media: dvb-core: Fix use-after-free due on race condition at dvb_net

A race condition may occur between the .disconnect function, which
is called when the device is disconnected, and the dvb_device_open()
function, which is called when the device node is open()ed.
This results in several types of UAFs.

The root cause of this is that you use the dvb_device_open() function,
which does not implement a conditional statement
that checks 'dvbnet->exit'.

So, add 'remove_mutex` to protect 'dvbnet->exit' and use
locked_dvb_net_open() function to check 'dvbnet->exit'.

[mchehab: fix a checkpatch warning]

Link: https://lore.kernel.org/linux-media/20221117045925.14297-3-imv4bel@gmail.com
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

media: use eth_hw_addr_set()

Commit 406f42fa0d3c ("net-next: When a bond have a massive amount
of VLANs...") introduced a rbtree for faster Ethernet address look
up. To maintain netdev->dev_addr in this tree we need to make all
the writes to it go through appropriate helpers.

Convert media from memcpy(... 6) and memcpy(... addr_len) to
eth_hw_addr_set():

@@
expression dev, np;
@@
- memcpy(dev->dev_addr, np, 6)
+ eth_hw_addr_set(dev, np)
@@
- memcpy(dev->dev_addr, np, dev->addr_len)
+ eth_hw_addr_set(dev, np)

Make sure we don't cast off const qualifier from dev->dev_addr.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

media: dvb_net: avoid speculation from net slot

The risk of especulation is actually almost-non-existing here,
as there are very few users of TCP/IP using the DVB stack,
as, this is mainly used with DVB-S/S2 cards, and only by people
that receives TCP/IP from satellite connections, which limits
a lot the number of users of such feature(*).

(*) In thesis, DVB-C cards could also benefit from it, but I'm
yet to see a hardware that supports it.

Yet, fixing it is trivial.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

treewide: 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/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 113

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details to
obtain the license point your browser to http www gnu org copyleft
gpl html

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 26 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190523091650.572604764@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

media: dvb_net: fix dvb_net_tx()'s return type

The method ndo_start_xmit() is defined as returning an 'netdev_tx_t',
which is a typedef for an enum type, but the implementation in this
driver returns an 'int'.

Fix this by returning 'netdev_tx_t' in this driver too.

Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

media: dvb: update buffer mmaped flags and frame counter

Now that we have support for a buffer counter and for
error flags, update them at DMX_DQBUF.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

media: move dvb kAPI headers to include/media

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

Move the headers to it.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

media: dvb_net: let dynamic debug enable some DVB net handling

pr_debug() and netdev_dbg() can be enabled/disabled dynamically
via sysfs. So, stop hidding them under ULE_DEBUG config macro.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

media: dvb-core: allow users to enable DVB net ULE debug

This debug option is there for a long time, but it is only
enabled by editing the source code. Due to that, a breakage
inside its code was only noticed years after a change at
the ULE handling logic.

Make it a Kconfig parameter, as it makes easier for
advanced users to enable, and allow test if the compilation
won't be broken in the future.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

media: dvb_net: ensure that dvb_net_ule_handle is fully initialized

commit efb9ab67255f ("[media] dvb_net: prepare to split a very
complex function") changed the ULE handling logic, simplifying it.
However, it forgot to keep the initialization for .priv and to
zero .ule_hist fields.

The lack of .priv cause crashes if dvb_net_ule() is called, as
the function assuems that .priv field to be initialized.

With regards to .ule_hist, the current logic is broken and don't
even compile if ULE_DEBUG. Fix it by making the debug vars static
again, and be sure to pass iov parameter to dvb_net_ule_check_crc().

Fixes: efb9ab67255f ("[media] dvb_net: prepare to split a very complex function")

Suggested-by: Ron Economos <w6rz@comcast.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

media: dvb_net: stop abusing /** for comments

The comments that start with "/**" aren't kernel-doc stuff.
So, just start them with "/*".

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

networking: make skb_put & friends return void pointers

It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:

@@
expression SKB, LEN;
typedef u8;
identifier fn = { skb_put, __skb_put };
@@
- *(fn(SKB, LEN))
+ *(u8 *)fn(SKB, LEN)

@@
expression E, SKB, LEN;
identifier fn = { skb_put, __skb_put };
type T;
@@
- E = ((T *)(fn(SKB, LEN)))
+ E = fn(SKB, LEN)

which actually doesn't cover pskb_put since there are only three
users overall.

A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

networking: introduce and use skb_put_data()

A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.

An spatch similar to the one for skb_put_zero() converts many
of the places using it:

@@
identifier p, p2;
expression len, skb, data;
type t, t2;
@@
(
-p = skb_put(skb, len);
+p = skb_put_data(skb, data, len);
|
-p = (t)skb_put(skb, len);
+p = skb_put_data(skb, data, len);
)
(
p2 = (t2)p;
-memcpy(p2, data, len);
|
-memcpy(p, data, len);
)

@@
type t, t2;
identifier p, p2;
expression skb, data;
@@
t *p;
...
(
-p = skb_put(skb, sizeof(t));
+p = skb_put_data(skb, data, sizeof(t));
|
-p = (t *)skb_put(skb, sizeof(t));
+p = skb_put_data(skb, data, sizeof(t));
)
(
p2 = (t2)p;
-memcpy(p2, data, sizeof(*p));
|
-memcpy(p, data, sizeof(*p));
)

@@
expression skb, len, data;
@@
-memcpy(skb_put(skb, len), data, len);
+skb_put_data(skb, data, len);

(again, manually post-processed to retain some comments)

Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[media] media: Drop FSF's postal address from the source code files

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: Sakari Ailus <sakari.ailus@linux.intel.com>

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

This was entirely automated, using the script by Al:

PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[media] dvb: avoid warning in dvb_net

With gcc-5 or higher on x86, we can get a bogus warning in the
dvb-net code:

drivers/media/dvb-core/dvb_net.c: In function 'dvb_net_ule':
arch/x86/include/asm/string_32.h:78:22: error: '*((void *)&dest_addr+4)' may be used uninitialized in this function [-Werror=maybe-uninitialized]

The problem here is that gcc doesn't track all of the conditions
to prove it can't end up copying uninitialized data.
This changes the logic around so we zero out the destination
address earlier when we determine that it is not set here.
This allows the compiler to figure it out.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

[media] dvb-net: split the logic at dvb_net_ule() into other functions

This function is too big and too complex, making really hard
to understand what's there.

Split it into sub-routines, in order to make it easier to be
understood, and to allow gcc to better parse it.

As a bonus, it gets rid of a goto in the middle of a routine.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

[media] dvb_net: prepare to split a very complex function

The dvb_net code has a really complex function, meant to handle
DVB network packages: it is long, has several loops and ifs
inside, and even cause warnings with gcc5.

Prepare it to be split into smaller functions by storing all
arguments and internal vars inside a struct.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

[media] dvb-core: get rid of demux optional circular buffer

There is a provision at the dvb_demux.c to use a vmalloc'ed
circular buffer, enabled via an extra #ifdef option that it
is not at Kconfig. Enabling it will only make the Kernel to
allocate/deallocate such buffer, but no code would actually
use it. So, no practical effect, except for sparing some
memory without any good reason.

So, get rid of such dead code.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

[media] dvb-core: use pr_foo() instead of printk()

The dvb-core directly calls printk() without using the modern
printk macros, or using the proper printk levels. Change it
to use pr_foo().

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

net: deprecate eth_change_mtu, remove usage

With centralized MTU checking, there's nothing productive done by
eth_change_mtu that isn't already done in dev_set_mtu, so mark it as
deprecated and remove all usage of it in the kernel. All callers have been
audited for calls to alloc_etherdev* or ether_setup directly, which means
they all have a valid dev->min_mtu and dev->max_mtu. Now eth_change_mtu
prints out a netdev_warn about being deprecated, for the benefit of
out-of-tree drivers that might be utilizing it.

Of note, dvb_net.c actually had dev->mtu = 4096, while using
eth_change_mtu, meaning that if you ever tried changing it's mtu, you
couldn't set it above 1500 anymore. It's now getting dev->max_mtu also set
to 4096 to remedy that.

v2: fix up lantiq_etop, missed breakage due to drive not compiling on x86

CC: netdev@vger.kernel.org
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[media] dvb: use ktime_t for internal timeout

The dvb demuxer code uses a 'struct timespec' to pass a timeout
as absolute time. This will cause problems on 32-bit architectures
in 2038 when time_t overflows, and it is racy with a concurrent
settimeofday() call.

This patch changes the code to use ktime_get() instead, using
the monotonic time base to avoid both the race and the overflow.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

[media] dvb: modify core to implement interfaces/entities at MC new gen

The Media Controller New Generation redefines the types for both
interfaces and entities to be used on DVB. Make the needed
changes at the DVB core for all interfaces, entities and
data and interface links to appear in the graph.

Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] dvb: get rid of enum dmx_success

This enum is not actually used anymore. The only value used from
the enum is DMX_OK, passed as a parameter on two callbacks.

Yet, this value is not used anywhere. So, just remove it.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] dvb_core: Replace memset with eth_zero_addr

Use eth_zero_addr to assign the zero address to the given address
array instead of memset when second argument is address of zero.

The Coccinelle semantic patch that makes this change is as follows:

// <smpl>
@eth_zero_addr@
expression e;
@@

-memset(e,0x00,ETH_ALEN);
+eth_zero_addr(e);
// </smpl>

Signed-off-by: Vaishali Thakkar <vthakkar1994@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

net: Kill dev_rebuild_header

Now that there are no more users kill dev_rebuild_header and all of it's
implementations.

This is long overdue.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[media] dvb core: rename the media controller entities

Prefix all DVB media controller entities with "dvb-" and use dash
instead of underline at the names.

Requested-by: Hans Verkuil <hans.verkuil@cisco.com>

Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] dvb_net: add support for DVB net node at the media controller

Make the dvb core network support aware of the media controller and
register the corresponding devices.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] dvb_net: Convert local hex dump to print_hex_dump_debug

Use the generic facility instead of a home-grown one.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] dvb_net: Use standard debugging facilities

Convert dprintk to netdev_dbg where appropriate.
Remove dvb_net_debug module_param.
Remove __func__ from output as that can be added by dynamic_debug.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] dvb_net: Use vsprintf %pM extension to print Ethernet addresses

No need for more macros, so remove them and use the kernel extension.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] media: dvb_core: replace a magic number by a macro

It's better to use TS_SC instead of magic number 0xC0.

[m.chehab@samsung.com: patch rebased and message rewritten, as this
patch conflicted with an already applied patch]

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] dvb-net: Fix probable mask then right shift defects

Precedence of & and >> is not the same and is not left to right.
shift has higher precedence and should be done after the mask.

Add parentheses around the mask.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

net: set name_assign_type in alloc_netdev()

Extend alloc_netdev{,_mq{,s}}() to take name_assign_type as argument, and convert
all users to pass NET_NAME_UNKNOWN.

Coccinelle patch:

@@
expression sizeof_priv, name, setup, txqs, rxqs, count;
@@

(
-alloc_netdev_mqs(sizeof_priv, name, setup, txqs, rxqs)
+alloc_netdev_mqs(sizeof_priv, name, NET_NAME_UNKNOWN, setup, txqs, rxqs)
|
-alloc_netdev_mq(sizeof_priv, name, setup, count)
+alloc_netdev_mq(sizeof_priv, name, NET_NAME_UNKNOWN, setup, count)
|
-alloc_netdev(sizeof_priv, name, setup)
+alloc_netdev(sizeof_priv, name, NET_NAME_UNKNOWN, setup)
)

v9: move comments here from the wrong commit

Signed-off-by: Tom Gundersen <teg@jklm.no>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

media: dvb_core: slight optimization of addr compare

Use possibly more efficient ether_addr_equal
instead of memcmp.

Cc: Mauro Carvalho Chehab <m.chehab@samsung.com>
Cc: linux-media@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

dvb_net: don't mess with ->f_op in ->release()

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

[media] demux.h: Remove duplicated enum

"enum dmx_ts_pes" and "typedef enum dmx_pes_type_t" are just the
same enum declared twice, since Kernel (2.6.12). There's no reason
to duplicate it there, and sparse complains about that:
drivers/media/dvb-core/dmxdev.c:600:55: warning: mixing different enum types
So, remove the internal define, keeping just the external one.
Internally, use only "enum dmx_ts_pes", as it is too late to drop
dmx_pes_type_t from the userspace API.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

net: add ETH_P_802_3_MIN

Add a new constant ETH_P_802_3_MIN, the minimum ethernet type for
an 802.3 frame. Frames with a lower value in the ethernet type field
are Ethernet II.

Also update all the users of this value that David Miller and
I could find to use the new constant.

Also correct a bug in util.c. The comparison with ETH_P_802_3_MIN
should be >= not >.

As suggested by Jesse Gross.

Compile tested only.

Cc: David Miller <davem@davemloft.net>
Cc: Jesse Gross <jesse@nicira.com>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: John W. Linville <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Bart De Schuymer <bart.de.schuymer@pandora.be>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: linux-bluetooth@vger.kernel.org
Cc: netfilter-devel@vger.kernel.org
Cc: bridge@lists.linux-foundation.org
Cc: linux-wireless@vger.kernel.org
Cc: linux1394-devel@lists.sourceforge.net
Cc: linux-media@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: dev@openvswitch.org
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

[media] dvb: push down ioctl lock in dvb_usercopy

Since most dvb ioctls wrap their real work with dvb_usercopy, the static mutex
used in dvb_usercopy effectively is a global lock for dvb ioctls.
Unfortunately, frontend ioctls can be blocked by the frontend thread for
several seconds; this leads to unacceptable lock contention. Mitigate that by
pushing the mutex from dvb_usercopy down to the individual, device specific
ioctls.
There are 10 such ioctl functions using dvb_usercopy, either calling it
directly, or via the trivial wrapper dvb_generic_ioctl. The following already
employ their own locking and look safe:
• dvb_demux_ioctl (as per dvb_demux_do_ioctl)
• dvb_dvr_ioctl (as per dvb_dvr_do_ioctl)
• dvb_osd_ioctl (as per single non-trivial callee)
• fdtv_ca_ioctl (as per callees)
• dvb_frontend_ioctl
The following functions do not, and are thus changed to use a device specific
mutex:
• dvb_net_ioctl (as per dvb_net_do_ioctl)
• dvb_ca_en50221_io_ioctl (as per dvb_ca_en50221_io_do_ioctl)
• dvb_video_ioctl
• dvb_audio_ioctl
• dvb_ca_ioctl

Signed-off-by: Nikolaus Schulz <schulz@macnetix.de>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

[media] dvb: move the dvb core one level up

just like the V4L2 core, move the DVB core to drivers/media, as the
intention is to get rid of both "video" and "dvb" directories.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>