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commit 4b793acdca0050739b99ace6a8b9e7f717f57c6b upstream.
When HSR interface is sending a frame, it finds a node with
the destination ethernet address from the list.
If there is no node, it calls WARN_ONCE().
But, using WARN_ONCE() for this situation is a little bit overdoing.
So, in this patch, the netdev_err() is used instead.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: George Kennedy <george.kennedy@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 414e7d76af6d3ec2dd4e9079927dbe0e2e4ca914 upstream.
skb_put_padto() will free the sk_buff passed as reference in case of
errors, but we still need to check its return value and decide what to
do.
Detected by CoverityScan, CID#1416688 ("CHECKED_RETURN")
Fixes: ee1c27977284 ("net/hsr: Added support for HSR v1")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4faab8c446def7667adf1f722456c2f4c304069c ]
In the current hsr code, only 0 and 1 protocol versions are valid.
But current hsr code doesn't check the version, which is received by
userspace.
Test commands:
ip link add dummy0 type dummy
ip link add dummy1 type dummy
ip link add hsr0 type hsr slave1 dummy0 slave2 dummy1 version 4
In the test commands, version 4 is invalid.
So, the command should be failed.
After this patch, following error will occur.
"Error: hsr: Only versions 0..1 are supported."
Fixes: ee1c27977284 ("net/hsr: Added support for HSR v1")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 09e91dbea0aa32be02d8877bd50490813de56b9a ]
The hsr module has been supporting the list and status command.
(HSR_C_GET_NODE_LIST and HSR_C_GET_NODE_STATUS)
These commands send node information to the user-space via generic netlink.
But, in the non-init_net namespace, these commands are not allowed
because .netnsok flag is false.
So, there is no way to get node information in the non-init_net namespace.
Fixes: f421436a591d ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ca19c70f5225771c05bcdcb832b4eb84d7271c5e ]
The hsr_get_node_list() is to send node addresses to the userspace.
If there are so many nodes, it could fail because of buffer size.
In order to avoid this failure, the restart routine is added.
Fixes: f421436a591d ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 173756b86803655d70af7732079b3aa935e6ab68 ]
hsr_get_node_{list/status}() are not under rtnl_lock() because
they are callback functions of generic netlink.
But they use __dev_get_by_index() without rtnl_lock().
So, it would use unsafe data.
In order to fix it, rcu_read_lock() and dev_get_by_index_rcu()
are used instead of __dev_get_by_index().
Fixes: f421436a591d ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3a303cfdd28d5f930a307c82e8a9d996394d5ebd ]
The port->hsr is used in the hsr_handle_frame(), which is a
callback of rx_handler.
hsr master and slaves are initialized in hsr_add_port().
This function initializes several pointers, which includes port->hsr after
registering rx_handler.
So, in the rx_handler routine, un-initialized pointer would be used.
In order to fix this, pointers should be initialized before
registering rx_handler.
Test commands:
ip netns del left
ip netns del right
modprobe -rv veth
modprobe -rv hsr
killall ping
modprobe hsr
ip netns add left
ip netns add right
ip link add veth0 type veth peer name veth1
ip link add veth2 type veth peer name veth3
ip link add veth4 type veth peer name veth5
ip link set veth1 netns left
ip link set veth3 netns right
ip link set veth4 netns left
ip link set veth5 netns right
ip link set veth0 up
ip link set veth2 up
ip link set veth0 address fc:00:00:00:00:01
ip link set veth2 address fc:00:00:00:00:02
ip netns exec left ip link set veth1 up
ip netns exec left ip link set veth4 up
ip netns exec right ip link set veth3 up
ip netns exec right ip link set veth5 up
ip link add hsr0 type hsr slave1 veth0 slave2 veth2
ip a a 192.168.100.1/24 dev hsr0
ip link set hsr0 up
ip netns exec left ip link add hsr1 type hsr slave1 veth1 slave2 veth4
ip netns exec left ip a a 192.168.100.2/24 dev hsr1
ip netns exec left ip link set hsr1 up
ip netns exec left ip n a 192.168.100.1 dev hsr1 lladdr \
fc:00:00:00:00:01 nud permanent
ip netns exec left ip n r 192.168.100.1 dev hsr1 lladdr \
fc:00:00:00:00:01 nud permanent
for i in {1..100}
do
ip netns exec left ping 192.168.100.1 &
done
ip netns exec left hping3 192.168.100.1 -2 --flood &
ip netns exec right ip link add hsr2 type hsr slave1 veth3 slave2 veth5
ip netns exec right ip a a 192.168.100.3/24 dev hsr2
ip netns exec right ip link set hsr2 up
ip netns exec right ip n a 192.168.100.1 dev hsr2 lladdr \
fc:00:00:00:00:02 nud permanent
ip netns exec right ip n r 192.168.100.1 dev hsr2 lladdr \
fc:00:00:00:00:02 nud permanent
for i in {1..100}
do
ip netns exec right ping 192.168.100.1 &
done
ip netns exec right hping3 192.168.100.1 -2 --flood &
while :
do
ip link add hsr0 type hsr slave1 veth0 slave2 veth2
ip a a 192.168.100.1/24 dev hsr0
ip link set hsr0 up
ip link del hsr0
done
Splat looks like:
[ 120.954938][ C0] general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1]I
[ 120.957761][ C0] KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
[ 120.959064][ C0] CPU: 0 PID: 1511 Comm: hping3 Not tainted 5.6.0-rc5+ #460
[ 120.960054][ C0] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 120.962261][ C0] RIP: 0010:hsr_addr_is_self+0x65/0x2a0 [hsr]
[ 120.963149][ C0] Code: 44 24 18 70 73 2f c0 48 c1 eb 03 48 8d 04 13 c7 00 f1 f1 f1 f1 c7 40 04 00 f2 f2 f2 4
[ 120.966277][ C0] RSP: 0018:ffff8880d9c09af0 EFLAGS: 00010206
[ 120.967293][ C0] RAX: 0000000000000006 RBX: 1ffff1101b38135f RCX: 0000000000000000
[ 120.968516][ C0] RDX: dffffc0000000000 RSI: ffff8880d17cb208 RDI: 0000000000000000
[ 120.969718][ C0] RBP: 0000000000000030 R08: ffffed101b3c0e3c R09: 0000000000000001
[ 120.972203][ C0] R10: 0000000000000001 R11: ffffed101b3c0e3b R12: 0000000000000000
[ 120.973379][ C0] R13: ffff8880aaf80100 R14: ffff8880aaf800f2 R15: ffff8880aaf80040
[ 120.974410][ C0] FS: 00007f58e693f740(0000) GS:ffff8880d9c00000(0000) knlGS:0000000000000000
[ 120.979794][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 120.980773][ C0] CR2: 00007ffcb8b38f29 CR3: 00000000afe8e001 CR4: 00000000000606f0
[ 120.981945][ C0] Call Trace:
[ 120.982411][ C0] <IRQ>
[ 120.982848][ C0] ? hsr_add_node+0x8c0/0x8c0 [hsr]
[ 120.983522][ C0] ? rcu_read_lock_held+0x90/0xa0
[ 120.984159][ C0] ? rcu_read_lock_sched_held+0xc0/0xc0
[ 120.984944][ C0] hsr_handle_frame+0x1db/0x4e0 [hsr]
[ 120.985597][ C0] ? hsr_nl_nodedown+0x2b0/0x2b0 [hsr]
[ 120.986289][ C0] __netif_receive_skb_core+0x6bf/0x3170
[ 120.992513][ C0] ? check_chain_key+0x236/0x5d0
[ 120.993223][ C0] ? do_xdp_generic+0x1460/0x1460
[ 120.993875][ C0] ? register_lock_class+0x14d0/0x14d0
[ 120.994609][ C0] ? __netif_receive_skb_one_core+0x8d/0x160
[ 120.995377][ C0] __netif_receive_skb_one_core+0x8d/0x160
[ 120.996204][ C0] ? __netif_receive_skb_core+0x3170/0x3170
[ ... ]
Reported-by: syzbot+fcf5dd39282ceb27108d@syzkaller.appspotmail.com
Fixes: c5a759117210 ("net/hsr: Use list_head (and rcu) instead of array for slave devices.")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3ed0a1d563903bdb4b4c36c58c4d9c1bcb23a6e6 upstream.
The supervision frame is L2 frame.
When supervision frame is created, hsr module doesn't set network header.
If tap routine is enabled, dev_queue_xmit_nit() is called and it checks
network_header. If network_header pointer wasn't set(or invalid),
it resets network_header and warns.
In order to avoid unnecessary warning message, resetting network_header
is needed.
Test commands:
ip netns add nst
ip link add veth0 type veth peer name veth1
ip link add veth2 type veth peer name veth3
ip link set veth1 netns nst
ip link set veth3 netns nst
ip link set veth0 up
ip link set veth2 up
ip link add hsr0 type hsr slave1 veth0 slave2 veth2
ip a a 192.168.100.1/24 dev hsr0
ip link set hsr0 up
ip netns exec nst ip link set veth1 up
ip netns exec nst ip link set veth3 up
ip netns exec nst ip link add hsr1 type hsr slave1 veth1 slave2 veth3
ip netns exec nst ip a a 192.168.100.2/24 dev hsr1
ip netns exec nst ip link set hsr1 up
tcpdump -nei veth0
Splat looks like:
[ 175.852292][ C3] protocol 88fb is buggy, dev veth0
Fixes: f421436a591d ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 675c8da049fd6556eb2d6cdd745fe812752f07a8 ]
When HSR interface is setup using ip link command, an annoying warning
appears with the trace as below:-
[ 203.019828] hsr_get_node: Non-HSR frame
[ 203.019833] Modules linked in:
[ 203.019848] CPU: 0 PID: 158 Comm: sd-resolve Tainted: G W 4.12.0-rc3-00052-g9fa6bf70 #2
[ 203.019853] Hardware name: Generic DRA74X (Flattened Device Tree)
[ 203.019869] [<c0110280>] (unwind_backtrace) from [<c010c2f4>] (show_stack+0x10/0x14)
[ 203.019880] [<c010c2f4>] (show_stack) from [<c04b9f64>] (dump_stack+0xac/0xe0)
[ 203.019894] [<c04b9f64>] (dump_stack) from [<c01374e8>] (__warn+0xd8/0x104)
[ 203.019907] [<c01374e8>] (__warn) from [<c0137548>] (warn_slowpath_fmt+0x34/0x44)
root@am57xx-evm:~# [ 203.019921] [<c0137548>] (warn_slowpath_fmt) from [<c081126c>] (hsr_get_node+0x148/0x170)
[ 203.019932] [<c081126c>] (hsr_get_node) from [<c0814240>] (hsr_forward_skb+0x110/0x7c0)
[ 203.019942] [<c0814240>] (hsr_forward_skb) from [<c0811d64>] (hsr_dev_xmit+0x2c/0x34)
[ 203.019954] [<c0811d64>] (hsr_dev_xmit) from [<c06c0828>] (dev_hard_start_xmit+0xc4/0x3bc)
[ 203.019963] [<c06c0828>] (dev_hard_start_xmit) from [<c06c13d8>] (__dev_queue_xmit+0x7c4/0x98c)
[ 203.019974] [<c06c13d8>] (__dev_queue_xmit) from [<c0782f54>] (ip6_finish_output2+0x330/0xc1c)
[ 203.019983] [<c0782f54>] (ip6_finish_output2) from [<c0788f0c>] (ip6_output+0x58/0x454)
[ 203.019994] [<c0788f0c>] (ip6_output) from [<c07b16cc>] (mld_sendpack+0x420/0x744)
As this is an expected path to hsr_get_node() with frame coming from
the master interface, add a check to ensure packet is not from the
master port and then warn.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove the unused but set variable master_dev in check_local_dest to fix
the following GCC warning when building with 'W=1':
net/hsr/hsr_forward.c: In function ‘check_local_dest’:
net/hsr/hsr_forward.c:303:21: warning: variable ‘master_dev’ set but not used [-Wunused-but-set-variable]
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
The function setup_timer combines the initialization of a timer with the
initialization of the timer's function and data fields. The mulitiline
code for timer initialization is now replaced with function setup_timer.
Also, quoting the mod_timer() function comment:
-> mod_timer() is a more efficient way to update the expire field of an
active timer (if the timer is inactive it will be activated).
Use setup_timer() and mod_timer() to setup and arm a timer, making the
code compact and aid readablity.
Signed-off-by: Muhammad Falak R Wani <falakreyaz@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Removed .type field from NLA to do proper length checking.
Reported by Daniel Borkmann and Julia Lawall.
Signed-off-by: Peter Heise <peter.heise@airbus.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds support for the newer version 1 of the HSR
networking standard. Version 0 is still default and the new
version has to be selected via iproute2.
Main changes are in the supervision frame handling and its
ethertype field.
Signed-off-by: Peter Heise <peter.heise@airbus.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
WARN_ON_ONCE() takes a condition, it doesn't take an error message. I
have converted this to WARN() instead.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To repeat:
$ sudo ip link del hsr0
BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
IP: [<ffffffff8187f495>] hsr_del_port+0x15/0xa0
etc...
Bug description:
As part of the hsr master device destruction, hsr_del_port() is called for each of
the hsr ports. At each such call, the master device is updated regarding features
and mtu. When the master device is freed before the slave interfaces, master will
be NULL in hsr_del_port(), which led to a NULL pointer dereference.
Additionally, dev_put() was called on the master device itself in hsr_del_port(),
causing a refcnt error.
A third bug in the same code path was that the rtnl lock was not taken before
hsr_del_port() was called as part of hsr_dev_destroy().
The reporter (Nicolas Dichtel) also said: "hsr_netdev_notify() supposes that the
port will always be available when the notification is for an hsr interface. It's
wrong. For example, netdev_wait_allrefs() may resend NETDEV_UNREGISTER.". As a
precaution against this, a check for port == NULL was added in hsr_dev_notify().
Reported-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Fixes: 51f3c605318b056a ("net/hsr: Move slave init to hsr_slave.c.")
Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
MacAddressB is an array (unsigned char MacAddressB[ETH_ALEN]) and is allocated
as a part of *node_dst (which is a struct hsr_node). So the condition is always
false.
Detected by Dan Carpenter.
Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
If none of the slave interfaces are specified, struct nlattr *data[] may
be NULL. Make sure to check for that.
While I'm at it, fix the horrible error messages displayed when only one
of the slave interfaces isn't specified.
Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes the separate paths for frames coming from the outside, and
frames sent from the HSR device, and instead makes all frames go through
hsr_forward_skb() in hsr_forward.c. This greatly improves code readability and
also opens up the possibility for future support of the HSR Interlink device
that is the basis for HSR RedBoxes and HSR QuadBoxes, as well as VLAN
compatibility.
Other improvements:
* A reduction in the number of times an skb is copied on machines without
HAVE_EFFICIENT_UNALIGNED_ACCESS, which improves throughput somewhat.
* Headers are now created using the standard eth_header(), and using the
standard hard_header_len.
* Each HSR slave now gets its own private skb, so slave-specific fields can be
correctly set.
Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also try to prevent some possible slave dereference race conditions. This is
finalized in the next patch, which abandons the slave array in favour of
a list_head list and list RCU.
Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also move the frame receive handler to hsr_slave.c.
Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use del_timer_sync to ensure that the timer is stopped on all CPUs before
the driver exists.
This change was suggested by Thomas Gleixner.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@r@
declarer name module_exit;
identifier ex;
@@
module_exit(ex);
@@
identifier r.ex;
@@
ex(...) {
<...
- del_timer
+ del_timer_sync
(...)
...>
}
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/wireless/ath/ath9k/recv.c
drivers/net/wireless/mwifiex/pcie.c
net/ipv6/sit.c
The SIT driver conflict consists of a bug fix being done by hand
in 'net' (missing u64_stats_init()) whilst in 'net-next' a helper
was created (netdev_alloc_pcpu_stats()) which takes care of this.
The two wireless conflicts were overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a sanity check and we never pass invalid values so this patch
doesn't change anything. However the node->time_in[] array has
HSR_MAX_SLAVE (2) elements and not HSR_MAX_DEV (3).
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It's slightly smaller/faster for some architectures.
Make sure def_multicast_addr is __aligned(2)
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The callback function of call_rcu() just calls a kfree(), so we
can use kfree_rcu() instead of call_rcu() + callback function.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
This implements the rtnl_link_ops fill_info routine for HSR.
Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
Register generic netlink multicast groups as an array with
the family and give them contiguous group IDs. Then instead
of passing the global group ID to the various functions that
send messages, pass the ID relative to the family - for most
families that's just 0 because the only have one group.
This avoids the list_head and ID in each group, adding a new
field for the mcast group ID offset to the family.
At the same time, this allows us to prevent abusing groups
again like the quota and dropmon code did, since we can now
check that a family only uses a group it owns.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This doesn't really change anything, but prepares for the
next patch that will change the APIs to pass the group ID
within the family, rather than the global group ID.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There's no need to unregister the multicast group if the
generic netlink family is registered immediately after.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As suggested by David Miller, make genl_register_family_with_ops()
a macro and pass only the array, evaluating ARRAY_SIZE() in the
macro, this is a little safer.
The openvswitch has some indirection, assing ops/n_ops directly in
that code. This might ultimately just assign the pointers in the
family initializations, saving the struct genl_family_and_ops and
code (once mcast groups are handled differently.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If 'hsr_get_node_data()' returns error, going directly to 'fail' label
doesn't free the memory pointed by 'skb_out'.
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that genl_ops are no longer modified in place when
registering, they can be made const. This patch was done
mostly with spatch:
@@
identifier ops;
@@
+const
struct genl_ops ops[] = {
...
};
(except the struct thing in net/openvswitch/datapath.c)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This simplifies the code since there's no longer a
need to have error handling in the registration.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
High-availability Seamless Redundancy ("HSR") provides instant failover
redundancy for Ethernet networks. It requires a special network topology where
all nodes are connected in a ring (each node having two physical network
interfaces). It is suited for applications that demand high availability and
very short reaction time.
HSR acts on the Ethernet layer, using a registered Ethernet protocol type to
send special HSR frames in both directions over the ring. The driver creates
virtual network interfaces that can be used just like any ordinary Linux
network interface, for IP/TCP/UDP traffic etc. All nodes in the network ring
must be HSR capable.
This code is a "best effort" to comply with the HSR standard as described in
IEC 62439-3:2010 (HSRv0).
Signed-off-by: Arvid Brodin <arvid.brodin@xdin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>