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>
Network devices can allocate reasources and private memory using
netdev_ops->ndo_init(). However, the release of these resources
can occur in one of two different places.
Either netdev_ops->ndo_uninit() or netdev->destructor().
The decision of which operation frees the resources depends upon
whether it is necessary for all netdev refs to be released before it
is safe to perform the freeing.
netdev_ops->ndo_uninit() presumably can occur right after the
NETDEV_UNREGISTER notifier completes and the unicast and multicast
address lists are flushed.
netdev->destructor(), on the other hand, does not run until the
netdev references all go away.
Further complicating the situation is that netdev->destructor()
almost universally does also a free_netdev().
This creates a problem for the logic in register_netdevice().
Because all callers of register_netdevice() manage the freeing
of the netdev, and invoke free_netdev(dev) if register_netdevice()
fails.
If netdev_ops->ndo_init() succeeds, but something else fails inside
of register_netdevice(), it does call ndo_ops->ndo_uninit(). But
it is not able to invoke netdev->destructor().
This is because netdev->destructor() will do a free_netdev() and
then the caller of register_netdevice() will do the same.
However, this means that the resources that would normally be released
by netdev->destructor() will not be.
Over the years drivers have added local hacks to deal with this, by
invoking their destructor parts by hand when register_netdevice()
fails.
Many drivers do not try to deal with this, and instead we have leaks.
Let's close this hole by formalizing the distinction between what
private things need to be freed up by netdev->destructor() and whether
the driver needs unregister_netdevice() to perform the free_netdev().
netdev->priv_destructor() performs all actions to free up the private
resources that used to be freed by netdev->destructor(), except for
free_netdev().
netdev->needs_free_netdev is a boolean that indicates whether
free_netdev() should be done at the end of unregister_netdevice().
Now, register_netdevice() can sanely release all resources after
ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit()
and netdev->priv_destructor().
And at the end of unregister_netdevice(), we invoke
netdev->priv_destructor() and optionally call free_netdev().
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes the kernel oops when release net_device reference in
advance. In function raw_sendmsg(i think the dgram_sendmsg has the same
problem), there is a race condition between dev_put and dev_queue_xmit
when the device is gong that maybe lead to dev_queue_ximt to see
an illegal net_device pointer.
My test kernel is 3.13.0-32 and because i am not have a real 802154
device, so i change lowpan_newlink function to this:
/* find and hold real wpan device */
real_dev = dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
if (!real_dev)
return -ENODEV;
// if (real_dev->type != ARPHRD_IEEE802154) {
// dev_put(real_dev);
// return -EINVAL;
// }
lowpan_dev_info(dev)->real_dev = real_dev;
lowpan_dev_info(dev)->fragment_tag = 0;
mutex_init(&lowpan_dev_info(dev)->dev_list_mtx);
Also, in order to simulate preempt, i change the raw_sendmsg function
to this:
skb->dev = dev;
skb->sk = sk;
skb->protocol = htons(ETH_P_IEEE802154);
dev_put(dev);
//simulate preempt
schedule_timeout_uninterruptible(30 * HZ);
err = dev_queue_xmit(skb);
if (err > 0)
err = net_xmit_errno(err);
and this is my userspace test code named test_send_data:
int main(int argc, char **argv)
{
char buf[127];
int sockfd;
sockfd = socket(AF_IEEE802154, SOCK_RAW, 0);
if (sockfd < 0) {
printf("create sockfd error: %s\n", strerror(errno));
return -1;
}
send(sockfd, buf, sizeof(buf), 0);
return 0;
}
This is my test case:
root@zhanglin-x-computer:~/develop/802154# uname -a
Linux zhanglin-x-computer 3.13.0-32-generic #57-Ubuntu SMP Tue Jul 15
03:51:08 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
root@zhanglin-x-computer:~/develop/802154# ip link add link eth0 name
lowpan0 type lowpan
root@zhanglin-x-computer:~/develop/802154#
//keep the lowpan0 device down
root@zhanglin-x-computer:~/develop/802154# ./test_send_data &
//wait a while
root@zhanglin-x-computer:~/develop/802154# ip link del link dev lowpan0
//the device is gone
//oops
[381.303307] general protection fault: 0000 [#1]SMP
[381.303407] Modules linked in: af_802154 6lowpan bnep rfcomm
bluetooth nls_iso8859_1 snd_hda_codec_hdmi snd_hda_codec_realtek
rts5139(C) snd_hda_intel
snd_had_codec snd_hwdep snd_pcm snd_page_alloc snd_seq_midi
snd_seq_midi_event snd_rawmidi snd_req intel_rapl snd_seq_device
coretemp i915 kvm_intel
kvm snd_timer snd crct10dif_pclmul crc32_pclmul ghash_clmulni_intel
cypted drm_kms_helper drm i2c_algo_bit soundcore video mac_hid
parport_pc ppdev ip parport hid_generic
usbhid hid ahci r8169 mii libahdi
[381.304286] CPU:1 PID: 2524 Commm: 1 Tainted: G C 0 3.13.0-32-generic
[381.304409] Hardware name: Haier Haier DT Computer/Haier DT Codputer,
BIOS FIBT19H02_X64 06/09/2014
[381.304546] tasks: ffff000096965fc0 ti: ffffB0013779c000 task.ti:
ffffB8013779c000
[381.304659] RIP: 0010:[<ffffffff01621fe1>] [<ffffffff81621fe1>]
__dev_queue_ximt+0x61/0x500
[381.304798] RSP: 0018:ffffB8013779dca0 EFLAGS: 00010202
[381.304880] RAX: 272b031d57565351 RBX: 0000000000000000 RCX: ffff8800968f1a00
[381.304987] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8800968f1a00
[381.305095] RBP: ffff8e013773dce0 R08: 0000000000000266 R09: 0000000000000004
[381.305202] R10: 0000000000000004 R11: 0000000000000005 R12: ffff88013902e000
[381.305310] R13: 000000000000007f R14: 000000000000007f R15: ffff8800968f1a00
[381.305418] FS: 00007fc57f50f740(0000) GS: ffff88013fc80000(0000)
knlGS: 0000000000000000
[381.305540] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[381.305627] CR2: 00007fad0841c000 CR3: 00000001368dd000 CR4: 00000000001007e0
[361.905734] Stack:
[381.305768] 00000000002052d0 000000003facb30a ffff88013779dcc0
ffff880137764000
[381.305898] ffff88013779de70 000000000000007f 000000000000007f
ffff88013902e000
[381.306026] ffff88013779dcf0 ffffffff81622490 ffff88013779dd39
ffffffffa03af9f1
[381.306155] Call Trace:
[381.306202] [<ffffffff81622490>] dev_queue_xmit+0x10/0x20
[381.306294] [<ffffffffa03af9f1>] raw_sendmsg+0x1b1/0x270 [af_802154]
[381.306396] [<ffffffffa03af054>] ieee802154_sock_sendmsg+0x14/0x20 [af_802154]
[381.306512] [<ffffffff816079eb>] sock_sendmsg+0x8b/0xc0
[381.306600] [<ffffffff811d52a5>] ? __d_alloc+0x25/0x180
[381.306687] [<ffffffff811a1f56>] ? kmem_cache_alloc_trace+0x1c6/0x1f0
[381.306791] [<ffffffff81607b91>] SYSC_sendto+0x121/0x1c0
[381.306878] [<ffffffff8109ddf4>] ? vtime_account_user+x54/0x60
[381.306975] [<ffffffff81020d45>] ? syscall_trace_enter+0x145/0x250
[381.307073] [<ffffffff816086ae>] SyS_sendto+0xe/0x10
[381.307156] [<ffffffff8172c87f>] tracesys+0xe1/0xe6
[381.307233] Code: c6 a1 a4 ff 41 8b 57 78 49 8b 47 20 85 d2 48 8b 80
78 07 00 00 75 21 49 8b 57 18 48 85 d2 74 18 48 85 c0 74 13 8b 92 ac
01 00 00 <3b> 50 10 73 08 8b 44 90 14 41 89 47 78 41 f6 84 24 d5 00 00
00
[381.307801] RIP [<ffffffff81621fe1>] _dev_queue_xmit+0x61/0x500
[381.307901] RSP <ffff88013779dca0>
[381.347512] Kernel panic - not syncing: Fatal exception in interrupt
[381.347747] drm_kms_helper: panic occurred, switching back to text console
In my opinion, there is always exist a chance that the device is gong
before call dev_queue_xmit.
I think the latest kernel is have the same problem and that
dev_put should be behind of the dev_queue_xmit.
Signed-off-by: Lin Zhang <xiaolou4617@gmail.com>
Acked-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__bitwise__ used to mean "yes, please enable sparse checks
unconditionally", but now that we dropped __CHECK_ENDIAN__
__bitwise is exactly the same.
There aren't many users, replace it by __bitwise everywhere.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Stefan Schmidt <stefan@osg.samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Akced-by: Lee Duncan <lduncan@suse.com>
I've observed a NULL pointer dereference in ieee802154_del_iface() during
netlink fuzzing. It's the ->wpan_phy dereference here:
phy = dev->ieee802154_ptr->wpan_phy;
My bet is that we're not checking that this is an IEEE802154 interface,
so let's do what ieee802154_nl_get_dev() is doing. (Maybe we should even
be calling this directly?)
Cc: Lennert Buytenhek <buytenh@wantstofly.org>
Cc: Alexander Aring <alex.aring@gmail.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Sergey Lapin <slapin@ossfans.org>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Acked-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: Stefan Schmidt <stefan@osg.samsung.com>
Now genl_register_family() is the only thing (other than the
users themselves, perhaps, but I didn't find any doing that)
writing to the family struct.
In all families that I found, genl_register_family() is only
called from __init functions (some indirectly, in which case
I've add __init annotations to clarifly things), so all can
actually be marked __ro_after_init.
This protects the data structure from accidental corruption.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of providing macros/inline functions to initialize
the families, make all users initialize them statically and
get rid of the macros.
This reduces the kernel code size by about 1.6k on x86-64
(with allyesconfig).
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Static family IDs have never really been used, the only
use case was the workaround I introduced for those users
that assumed their family ID was also their multicast
group ID.
Additionally, because static family IDs would never be
reserved by the generic netlink code, using a relatively
low ID would only work for built-in families that can be
registered immediately after generic netlink is started,
which is basically only the control family (apart from
the workaround code, which I also had to add code for so
it would reserve those IDs)
Thus, anything other than GENL_ID_GENERATE is flawed and
luckily not used except in the cases I mentioned. Move
those workarounds into a few lines of code, and then get
rid of GENL_ID_GENERATE entirely, making it more robust.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This helper function allows family implementations to access
their family's attrbuf. This gets rid of the attrbuf usage
in families, and also adds locking validation, since it's not
valid to use the attrbuf with parallel_ops or outside of the
dumpit callback.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The RIOT-OS stack does send intra-pan frames but don't set the intra pan
flag inside the mac header. It seems this is valid frame addressing but
inefficient. Anyway this patch adds a new function for intra pan
addressing, doesn't matter if intra pan flag or source and destination
are the same. The newly introduction function will be used to check on
intra pan addressing for 6lowpan.
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch reverts commit f9d1ce8f81 ("ieee802154: fix netns settings").
The lowpan interface need to be created inside the net namespace where
the wpan interface is available. The wpan namespace can be changed only
by nl802154 before. Without this patch it's not possible to create a
lowpan interface for a wpan interface which isn't inside init_net
namespace.
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds netns support for 802.15.4 subsystem. Most parts are
copy&pasted from wireless subsystem, it has the identically userspace
API.
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
As the following patch will allow upper devices to follow the call down
lower devices, we need to add dev here and not rely on n->dev.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds necessary handling for use the short address for
802.15.4 6lowpan. It contains support for IPHC address compression
and new matching algorithmn to decide which link layer address will be
used for 802.15.4 frame.
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch will introduce a 6lowpan neighbour private data. Like the
interface private data we handle private data for generic 6lowpan and
for link-layer specific 6lowpan.
The current first use case if to save the short address for a 802.15.4
6lowpan neighbour.
Cc: David S. Miller <davem@davemloft.net>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is time to add netdev_lockdep_set_classes() helper
so that lockdep annotations per device type are easier to manage.
This removes a lot of copies and missing annotations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of using a single bit (__QDISC___STATE_RUNNING)
in sch->__state, use a seqcount.
This adds lockdep support, but more importantly it will allow us
to sample qdisc/class statistics without having to grab qdisc root lock.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>