Some dst_ops (e.g. md_dst_ops)) doesn't set this handler. It may result to:
"BUG: unable to handle kernel NULL pointer dereference at (null)"
Let's add a helper to check if update_pmtu is available before calling it.
Fixes: 52a589d51f ("geneve: update skb dst pmtu on tx path")
Fixes: a93bf0ff44 ("vxlan: update skb dst pmtu on tx path")
CC: Roman Kapl <code@rkapl.cz>
CC: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a tcp socket is closed, if it detects that its net namespace is
exiting, close immediately and do not wait for FIN sequence.
For normal sockets, a reference is taken to their net namespace, so it will
never exit while the socket is open. However, kernel sockets do not take a
reference to their net namespace, so it may begin exiting while the kernel
socket is still open. In this case if the kernel socket is a tcp socket,
it will stay open trying to complete its close sequence. The sock's dst(s)
hold a reference to their interface, which are all transferred to the
namespace's loopback interface when the real interfaces are taken down.
When the namespace tries to take down its loopback interface, it hangs
waiting for all references to the loopback interface to release, which
results in messages like:
unregister_netdevice: waiting for lo to become free. Usage count = 1
These messages continue until the socket finally times out and closes.
Since the net namespace cleanup holds the net_mutex while calling its
registered pernet callbacks, any new net namespace initialization is
blocked until the current net namespace finishes exiting.
After this change, the tcp socket notices the exiting net namespace, and
closes immediately, releasing its dst(s) and their reference to the
loopback interface, which lets the net namespace continue exiting.
Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1711407
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=97811
Signed-off-by: Dan Streetman <ddstreet@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
TCF_LAYER_LINK and TCF_LAYER_NETWORK returned the same pointer as
skb->data points to the network header.
Use skb_mac_header instead.
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 513674b5a2 ("net: reevalulate autoflowlabel setting after
sysctl setting") removed the initialisation of
ipv6_pinfo::autoflowlabel and added a second flag to indicate
whether this field or the net namespace default should be used.
The getsockopt() handling for this case was not updated, so it
currently returns 0 for all sockets for which IPV6_AUTOFLOWLABEL is
not explicitly enabled. Fix it to return the effective value, whether
that has been set at the socket or net namespace level.
Fixes: 513674b5a2 ("net: reevalulate autoflowlabel setting after sysctl ...")
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
While working on fixing another bug, I ran into the following panic
on arm64 by simply attaching clsact qdisc, adding a filter and running
traffic on ingress to it:
[...]
[ 178.188591] Unable to handle kernel read from unreadable memory at virtual address 810fb501f000
[ 178.197314] Mem abort info:
[ 178.200121] ESR = 0x96000004
[ 178.203168] Exception class = DABT (current EL), IL = 32 bits
[ 178.209095] SET = 0, FnV = 0
[ 178.212157] EA = 0, S1PTW = 0
[ 178.215288] Data abort info:
[ 178.218175] ISV = 0, ISS = 0x00000004
[ 178.222019] CM = 0, WnR = 0
[ 178.224997] user pgtable: 4k pages, 48-bit VAs, pgd = 0000000023cb3f33
[ 178.231531] [0000810fb501f000] *pgd=0000000000000000
[ 178.236508] Internal error: Oops: 96000004 [#1] SMP
[...]
[ 178.311855] CPU: 73 PID: 2497 Comm: ping Tainted: G W 4.15.0-rc7+ #5
[ 178.319413] Hardware name: FOXCONN R2-1221R-A4/C2U4N_MB, BIOS G31FB18A 03/31/2017
[ 178.326887] pstate: 60400005 (nZCv daif +PAN -UAO)
[ 178.331685] pc : __netif_receive_skb_core+0x49c/0xac8
[ 178.336728] lr : __netif_receive_skb+0x28/0x78
[ 178.341161] sp : ffff00002344b750
[ 178.344465] x29: ffff00002344b750 x28: ffff810fbdfd0580
[ 178.349769] x27: 0000000000000000 x26: ffff000009378000
[...]
[ 178.418715] x1 : 0000000000000054 x0 : 0000000000000000
[ 178.424020] Process ping (pid: 2497, stack limit = 0x000000009f0a3ff4)
[ 178.430537] Call trace:
[ 178.432976] __netif_receive_skb_core+0x49c/0xac8
[ 178.437670] __netif_receive_skb+0x28/0x78
[ 178.441757] process_backlog+0x9c/0x160
[ 178.445584] net_rx_action+0x2f8/0x3f0
[...]
Reason is that sch_ingress and sch_clsact are doing mini_qdisc_pair_init()
which sets up miniq pointers to cpu_{b,q}stats from the underlying qdisc.
Problem is that this cannot work since they are actually set up right after
the qdisc ->init() callback in qdisc_create(), so first packet going into
sch_handle_ingress() tries to call mini_qdisc_bstats_cpu_update() and we
therefore panic.
In order to fix this, allocation of {b,q}stats needs to happen before we
call into ->init(). In net-next, there's already such option through commit
d59f5ffa59 ("net: sched: a dflt qdisc may be used with per cpu stats").
However, the bug needs to be fixed in net still for 4.15. Thus, include
these bits to reduce any merge churn and reuse the static_flags field to
set TCQ_F_CPUSTATS, and remove the allocation from qdisc_create() since
there is no other user left. Prashant Bhole ran into the same issue but
for net-next, thus adding him below as well as co-author. Same issue was
also reported by Sandipan Das when using bcc.
Fixes: 46209401f8 ("net: core: introduce mini_Qdisc and eliminate usage of tp->q for clsact fastpath")
Reference: https://lists.iovisor.org/pipermail/iovisor-dev/2018-January/001190.html
Reported-by: Sandipan Das <sandipan@linux.vnet.ibm.com>
Co-authored-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Co-authored-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
Johannes Berg says:
====================
More fixes:
* hwsim:
- properly flush deletion works at module unload
- validate # of channels passed from userspace
* cfg80211:
- fix RCU locking regression
- initialize on-stack channel data for nl80211 event
- check dev_set_name() return value
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Map all lookup neigh keys to INADDR_ANY for loopback/point-to-point devices
to avoid making an entry for every remote ip the device needs to talk to.
This used the be the old behavior but became broken in a263b30936
(ipv4: Make neigh lookups directly in output packet path) and later removed
in 0bb4087cbe (ipv4: Fix neigh lookup keying over loopback/point-to-point
devices) because it was broken.
Signed-off-by: Jim Westfall <jwestfall@surrealistic.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
sendfile() calls can hang endless with using Kernel TLS if a socket error occurs.
Socket error codes must be inverted by Kernel TLS before returning because
they are stored with positive sign. If returned non-inverted they are
interpreted as number of bytes sent, causing endless looping of the
splice mechanic behind sendfile().
Signed-off-by: Robert Hering <r.hering@avm.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
When creating a new radio on the fly, hwsim allows this
to be done with an arbitrary number of channels, but
cfg80211 only supports a limited number of simultaneous
channels, leading to a warning.
Fix this by validating the number - this requires moving
the define for the maximum out to a visible header file.
Reported-by: syzbot+8dd9051ff19940290931@syzkaller.appspotmail.com
Fixes: b59ec8dd43 ("mac80211_hwsim: fix number of channels in interface combinations")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
syzbot reported a hang involving SCTP, on which it kept flooding dmesg
with the message:
[ 246.742374] sctp: sctp_transport_update_pmtu: Reported pmtu 508 too
low, using default minimum of 512
That happened because whenever SCTP hits an ICMP Frag Needed, it tries
to adjust to the new MTU and triggers an immediate retransmission. But
it didn't consider the fact that MTUs smaller than the SCTP minimum MTU
allowed (512) would not cause the PMTU to change, and issued the
retransmission anyway (thus leading to another ICMP Frag Needed, and so
on).
As IPv4 (ip_rt_min_pmtu=556) and IPv6 (IPV6_MIN_MTU=1280) minimum MTU
are higher than that, sctp_transport_update_pmtu() is changed to
re-fetch the PMTU that got set after our request, and with that, detect
if there was an actual change or not.
The fix, thus, skips the immediate retransmission if the received ICMP
resulted in no change, in the hope that SCTP will select another path.
Note: The value being used for the minimum MTU (512,
SCTP_DEFAULT_MINSEGMENT) is not right and instead it should be (576,
SCTP_MIN_PMTU), but such change belongs to another patch.
Changes from v1:
- do not disable PMTU discovery, in the light of commit
06ad391919 ("[SCTP] Don't disable PMTU discovery when mtu is small")
and as suggested by Xin Long.
- changed the way to break the rtx loop by detecting if the icmp
resulted in a change or not
Changes from v2:
none
See-also: https://lkml.org/lkml/2017/12/22/811
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This allows checking socket lock ownership with producing lockdep
warnings.
Signed-off-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Steffen Klassert says:
====================
pull request (net): ipsec 2017-12-22
1) Check for valid id proto in validate_tmpl(), otherwise
we may trigger a warning in xfrm_state_fini().
From Cong Wang.
2) Fix a typo on XFRMA_OUTPUT_MARK policy attribute.
From Michal Kubecek.
3) Verify the state is valid when encap_type < 0,
otherwise we may crash on IPsec GRO .
From Aviv Heller.
4) Fix stack-out-of-bounds read on socket policy lookup.
We access the flowi of the wrong address family in the
IPv4 mapped IPv6 case, fix this by catching address
family missmatches before we do the lookup.
5) fix xfrm_do_migrate() with AEAD to copy the geniv
field too. Otherwise the state is not fully initialized
and migration fails. From Antony Antony.
6) Fix stack-out-of-bounds with misconfigured transport
mode policies. Our policy template validation is not
strict enough. It is possible to configure policies
with transport mode template where the address family
of the template does not match the selectors address
family. Fix this by refusing such a configuration,
address family can not change on transport mode.
7) Fix a policy reference leak when reusing pcpu xdst
entry. From Florian Westphal.
8) Reinject transport-mode packets through tasklet,
otherwise it is possible to reate a recursion
loop. From Herbert Xu.
Please pull or let me know if there are problems.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
cls_bpf used to take care of tracking what offload state a filter
is in, i.e. it would track if offload request succeeded or not.
This information would then be used to issue correct requests to
the driver, e.g. requests for statistics only on offloaded filters,
removing only filters which were offloaded, using add instead of
replace if previous filter was not added etc.
This tracking of offload state no longer functions with the new
callback infrastructure. There could be multiple entities trying
to offload the same filter.
Throw out all the tracking and corresponding commands and simply
pass to the drivers both old and new bpf program. Drivers will
have to deal with offload state tracking by themselves.
Fixes: 3f7889c4c7 ("net: sched: cls_bpf: call block callbacks for offload")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Johannes Berg says:
====================
A few more fixes:
* hwsim:
- set To-DS bit in some frames missing it
- fix sleeping in atomic
* nl80211:
- doc cleanup
- fix locking in an error path
* build:
- don't append to created certs C files
- ship certificate pre-hexdumped
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit ca986ad9bc (nl80211: allow multiple active scheduled scan
requests) removed WIPHY_FLAG_SUPPORTS_SCHED_SCAN but left the kerneldoc
description in place, leading to this docs-build warning:
./include/net/cfg80211.h:3278: warning: Excess enum value
'WIPHY_FLAG_SUPPORTS_SCHED_SCAN' description in 'wiphy_flags'
Remove the line and gain a bit of peace.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This is an old bugbear of mine:
https://www.mail-archive.com/netdev@vger.kernel.org/msg03894.html
By crafting special packets, it is possible to cause recursion
in our kernel when processing transport-mode packets at levels
that are only limited by packet size.
The easiest one is with DNAT, but an even worse one is where
UDP encapsulation is used in which case you just have to insert
an UDP encapsulation header in between each level of recursion.
This patch avoids this problem by reinjecting tranport-mode packets
through a tasklet.
Fixes: b05e106698 ("[IPV4/6]: Netfilter IPsec input hooks")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Qdiscs can be offloaded to HW, but current implementation isn't uniform.
Instead, qdiscs either pass information about offload status via their
TCA_OPTIONS or omit it altogether.
Introduce a new attribute - TCA_HW_OFFLOAD that would form a uniform
uAPI for the offloading status of qdiscs.
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IPv4 stack reacts to changes to small MTU, by disabling itself under
RTNL.
But there is a window where threads not using RTNL can see a wrong
device mtu. This can lead to surprises, in igmp code where it is
assumed the mtu is suitable.
Fix this by reading device mtu once and checking IPv4 minimal MTU.
This patch adds missing IPV4_MIN_MTU define, to not abuse
ETH_MIN_MTU anymore.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
guehdr struct is used to build or parse gue packets, which
are always in big endian. It's better to define all guehdr
members as __beXX types.
Also, in validate_gue_flags it's not good to use a __be32
variable for both Standard flags(__be16) and Private flags
(__be32), and pass it to other funcions.
This patch could fix a bunch of sparse warnings from fou.
Fixes: 5024c33ac3 ("gue: Add infrastructure for flags and options")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Mark tcp_sock during a SACK reneging event and invalidate rate samples
while marked. Such rate samples may overestimate bw by including packets
that were SACKed before reneging.
< ack 6001 win 10000 sack 7001:38001
< ack 7001 win 0 sack 8001:38001 // Reneg detected
> seq 7001:8001 // RTO, SACK cleared.
< ack 38001 win 10000
In above example the rate sample taken after the last ack will count
7001-38001 as delivered while the actual delivery rate likely could
be much lower i.e. 7001-8001.
This patch adds a new field tcp_sock.sack_reneg and marks it when we
declare SACK reneging and entering TCP_CA_Loss, and unmarks it after
the last rate sample was taken before moving back to TCP_CA_Open. This
patch also invalidates rate samples taken while tcp_sock.is_sack_reneg
is set.
Fixes: b9f64820fb ("tcp: track data delivery rate for a TCP connection")
Signed-off-by: Yousuk Seung <ysseung@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Priyaranjan Jha <priyarjha@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexander Potapenko reported use of uninitialized memory [1]
This happens when inserting a request socket into TCP ehash,
in __sk_nulls_add_node_rcu(), since sk_reuseport is not initialized.
Bug was added by commit d894ba18d4 ("soreuseport: fix ordering for
mixed v4/v6 sockets")
Note that d296ba60d8 ("soreuseport: Resolve merge conflict for v4/v6
ordering fix") missed the opportunity to get rid of
hlist_nulls_add_tail_rcu() :
Both UDP sockets and TCP/DCCP listeners no longer use
__sk_nulls_add_node_rcu() for their hash insertion.
Since all other sockets have unique 4-tuple, the reuseport status
has no special meaning, so we can always use hlist_nulls_add_head_rcu()
for them and save few cycles/instructions.
[1]
==================================================================
BUG: KMSAN: use of uninitialized memory in inet_ehash_insert+0xd40/0x1050
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.13.0+ #3288
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:16
dump_stack+0x185/0x1d0 lib/dump_stack.c:52
kmsan_report+0x13f/0x1c0 mm/kmsan/kmsan.c:1016
__msan_warning_32+0x69/0xb0 mm/kmsan/kmsan_instr.c:766
__sk_nulls_add_node_rcu ./include/net/sock.h:684
inet_ehash_insert+0xd40/0x1050 net/ipv4/inet_hashtables.c:413
reqsk_queue_hash_req net/ipv4/inet_connection_sock.c:754
inet_csk_reqsk_queue_hash_add+0x1cc/0x300 net/ipv4/inet_connection_sock.c:765
tcp_conn_request+0x31e7/0x36f0 net/ipv4/tcp_input.c:6414
tcp_v4_conn_request+0x16d/0x220 net/ipv4/tcp_ipv4.c:1314
tcp_rcv_state_process+0x42a/0x7210 net/ipv4/tcp_input.c:5917
tcp_v4_do_rcv+0xa6a/0xcd0 net/ipv4/tcp_ipv4.c:1483
tcp_v4_rcv+0x3de0/0x4ab0 net/ipv4/tcp_ipv4.c:1763
ip_local_deliver_finish+0x6bb/0xcb0 net/ipv4/ip_input.c:216
NF_HOOK ./include/linux/netfilter.h:248
ip_local_deliver+0x3fa/0x480 net/ipv4/ip_input.c:257
dst_input ./include/net/dst.h:477
ip_rcv_finish+0x6fb/0x1540 net/ipv4/ip_input.c:397
NF_HOOK ./include/linux/netfilter.h:248
ip_rcv+0x10f6/0x15c0 net/ipv4/ip_input.c:488
__netif_receive_skb_core+0x36f6/0x3f60 net/core/dev.c:4298
__netif_receive_skb net/core/dev.c:4336
netif_receive_skb_internal+0x63c/0x19c0 net/core/dev.c:4497
napi_skb_finish net/core/dev.c:4858
napi_gro_receive+0x629/0xa50 net/core/dev.c:4889
e1000_receive_skb drivers/net/ethernet/intel/e1000/e1000_main.c:4018
e1000_clean_rx_irq+0x1492/0x1d30
drivers/net/ethernet/intel/e1000/e1000_main.c:4474
e1000_clean+0x43aa/0x5970 drivers/net/ethernet/intel/e1000/e1000_main.c:3819
napi_poll net/core/dev.c:5500
net_rx_action+0x73c/0x1820 net/core/dev.c:5566
__do_softirq+0x4b4/0x8dd kernel/softirq.c:284
invoke_softirq kernel/softirq.c:364
irq_exit+0x203/0x240 kernel/softirq.c:405
exiting_irq+0xe/0x10 ./arch/x86/include/asm/apic.h:638
do_IRQ+0x15e/0x1a0 arch/x86/kernel/irq.c:263
common_interrupt+0x86/0x86
Fixes: d894ba18d4 ("soreuseport: fix ordering for mixed v4/v6 sockets")
Fixes: d296ba60d8 ("soreuseport: Resolve merge conflict for v4/v6 ordering fix")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Alexander Potapenko <glider@google.com>
Acked-by: Craig Gallek <kraig@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Check the qmin & qmax values doesn't overflow for the given Wlog value.
Check that qmin <= qmax.
Fixes: a783474591 ("[PKT_SCHED]: Generic RED layer")
Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Do not allow delta value to be zero since it is used as a divisor.
Fixes: 8af2a218de ("sch_red: Adaptative RED AQM")
Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After this fix : ("tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()"),
socket lookups happen while skb->cb[] has not been mangled yet by TCP.
Fixes: a04a480d43 ("net: Require exact match for TCP socket lookups if dif is l3mdev")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
