linux-stable.git/net, branch v5.16.3

sch_api: Don't skip qdisc attach on ingress

2022-01-27T11:03:03+00:00

commit de2d807b294d3d2ce5e59043ae2634016765d076 upstream.

The attach callback of struct Qdisc_ops is used by only a few qdiscs:
mq, mqprio and htb. qdisc_graft() contains the following logic
(pseudocode):

    if (!qdisc->ops->attach) {
        if (ingress)
            do ingress stuff;
        else
            do egress stuff;
    }
    if (!ingress) {
        ...
        if (qdisc->ops->attach)
            qdisc->ops->attach(qdisc);
    } else {
        ...
    }

As we see, the attach callback is not called if the qdisc is being
attached to ingress (TC_H_INGRESS). That wasn't a problem for mq and
mqprio, since they contain a check that they are attached to TC_H_ROOT,
and they can't be attached to TC_H_INGRESS anyway.

However, the commit cited below added the attach callback to htb. It is
needed for the hardware offload, but in the non-offload mode it
simulates the "do egress stuff" part of the pseudocode above. The
problem is that when htb is attached to ingress, neither "do ingress
stuff" nor attach() is called. It results in an inconsistency, and the
following message is printed to dmesg:

unregister_netdevice: waiting for lo to become free. Usage count = 2

This commit addresses the issue by running "do ingress stuff" in the
ingress flow even in the attach callback is present, which is fine,
because attach isn't going to be called afterwards.

The bug was found by syzbot and reported by Eric.

Fixes: d03b195b5aa0 ("sch_htb: Hierarchical QoS hardware offload")
Signed-off-by: Maxim Mikityanskiy 
Reported-by: Eric Dumazet 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net_sched: restore "mpu xxx" handling

2022-01-27T11:03:01+00:00

commit fb80445c438c78b40b547d12b8d56596ce4ccfeb upstream.

commit 56b765b79e9a ("htb: improved accuracy at high rates") broke
"overhead X", "linklayer atm" and "mpu X" attributes.

"overhead X" and "linklayer atm" have already been fixed. This restores
the "mpu X" handling, as might be used by DOCSIS or Ethernet shaping:

    tc class add ... htb rate X overhead 4 mpu 64

The code being fixed is used by htb, tbf and act_police. Cake has its
own mpu handling. qdisc_calculate_pkt_len still uses the size table
containing values adjusted for mpu by user space.

iproute2 tc has always passed mpu into the kernel via a tc_ratespec
structure, but the kernel never directly acted on it, merely stored it
so that it could be read back by `tc class show`.

Rather, tc would generate length-to-time tables that included the mpu
(and linklayer) in their construction, and the kernel used those tables.

Since v3.7, the tables were no longer used. Along with "mpu", this also
broke "overhead" and "linklayer" which were fixed in 01cb71d2d47b
("net_sched: restore "overhead xxx" handling", v3.10) and 8a8e3d84b171
("net_sched: restore "linklayer atm" handling", v3.11).

"overhead" was fixed by simply restoring use of tc_ratespec::overhead -
this had originally been used by the kernel but was initially omitted
from the new non-table-based calculations.

"linklayer" had been handled in the table like "mpu", but the mode was
not originally passed in tc_ratespec. The new implementation was made to
handle it by getting new versions of tc to pass the mode in an extended
tc_ratespec, and for older versions of tc the table contents were analysed
at load time to deduce linklayer.

As "mpu" has always been given to the kernel in tc_ratespec,
accompanying the mpu-based table, we can restore system functionality
with no userspace change by making the kernel act on the tc_ratespec
value.

Fixes: 56b765b79e9a ("htb: improved accuracy at high rates")
Signed-off-by: Kevin Bracey 
Cc: Eric Dumazet 
Cc: Jiri Pirko 
Cc: Vimalkumar 
Link: https://lore.kernel.org/r/20220112170210.1014351-1-kevin@bracey.fi
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

net: fix sock_timestamping_bind_phc() to release device

2022-01-27T11:03:01+00:00

commit 2a4d75bfe41232608f5596a6d1369f92ccb20817 upstream.

Don't forget to release the device in sock_timestamping_bind_phc() after
it was used to get the vclock indices.

Fixes: d463126e23f1 ("net: sock: extend SO_TIMESTAMPING for PHC binding")
Signed-off-by: Miroslav Lichvar 
Cc: Yangbo Lu 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

devlink: Remove misleading internal_flags from health reporter dump

2022-01-27T11:03:01+00:00

commit e9538f8270db24d272659e15841854c7ea11119e upstream.

DEVLINK_CMD_HEALTH_REPORTER_DUMP_GET command doesn't have .doit callback
and has no use in internal_flags at all. Remove this misleading assignment.

Fixes: e44ef4e4516c ("devlink: Hang reporter's dump method on a dumpit cb")
Signed-off-by: Leon Romanovsky 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

gre: Don't accidentally set RTO_ONLINK in gre_fill_metadata_dst()

2022-01-27T11:02:59+00:00

commit f7716b318568b22fbf0e3be99279a979e217cf71 upstream.

Mask the ECN bits before initialising ->flowi4_tos. The tunnel key may
have the last ECN bit set, which will interfere with the route lookup
process as ip_route_output_key_hash() interpretes this bit specially
(to restrict the route scope).

Found by code inspection, compile tested only.

Fixes: 962924fa2b7a ("ip_gre: Refactor collect metatdata mode tunnel xmit to ip_md_tunnel_xmit")
Signed-off-by: Guillaume Nault 
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

xfrm: Don't accidentally set RTO_ONLINK in decode_session4()

2022-01-27T11:02:59+00:00

commit 23e7b1bfed61e301853b5e35472820d919498278 upstream.

Similar to commit 94e2238969e8 ("xfrm4: strip ECN bits from tos field"),
clear the ECN bits from iph->tos when setting ->flowi4_tos.
This ensures that the last bit of ->flowi4_tos is cleared, so
ip_route_output_key_hash() isn't going to restrict the scope of the
route lookup.

Use ~INET_ECN_MASK instead of IPTOS_RT_MASK, because we have no reason
to clear the high order bits.

Found by code inspection, compile tested only.

Fixes: 4da3089f2b58 ("[IPSEC]: Use TOS when doing tunnel lookups")
Signed-off-by: Guillaume Nault 
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

netns: add schedule point in ops_exit_list()

2022-01-27T11:02:59+00:00

commit 2836615aa22de55b8fca5e32fe1b27a67cda625e upstream.

When under stress, cleanup_net() can have to dismantle
netns in big numbers. ops_exit_list() currently calls
many helpers [1] that have no schedule point, and we can
end up with soft lockups, particularly on hosts
with many cpus.

Even for moderate amount of netns processed by cleanup_net()
this patch avoids latency spikes.

[1] Some of these helpers like fib_sync_up() and fib_sync_down_dev()
are very slow because net/ipv4/fib_semantics.c uses host-wide hash tables,
and ifindex is used as the only input of two hash functions.
    ifindexes tend to be the same for all netns (lo.ifindex==1 per instance)
    This will be fixed in a separate patch.

Fixes: 72ad937abd0a ("net: Add support for batching network namespace cleanups")
Signed-off-by: Eric Dumazet 
Cc: Eric W. Biederman 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

inet: frags: annotate races around fqdir->dead and fqdir->high_thresh

2022-01-27T11:02:59+00:00

commit 91341fa0003befd097e190ec2a4bf63ad957c49a upstream.

Both fields can be read/written without synchronization,
add proper accessors and documentation.

Fixes: d5dd88794a13 ("inet: fix various use-after-free in defrags units")
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

mctp: test: zero out sockaddr

2022-01-27T11:02:58+00:00

commit 284a4d94e8e74fbd731ee67e29196656ca823423 upstream.

MCTP now requires that padding bytes are zero.

Signed-off-by: Matt Johnston 
Fixes: 1e4b50f06d97 ("mctp: handle the struct sockaddr_mctp padding fields")
Link: https://lore.kernel.org/r/20220110021806.2343023-1-matt@codeconstruct.com.au
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

net/smc: Fix hung_task when removing SMC-R devices

2022-01-27T11:02:57+00:00

commit 56d99e81ecbc997a5f984684d0eeb583992b2072 upstream.

A hung_task is observed when removing SMC-R devices. Suppose that
a link group has two active links(lnk_A, lnk_B) associated with two
different SMC-R devices(dev_A, dev_B). When dev_A is removed, the
link group will be removed from smc_lgr_list and added into
lgr_linkdown_list. lnk_A will be cleared and smcibdev(A)->lnk_cnt
will reach to zero. However, when dev_B is removed then, the link
group can't be found in smc_lgr_list and lnk_B won't be cleared,
making smcibdev->lnk_cnt never reaches zero, which causes a hung_task.

This patch fixes this issue by restoring the implementation of
smc_smcr_terminate_all() to what it was before commit 349d43127dac
("net/smc: fix kernel panic caused by race of smc_sock"). The original
implementation also satisfies the intention that make sure QP destroy
earlier than CQ destroy because we will always wait for smcibdev->lnk_cnt
reaches zero, which guarantees QP has been destroyed.

Fixes: 349d43127dac ("net/smc: fix kernel panic caused by race of smc_sock")
Signed-off-by: Wen Gu 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman