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Commit 9ce33e46531d ("neighbour: support for NTF_EXT_LEARNED flag")
added support for NTF_EXT_LEARNED for neighbour entries.
NTF_EXT_LEARNED entries are neigh entries managed by control
plane (eg: Ethernet VPN implementation in FRR routing suite).
Periodic gc already excludes these entries. This patch extends
it to forced gc which the earlier patch missed.
Fixes: 9ce33e46531d ("neighbour: support for NTF_EXT_LEARNED flag")
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When sysfs_create_group fails, the lack of error-handling code may
cause unexpected results.
This patch adds error-handling code after calling sysfs_create_group.
Signed-off-by: Zhouyang Jia <jiazhouyang09@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
Two tls fixes
First one is syzkaller trigered uaf and second one noticed
while writing test code with tls ulp. For details please see
individual patches.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Guillaume Nault says:
====================
l2tp: l2tp_ppp must ignore non-PPP sessions
The original L2TP code was written for version 2 of the protocol, which
could only carry PPP sessions. Then L2TPv3 generalised the protocol so that
it could transport different kinds of pseudo-wires. But parts of the
l2tp_ppp module still break in presence of non-PPP sessions.
Assuming L2TPv2 tunnels can only transport PPP sessions is right, but
l2tp_netlink failed to ensure that (fixed in patch 1).
When retrieving a session from an arbitrary tunnel, l2tp_ppp needs to
filter out non-PPP sessions (last occurrence fixed in patch 2).
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Current behavior in tls_sw_recvmsg() is to wait for incoming tls
messages and copy up to exactly len bytes of data that the user
provided. This is problematic in the sense that i) if no packet
is currently queued in strparser we keep waiting until one has been
processed and pushed into tls receive layer for tls_wait_data() to
wake up and push the decrypted bits to user space. Given after
tls decryption, we're back at streaming data, use sock_rcvlowat()
hint from tcp socket instead. Retain current behavior with MSG_WAITALL
flag and otherwise use the hint target for breaking the loop and
returning to application. This is done if currently no ctx->recv_pkt
is ready, otherwise continue to process it from our strparser
backlog.
Fixes: c46234ebb4d1 ("tls: RX path for ktls")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ido Schimmel says:
====================
mlxsw: IPv6 and reference counting fixes
The first three patches fix a mismatch between the new IPv6 behavior
introduced in commit f34436a43092 ("net/ipv6: Simplify route replace and
appending into multipath route") and mlxsw. The patches allow the driver
to support multipathing in IPv6 overlays with GRE tunnel devices. A
selftest will be submitted when net-next opens.
The last patch fixes a reference count problem of the port_vlan struct.
I plan to simplify the code in net-next, so that reference counting is
not necessary anymore.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
pppol2tp_tunnel_ioctl() can act on an L2TPv3 tunnel, in which case
'session' may be an Ethernet pseudo-wire.
However, pppol2tp_session_ioctl() expects a PPP pseudo-wire, as it
assumes l2tp_session_priv() points to a pppol2tp_session structure. For
an Ethernet pseudo-wire l2tp_session_priv() points to an l2tp_eth_sess
structure instead, making pppol2tp_session_ioctl() access invalid
memory.
Fixes: d9e31d17ceba ("l2tp: Add L2TP ethernet pseudowire support")
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
syzkaller managed to trigger a use-after-free in tls like the
following:
BUG: KASAN: use-after-free in tls_push_record.constprop.15+0x6a2/0x810 [tls]
Write of size 1 at addr ffff88037aa08000 by task a.out/2317
CPU: 3 PID: 2317 Comm: a.out Not tainted 4.17.0+ #144
Hardware name: LENOVO 20FBCTO1WW/20FBCTO1WW, BIOS N1FET47W (1.21 ) 11/28/2016
Call Trace:
dump_stack+0x71/0xab
print_address_description+0x6a/0x280
kasan_report+0x258/0x380
? tls_push_record.constprop.15+0x6a2/0x810 [tls]
tls_push_record.constprop.15+0x6a2/0x810 [tls]
tls_sw_push_pending_record+0x2e/0x40 [tls]
tls_sk_proto_close+0x3fe/0x710 [tls]
? tcp_check_oom+0x4c0/0x4c0
? tls_write_space+0x260/0x260 [tls]
? kmem_cache_free+0x88/0x1f0
inet_release+0xd6/0x1b0
__sock_release+0xc0/0x240
sock_close+0x11/0x20
__fput+0x22d/0x660
task_work_run+0x114/0x1a0
do_exit+0x71a/0x2780
? mm_update_next_owner+0x650/0x650
? handle_mm_fault+0x2f5/0x5f0
? __do_page_fault+0x44f/0xa50
? mm_fault_error+0x2d0/0x2d0
do_group_exit+0xde/0x300
__x64_sys_exit_group+0x3a/0x50
do_syscall_64+0x9a/0x300
? page_fault+0x8/0x30
entry_SYSCALL_64_after_hwframe+0x44/0xa9
This happened through fault injection where aead_req allocation in
tls_do_encryption() eventually failed and we returned -ENOMEM from
the function. Turns out that the use-after-free is triggered from
tls_sw_sendmsg() in the second tls_push_record(). The error then
triggers a jump to waiting for memory in sk_stream_wait_memory()
resp. returning immediately in case of MSG_DONTWAIT. What follows is
the trim_both_sgl(sk, orig_size), which drops elements from the sg
list added via tls_sw_sendmsg(). Now the use-after-free gets triggered
when the socket is being closed, where tls_sk_proto_close() callback
is invoked. The tls_complete_pending_work() will figure that there's
a pending closed tls record to be flushed and thus calls into the
tls_push_pending_closed_record() from there. ctx->push_pending_record()
is called from the latter, which is the tls_sw_push_pending_record()
from sw path. This again calls into tls_push_record(). And here the
tls_fill_prepend() will panic since the buffer address has been freed
earlier via trim_both_sgl(). One way to fix it is to move the aead
request allocation out of tls_do_encryption() early into tls_push_record().
This means we don't prep the tls header and advance state to the
TLS_PENDING_CLOSED_RECORD before allocation which could potentially
fail happened. That fixes the issue on my side.
Fixes: 3c4d7559159b ("tls: kernel TLS support")
Reported-by: syzbot+5c74af81c547738e1684@syzkaller.appspotmail.com
Reported-by: syzbot+709f2810a6a05f11d4d3@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Johannes Berg says:
====================
A handful of fixes:
* missing RCU grace period enforcement led to drivers freeing
data structures before; fix from Dedy Lansky.
* hwsim module init error paths were messed up; fixed it myself
after a report from Colin King (who had sent a partial patch)
* kernel-doc tag errors; fix from Luca Coelho
* initialize the on-stack sinfo data structure when getting
station information; fix from Sven Eckelmann
* TXQ state dumping is now done from init, and when TXQs aren't
initialized yet at that point, bad things happen, move the
initialization; fix from Toke Høiland-Jørgensen.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Switchdev notifications for addition of SWITCHDEV_OBJ_ID_PORT_VLAN are
distributed not only on clean addition, but also when flags on an
existing VLAN are changed. mlxsw_sp_bridge_port_vlan_add() calls
mlxsw_sp_port_vlan_get() to get at the port_vlan in question, which
implicitly references the object. This then leads to discrepancies in
reference counting when the VLAN is removed. spectrum.c warns about the
problem when the module is removed:
[13578.493090] WARNING: CPU: 0 PID: 2454 at drivers/net/ethernet/mellanox/mlxsw/spectrum.c:2973 mlxsw_sp_port_remove+0xfd/0x110 [mlxsw_spectrum]
[...]
[13578.627106] Call Trace:
[13578.629617] mlxsw_sp_fini+0x2a/0xe0 [mlxsw_spectrum]
[13578.634748] mlxsw_core_bus_device_unregister+0x3e/0x130 [mlxsw_core]
[13578.641290] mlxsw_pci_remove+0x13/0x40 [mlxsw_pci]
[13578.646238] pci_device_remove+0x31/0xb0
[13578.650244] device_release_driver_internal+0x14f/0x220
[13578.655562] driver_detach+0x32/0x70
[13578.659183] bus_remove_driver+0x47/0xa0
[13578.663134] pci_unregister_driver+0x1e/0x80
[13578.667486] mlxsw_sp_module_exit+0xc/0x3fa [mlxsw_spectrum]
[13578.673207] __x64_sys_delete_module+0x13b/0x1e0
[13578.677888] ? exit_to_usermode_loop+0x78/0x80
[13578.682374] do_syscall_64+0x39/0xe0
[13578.685976] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fix by putting the port_vlan when mlxsw_sp_port_vlan_bridge_join()
determines it's a flag-only change.
Fixes: b3529af6bb0d ("spectrum: Reference count VLAN entries")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The /proc/net/pppol2tp handlers (pppol2tp_seq_*()) iterate over all
L2TPv2 tunnels, and rightfully expect that only PPP sessions can be
found there. However, l2tp_netlink accepts creating Ethernet sessions
regardless of the underlying tunnel version.
This confuses pppol2tp_seq_session_show(), which expects that
l2tp_session_priv() returns a pppol2tp_session structure. When the
session is an Ethernet pseudo-wire, a struct l2tp_eth_sess is returned
instead. This leads to invalid memory access when
pppol2tp_session_get_sock() later tries to dereference ps->sk.
Fixes: d9e31d17ceba ("l2tp: Add L2TP ethernet pseudowire support")
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
stmmac reception handler calls stmmac_rx_vlan() to strip the vlan before
calling napi_gro_receive().
The function assumes VLAN tagged frames are always tagged with
802.1Q protocol, and assigns ETH_P_8021Q to the skb by hard-coding
the parameter on call to __vlan_hwaccel_put_tag() .
This causes packets not to be passed to the VLAN slave if it was created
with 802.1AD protocol
(ip link add link eth0 eth0.100 type vlan proto 802.1ad id 100).
This fix passes the protocol from the VLAN header into
__vlan_hwaccel_put_tag() instead of using the hard-coded value of
ETH_P_8021Q.
NETIF_F_HW_VLAN_STAG_RX check was added and the strip action is now
dependent on the correct combination of features and the detected vlan tag.
NETIF_F_HW_VLAN_STAG_RX feature was added to be in line with the driver
actual abilities.
Signed-off-by: Elad Nachman <eladn@gilat.com>
Reviewed-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
Callers of cfg80211_unregister_wdev can free the wdev object
immediately after this function returns. This may crash the kernel
because this wdev object is still in use by other threads.
Add synchronize_rcu() after list_del_rcu to make sure wdev object can
be safely freed.
Signed-off-by: Dedy Lansky <dlansky@codeaurora.org>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Commit f34436a43092 ("net/ipv6: Simplify route replace and appending
into multipath route") changed the IPv6 route replace logic so that the
first matching route (i.e., same metric) is replaced.
Have mlxsw replace the first matching route as well.
Fixes: f34436a43092 ("net/ipv6: Simplify route replace and appending into multipath route")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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