PROPERTY is declared as a write-only ioctl (IOW).

While we could fix the above, it could cause regressions.

So, let's just assume what the code really does, updating
the documentation accordingly and removing the logic that
would update the discarded tvp->result.
Reviewed-by: NShuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Two readonly ioctls can't be allowed if the frontend device
is opened in read only mode. Explain why.

Reviewed by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

In the past, I guess the idea was to use state in order to
allow an autofush logic. However, in the current code, it is
used only for debug messages, on a poor man's solution, as
there's already a debug message to indicate when the properties
got flushed.

So, just get rid of it for good.
Reviewed-by: NShuah Khan <shuahkg@osg.samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Currently, there are two handlers for ioctls:
 - dvb_frontend_ioctl_properties()
 - dvb_frontend_ioctl_legacy()

Despite their names, both handles non-legacy DVB ioctls.

Besides that, there's no reason why to not handle all ioctls
on a single handler function.

So, merge them into a single function (dvb_frontend_handle_ioctl)
and reorganize the ioctl's to indicate what's the current DVB
API and what's deprecated.

Despite the big diff, the handling logic for each ioctl is the
same as before.
Reviewed-by: NShuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Use a switch() on this function, just like on other ioctl
handlers and handle parameters inside each part of the
switch.

That makes it easier to integrate with the already existing
ioctl handler function.
Reviewed-by: NShuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Now that all clients of set_property() were removed, get rid
of this callback.
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Only lg2160 implement gets_property, but there's no need for that,
as no other driver calls this callback, as get_frontend() does the
same, and set_frontend() also calls lg2160 get_frontend().

So, get rid of it.
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>
Reviewed-by: NMichael Ira Krufky <mkrufky@linuxtv.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

As reported by Laurent, when a DVB frontend need to register
two drivers (e. g. a tuner and a demod), if the second driver
fails to register (for example because it was not compiled),
the error handling logic frees the frontend by calling
dvb_frontend_detach(). That used to work fine, but changeset
1f862a68 ("[media] dvb_frontend: move kref to struct dvb_frontend")
added a kref at struct dvb_frontend. So, now, instead of just
freeing the data, the error handling do a kref_put().

That works fine only after dvb_register_frontend() succeeds.

While it would be possible to add a helper function that
would be initializing earlier the kref, that would require
changing every single DVB frontend on non-trivial ways, and
would make frontends different than other drivers.

So, instead of doing that, let's focus on the real issue:
only call kref_put() after kref_init(). That's easy to
check, as, when the dvb frontend is successfuly registered,
it will allocate its own private struct. So, if such
struct is allocated, it means that it is safe to use
kref_put(). If not, then nobody is using yet the frontend,
and it is safe to just deallocate it.

Fixes: 1f862a68 ("[media] dvb_frontend: move kref to struct dvb_frontend")
Reported-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

struct dtv_cmds_h is just an ancillary struct used by the
dvb_frontend.c to internally store frontend commands.

It doesn't belong to the userspace header, nor it is used anywhere,
except inside the DVB core. So, remove it from the header.
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

GIT_AUTHOR_NAME=Colin King
GIT_AUTHOR_EMAIL=colin.king@canonical.com

In a previous commit, we added FE_NONE as an unknown fe_status.
Initialize variable s to FE_NONE instead of the more opaque value 0.
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Reviewed-by: NShuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

The fe_status variable s is not initialized meaning it can have any
random garbage status.  This could be problematic if fe->ops.tune is
false as s is not updated by the call to fe->ops.tune() and a
subsequent check on the change status will using a garbage value.
Fix this by adding FE_NONE to the enum fe_status and initializing
s to this.

Detected by CoverityScan, CID#112887 ("Uninitialized scalar variable")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Reviewed-by: NShuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>

Fix up affected files that include this signal functionality via sched.h.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Drivers might try to access and run enable_source and disable_source
handlers when the driver that implements these handlers is clearing
the handlers during its unregister.

Fix the following race condition:

process 1				process 2

request video streaming			unbind au0828
v4l2 checks if tuner is free
...					...

					au0828_unregister_media_device()
...					...
					(doesn't hold graph_mutex)
					mdev->enable_source = NULL;
if (mdev && mdev->enable_source)	mdev->disable_source = NULL;
	mdev->enable_source()
(enable_source holds graph_mutex)

As shown above enable_source check is done without holding the graph_mutex.
If unbind happens to be in progress, au0828 could clear enable_source and
disable_source handlers leading to null pointer de-reference.

Fix it by protecting enable_source and disable_source set and clear and
protecting enable_source and disable_source handler access and the call
itself.

process 1				process 2

request video streaming			unbind au0828
v4l2 checks if tuner is free
...					...

					au0828_unregister_media_device()
...					...
					(hold graph_mutex while clearing)
					mdev->enable_source = NULL;
if (mdev)				mdev->disable_source = NULL;
(hold graph_mutex to check and
 call enable_source)
    if (mdev->enable_source)
	mdev->enable_source()

If graph_mutex is held to just heck for handler being null and needs to be
released before calling the handler, there will be another window for the
handlers to be cleared. Hence, enable_source and disable_source handlers
no longer hold the graph_mutex and expect callers to hold it to avoid
forcing them release the graph_mutex before calling the handlers.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Drop the FSF's postal address from the source code files that typically
contain mostly the license text. Of the 628 removed instances, 578 are
outdated.

The patch has been created with the following command without manual edits:

git grep -l "675 Mass Ave\|59 Temple Place\|51 Franklin St" -- \
	drivers/media/ include/media|while read i; do i=$i perl -e '
open(F,"< $ENV{i}");
$a=join("", <F>);
$a =~ s/[ \t]*\*\n.*You should.*\n.*along with.*\n.*(\n.*USA.*$)?\n//m
	&& $a =~ s/(^.*)Or, (point your browser to) /$1To obtain the license, $2\n$1/m;
close(F);
open(F, "> $ENV{i}");
print F $a;
close(F);'; done
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>

While this patch sounded a good idea, unfortunately, it causes
bad dependencies, as drivers that would otherwise work without
the DVB core will now break:

ERROR: "dvb_tuner_simple_release" [drivers/media/tuners/tea5767.ko] undefined!
ERROR: "dvb_tuner_simple_release" [drivers/media/tuners/tea5761.ko] undefined!
ERROR: "dvb_tuner_simple_release" [drivers/media/tuners/tda827x.ko] undefined!
ERROR: "dvb_tuner_simple_release" [drivers/media/tuners/tda18218.ko] undefined!
ERROR: "dvb_tuner_simple_release" [drivers/media/tuners/qt1010.ko] undefined!
ERROR: "dvb_tuner_simple_release" [drivers/media/tuners/mt2266.ko] undefined!
ERROR: "dvb_tuner_simple_release" [drivers/media/tuners/mt20xx.ko] undefined!
ERROR: "dvb_tuner_simple_release" [drivers/media/tuners/mt2060.ko] undefined!
ERROR: "dvb_tuner_simple_release" [drivers/media/tuners/mc44s803.ko] undefined!
ERROR: "dvb_tuner_simple_release" [drivers/media/tuners/fc0013.ko] undefined!
ERROR: "dvb_tuner_simple_release" [drivers/media/tuners/fc0012.ko] undefined!
ERROR: "dvb_tuner_simple_release" [drivers/media/tuners/fc0011.ko] undefined!

So, we have to revert it.

Note: as the argument for the release ops changed from "int"
to "void", we needed to change it at the revert patch, to
avoid compilation issues like:
	drivers/media/tuners/tea5767.c:437:23: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types]
	  .release           = tea5767_release,
	                       ^~~~~~~~~~~~~~~

This reverts commit 22a613e8.
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

This commit amends my old commit fe35637b ("[media] dvb_frontend:
eliminate blocking wait in dvb_unregister_frontend()"), which added
kref to struct dvb_frontend_private.  It turned out that there are
several use-after-free bugs left, which affect the struct
dvb_frontend.  Protecting it with kref also protects struct
dvb_frontend_private, so we can simply move it.

This is how the use-after-free looks like in KASAN:

    BUG: KASAN: use-after-free in string+0x60/0xb1 at addr ffff880033bd9fc0
    Read of size 1 by task kworker/0:2/617
    CPU: 0 PID: 617 Comm: kworker/0:2 Not tainted 4.8.0-rc1-hosting+ #60
    Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
    Workqueue: usb_hub_wq hub_event
     0000000000000000 ffff880033757218 ffffffff81394e50 ffff880033bd9fd0
     ffff880035c03b00 ffff880033757240 ffffffff811f271d ffff880033bd9fc0
     1ffff1000677b3f8 ffffed000677b3f8 ffff8800337572b8 ffffffff811f2afe
    Call Trace:
     [...]
     [<ffffffff813a2d2f>] vsnprintf+0x39d/0x7e9
     [<ffffffff813993f9>] add_uevent_var+0x10f/0x1dc
     [<ffffffff814fe5ca>] rc_dev_uevent+0x55/0x6f
     [<ffffffff814438f8>] dev_uevent+0x2e1/0x316
     [<ffffffff81399744>] kobject_uevent_env+0x27e/0x701
     [<ffffffff81399bd2>] kobject_uevent+0xb/0xd
     [<ffffffff81443445>] device_del+0x322/0x383
     [<ffffffff81500c0c>] rc_unregister_device+0x98/0xc3
     [<ffffffff81508fb4>] dvb_usb_remote_exit+0x7a/0x90
     [<ffffffff81506157>] dvb_usb_exit+0x1d/0xe5
     [<ffffffff81506e90>] dvb_usb_device_exit+0x69/0x7d
     [<ffffffff8150a181>] pctv452e_usb_disconnect+0x7b/0x80
     [...]
    Object at ffff880033bd9fc0, in cache kmalloc-16 size: 16
    Allocated:
     [...]
    Freed:
    PID = 617
     [...]
     [<ffffffff811f034c>] kfree+0xd9/0x166
     [<ffffffff814fe513>] ir_free_table+0x2f/0x51
     [<ffffffff81500bc1>] rc_unregister_device+0x4d/0xc3
     [<ffffffff81508fb4>] dvb_usb_remote_exit+0x7a/0x90
     [<ffffffff81506157>] dvb_usb_exit+0x1d/0xe5
     [<ffffffff81506e90>] dvb_usb_device_exit+0x69/0x7d
     [<ffffffff8150a181>] pctv452e_usb_disconnect+0x7b/0x80

Another one:

    BUG: KASAN: use-after-free in do_sys_poll+0x336/0x6b8 at addr ffff88003563fcc0
    Read of size 8 by task tuner on fronte/1042
    CPU: 1 PID: 1042 Comm: tuner on fronte Tainted: G    B           4.8.0-rc1-hosting+ #60
    Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
     0000000000000000 ffff88003353f910 ffffffff81394e50 ffff88003563fd80
     ffff880035c03200 ffff88003353f938 ffffffff811f271d ffff88003563fc80
     1ffff10006ac7f98 ffffed0006ac7f98 ffff88003353f9b0 ffffffff811f2afe
    Call Trace:
     [...]
     [<ffffffff812289b3>] do_sys_poll+0x336/0x6b8
     [...]
     [<ffffffff81228ed9>] SyS_poll+0xa9/0x194
     [...]
    Object at ffff88003563fc80, in cache kmalloc-256 size: 256
    Allocated:
     [...]
    Freed:
    PID = 617
     [...]
     [<ffffffff811f034c>] kfree+0xd9/0x166
     [<ffffffff814eb60d>] dvb_unregister_device+0xd6/0xe5
     [<ffffffff814fa4ed>] dvb_unregister_frontend+0x4b/0x66
     [<ffffffff8150810b>] dvb_usb_adapter_frontend_exit+0x69/0xac
     [<ffffffff8150617d>] dvb_usb_exit+0x43/0xe5
     [<ffffffff81506e90>] dvb_usb_device_exit+0x69/0x7d
     [<ffffffff8150a181>] pctv452e_usb_disconnect+0x7b/0x80
Signed-off-by: NMax Kellermann <max.kellermann@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Prepare for making "release" asynchronous (via kref).  Some operations
may need to be run synchronously in dvb_frontend_detach(), and that's
why we need a "detach" callback.
Signed-off-by: NMax Kellermann <max.kellermann@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

This code duplication is confusing and error prone.  Let's merge them
by moving the release/dvb_detach call into one function with one
Signed-off-by: NMax Kellermann <max.kellermann@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

It is not clear what this return value means.  All implemenations
return 0, and the one caller ignores the value.  Let's remove this
useless return value completely.
Signed-off-by: NMax Kellermann <max.kellermann@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Most release callback functions are identical: free the "tuner_priv"
and clear it.  Let's eliminate some bloat by providing this simple
implementation in the dvb_frontend library.
Signed-off-by: NMax Kellermann <max.kellermann@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>