<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/git/stable/linux.git/net/sched, branch linux-5.19.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<id>https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/atom?h=linux-5.19.y</id>
<link rel='self' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/atom?h=linux-5.19.y'/>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/'/>
<updated>2022-10-05T08:40:51+00:00</updated>
<entry>
<title>net: sched: act_ct: fix possible refcount leak in tcf_ct_init()</title>
<updated>2022-10-05T08:40:51+00:00</updated>
<author>
<name>Hangyu Hua</name>
<email>hbh25y@gmail.com</email>
</author>
<published>2022-09-23T02:00:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3687a0c03863cdc3be085ca35f280abbb7f88df0'/>
<id>urn:sha1:3687a0c03863cdc3be085ca35f280abbb7f88df0</id>
<content type='text'>
[ Upstream commit 6e23ec0ba92d426c77a73a9ccab16346e5e0ef49 ]

nf_ct_put need to be called to put the refcount got by tcf_ct_fill_params
to avoid possible refcount leak when tcf_ct_flow_table_get fails.

Fixes: c34b961a2492 ("net/sched: act_ct: Create nf flow table per zone")
Signed-off-by: Hangyu Hua &lt;hbh25y@gmail.com&gt;
Link: https://lore.kernel.org/r/20220923020046.8021-1-hbh25y@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: sched: fix possible refcount leak in tc_new_tfilter()</title>
<updated>2022-09-28T09:32:21+00:00</updated>
<author>
<name>Hangyu Hua</name>
<email>hbh25y@gmail.com</email>
</author>
<published>2022-09-21T09:27:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=0559d91ee3a2cd81b15ad5cd507539d6da867f88'/>
<id>urn:sha1:0559d91ee3a2cd81b15ad5cd507539d6da867f88</id>
<content type='text'>
[ Upstream commit c2e1cfefcac35e0eea229e148c8284088ce437b5 ]

tfilter_put need to be called to put the refount got by tp-&gt;ops-&gt;get to
avoid possible refcount leak when chain-&gt;tmplt_ops != NULL and
chain-&gt;tmplt_ops != tp-&gt;ops.

Fixes: 7d5509fa0d3d ("net: sched: extend proto ops with 'put' callback")
Signed-off-by: Hangyu Hua &lt;hbh25y@gmail.com&gt;
Reviewed-by: Vlad Buslov &lt;vladbu@nvidia.com&gt;
Link: https://lore.kernel.org/r/20220921092734.31700-1-hbh25y@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net/sched: taprio: make qdisc_leaf() see the per-netdev-queue pfifo child qdiscs</title>
<updated>2022-09-28T09:32:18+00:00</updated>
<author>
<name>Vladimir Oltean</name>
<email>vladimir.oltean@nxp.com</email>
</author>
<published>2022-09-15T10:08:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=dff2fa3242078a76ea1e632e4df3e294bb57e82d'/>
<id>urn:sha1:dff2fa3242078a76ea1e632e4df3e294bb57e82d</id>
<content type='text'>
[ Upstream commit 1461d212ab277d8bba1a753d33e9afe03d81f9d4 ]

taprio can only operate as root qdisc, and to that end, there exists the
following check in taprio_init(), just as in mqprio:

	if (sch-&gt;parent != TC_H_ROOT)
		return -EOPNOTSUPP;

And indeed, when we try to attach taprio to an mqprio child, it fails as
expected:

$ tc qdisc add dev swp0 root handle 1: mqprio num_tc 8 \
	map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 0
$ tc qdisc replace dev swp0 parent 1:2 taprio num_tc 8 \
	map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \
	base-time 0 sched-entry S 0x7f 990000 sched-entry S 0x80 100000 \
	flags 0x0 clockid CLOCK_TAI
Error: sch_taprio: Can only be attached as root qdisc.

(extack message added by me)

But when we try to attach a taprio child to a taprio root qdisc,
surprisingly it doesn't fail:

$ tc qdisc replace dev swp0 root handle 1: taprio num_tc 8 \
	map 0 1 2 3 4 5 6 7 queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \
	base-time 0 sched-entry S 0x7f 990000 sched-entry S 0x80 100000 \
	flags 0x0 clockid CLOCK_TAI
$ tc qdisc replace dev swp0 parent 1:2 taprio num_tc 8 \
	map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \
	base-time 0 sched-entry S 0x7f 990000 sched-entry S 0x80 100000 \
	flags 0x0 clockid CLOCK_TAI

This is because tc_modify_qdisc() behaves differently when mqprio is
root, vs when taprio is root.

In the mqprio case, it finds the parent qdisc through
p = qdisc_lookup(dev, TC_H_MAJ(clid)), and then the child qdisc through
q = qdisc_leaf(p, clid). This leaf qdisc q has handle 0, so it is
ignored according to the comment right below ("It may be default qdisc,
ignore it"). As a result, tc_modify_qdisc() goes through the
qdisc_create() code path, and this gives taprio_init() a chance to check
for sch_parent != TC_H_ROOT and error out.

Whereas in the taprio case, the returned q = qdisc_leaf(p, clid) is
different. It is not the default qdisc created for each netdev queue
(both taprio and mqprio call qdisc_create_dflt() and keep them in
a private q-&gt;qdiscs[], or priv-&gt;qdiscs[], respectively). Instead, taprio
makes qdisc_leaf() return the _root_ qdisc, aka itself.

When taprio does that, tc_modify_qdisc() goes through the qdisc_change()
code path, because the qdisc layer never finds out about the child qdisc
of the root. And through the -&gt;change() ops, taprio has no reason to
check whether its parent is root or not, just through -&gt;init(), which is
not called.

The problem is the taprio_leaf() implementation. Even though code wise,
it does the exact same thing as mqprio_leaf() which it is copied from,
it works with different input data. This is because mqprio does not
attach itself (the root) to each device TX queue, but one of the default
qdiscs from its private array.

In fact, since commit 13511704f8d7 ("net: taprio offload: enforce qdisc
to netdev queue mapping"), taprio does this too, but just for the full
offload case. So if we tried to attach a taprio child to a fully
offloaded taprio root qdisc, it would properly fail too; just not to a
software root taprio.

To fix the problem, stop looking at the Qdisc that's attached to the TX
queue, and instead, always return the default qdiscs that we've
allocated (and to which we privately enqueue and dequeue, in software
scheduling mode).

Since Qdisc_class_ops :: leaf  is only called from tc_modify_qdisc(),
the risk of unforeseen side effects introduced by this change is
minimal.

Fixes: 5a781ccbd19e ("tc: Add support for configuring the taprio scheduler")
Signed-off-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Reviewed-by: Vinicius Costa Gomes &lt;vinicius.gomes@intel.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net/sched: taprio: avoid disabling offload when it was never enabled</title>
<updated>2022-09-28T09:32:17+00:00</updated>
<author>
<name>Vladimir Oltean</name>
<email>vladimir.oltean@nxp.com</email>
</author>
<published>2022-09-15T10:08:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c7c9c7eb305ab8b4e93e4e4e1b78d8cfcbc26323'/>
<id>urn:sha1:c7c9c7eb305ab8b4e93e4e4e1b78d8cfcbc26323</id>
<content type='text'>
[ Upstream commit db46e3a88a09c5cf7e505664d01da7238cd56c92 ]

In an incredibly strange API design decision, qdisc-&gt;destroy() gets
called even if qdisc-&gt;init() never succeeded, not exclusively since
commit 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation"),
but apparently also earlier (in the case of qdisc_create_dflt()).

The taprio qdisc does not fully acknowledge this when it attempts full
offload, because it starts off with q-&gt;flags = TAPRIO_FLAGS_INVALID in
taprio_init(), then it replaces q-&gt;flags with TCA_TAPRIO_ATTR_FLAGS
parsed from netlink (in taprio_change(), tail called from taprio_init()).

But in taprio_destroy(), we call taprio_disable_offload(), and this
determines what to do based on FULL_OFFLOAD_IS_ENABLED(q-&gt;flags).

But looking at the implementation of FULL_OFFLOAD_IS_ENABLED()
(a bitwise check of bit 1 in q-&gt;flags), it is invalid to call this macro
on q-&gt;flags when it contains TAPRIO_FLAGS_INVALID, because that is set
to U32_MAX, and therefore FULL_OFFLOAD_IS_ENABLED() will return true on
an invalid set of flags.

As a result, it is possible to crash the kernel if user space forces an
error between setting q-&gt;flags = TAPRIO_FLAGS_INVALID, and the calling
of taprio_enable_offload(). This is because drivers do not expect the
offload to be disabled when it was never enabled.

The error that we force here is to attach taprio as a non-root qdisc,
but instead as child of an mqprio root qdisc:

$ tc qdisc add dev swp0 root handle 1: \
	mqprio num_tc 8 map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 0
$ tc qdisc replace dev swp0 parent 1:1 \
	taprio num_tc 8 map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 base-time 0 \
	sched-entry S 0x7f 990000 sched-entry S 0x80 100000 \
	flags 0x0 clockid CLOCK_TAI
Unable to handle kernel paging request at virtual address fffffffffffffff8
[fffffffffffffff8] pgd=0000000000000000, p4d=0000000000000000
Internal error: Oops: 96000004 [#1] PREEMPT SMP
Call trace:
 taprio_dump+0x27c/0x310
 vsc9959_port_setup_tc+0x1f4/0x460
 felix_port_setup_tc+0x24/0x3c
 dsa_slave_setup_tc+0x54/0x27c
 taprio_disable_offload.isra.0+0x58/0xe0
 taprio_destroy+0x80/0x104
 qdisc_create+0x240/0x470
 tc_modify_qdisc+0x1fc/0x6b0
 rtnetlink_rcv_msg+0x12c/0x390
 netlink_rcv_skb+0x5c/0x130
 rtnetlink_rcv+0x1c/0x2c

Fix this by keeping track of the operations we made, and undo the
offload only if we actually did it.

I've added "bool offloaded" inside a 4 byte hole between "int clockid"
and "atomic64_t picos_per_byte". Now the first cache line looks like
below:

$ pahole -C taprio_sched net/sched/sch_taprio.o
struct taprio_sched {
        struct Qdisc * *           qdiscs;               /*     0     8 */
        struct Qdisc *             root;                 /*     8     8 */
        u32                        flags;                /*    16     4 */
        enum tk_offsets            tk_offset;            /*    20     4 */
        int                        clockid;              /*    24     4 */
        bool                       offloaded;            /*    28     1 */

        /* XXX 3 bytes hole, try to pack */

        atomic64_t                 picos_per_byte;       /*    32     0 */

        /* XXX 8 bytes hole, try to pack */

        spinlock_t                 current_entry_lock;   /*    40     0 */

        /* XXX 8 bytes hole, try to pack */

        struct sched_entry *       current_entry;        /*    48     8 */
        struct sched_gate_list *   oper_sched;           /*    56     8 */
        /* --- cacheline 1 boundary (64 bytes) --- */

Fixes: 9c66d1564676 ("taprio: Add support for hardware offloading")
Signed-off-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Reviewed-by: Vinicius Costa Gomes &lt;vinicius.gomes@intel.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>time64.h: consolidate uses of PSEC_PER_NSEC</title>
<updated>2022-09-15T08:47:19+00:00</updated>
<author>
<name>Vladimir Oltean</name>
<email>vladimir.oltean@nxp.com</email>
</author>
<published>2022-06-28T14:52:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c078abef701da227175cf3de0f07abddb0d3b351'/>
<id>urn:sha1:c078abef701da227175cf3de0f07abddb0d3b351</id>
<content type='text'>
[ Upstream commit 837ced3a1a5d8bb1a637dd584711f31ae6b54d93 ]

Time-sensitive networking code needs to work with PTP times expressed in
nanoseconds, and with packet transmission times expressed in
picoseconds, since those would be fractional at higher than gigabit
speed when expressed in nanoseconds.

Convert the existing uses in tc-taprio and the ocelot/felix DSA driver
to a PSEC_PER_NSEC macro. This macro is placed in include/linux/time64.h
as opposed to its relatives (PSEC_PER_SEC etc) from include/vdso/time64.h
because the vDSO library does not (yet) need/use it.

Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Reviewed-by: Vincenzo Frascino &lt;vincenzo.frascino@arm.com&gt; # for the vDSO parts
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Stable-dep-of: 11afdc6526de ("net: dsa: felix: tc-taprio intervals smaller than MTU should send at least one packet")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>sch_sfb: Also store skb len before calling child enqueue</title>
<updated>2022-09-15T08:47:17+00:00</updated>
<author>
<name>Toke Høiland-Jørgensen</name>
<email>toke@toke.dk</email>
</author>
<published>2022-09-05T19:21:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5ec0821b85ff0097ea5e582c03f65c6014ca2807'/>
<id>urn:sha1:5ec0821b85ff0097ea5e582c03f65c6014ca2807</id>
<content type='text'>
[ Upstream commit 2f09707d0c972120bf794cfe0f0c67e2c2ddb252 ]

Cong Wang noticed that the previous fix for sch_sfb accessing the queued
skb after enqueueing it to a child qdisc was incomplete: the SFB enqueue
function was also calling qdisc_qstats_backlog_inc() after enqueue, which
reads the pkt len from the skb cb field. Fix this by also storing the skb
len, and using the stored value to increment the backlog after enqueueing.

Fixes: 9efd23297cca ("sch_sfb: Don't assume the skb is still around after enqueueing to child")
Signed-off-by: Toke Høiland-Jørgensen &lt;toke@toke.dk&gt;
Acked-by: Cong Wang &lt;cong.wang@bytedance.com&gt;
Link: https://lore.kernel.org/r/20220905192137.965549-1-toke@toke.dk
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>sch_sfb: Don't assume the skb is still around after enqueueing to child</title>
<updated>2022-09-15T08:47:15+00:00</updated>
<author>
<name>Toke Høiland-Jørgensen</name>
<email>toke@toke.dk</email>
</author>
<published>2022-08-31T21:52:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=8f796f36f5ba839c11eb4685150ebeed496c546f'/>
<id>urn:sha1:8f796f36f5ba839c11eb4685150ebeed496c546f</id>
<content type='text'>
[ Upstream commit 9efd23297cca530bb35e1848665805d3fcdd7889 ]

The sch_sfb enqueue() routine assumes the skb is still alive after it has
been enqueued into a child qdisc, using the data in the skb cb field in the
increment_qlen() routine after enqueue. However, the skb may in fact have
been freed, causing a use-after-free in this case. In particular, this
happens if sch_cake is used as a child of sfb, and the GSO splitting mode
of CAKE is enabled (in which case the skb will be split into segments and
the original skb freed).

Fix this by copying the sfb cb data to the stack before enqueueing the skb,
and using this stack copy in increment_qlen() instead of the skb pointer
itself.

Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-18231
Fixes: e13e02a3c68d ("net_sched: SFB flow scheduler")
Signed-off-by: Toke Høiland-Jørgensen &lt;toke@toke.dk&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>Revert "sch_cake: Return __NET_XMIT_STOLEN when consuming enqueued skb"</title>
<updated>2022-09-08T09:24:00+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2022-09-01T03:01:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1e789ee9b07456bbee663040ddad504ebc3957e3'/>
<id>urn:sha1:1e789ee9b07456bbee663040ddad504ebc3957e3</id>
<content type='text'>
[ Upstream commit 0b4f688d53fdc2a731b9d9cdf0c96255bc024ea6 ]

This reverts commit 90fabae8a2c225c4e4936723c38857887edde5cc.

Patch was applied hastily, revert and let the v2 be reviewed.

Fixes: 90fabae8a2c2 ("sch_cake: Return __NET_XMIT_STOLEN when consuming enqueued skb")
Link: https://lore.kernel.org/all/87wnao2ha3.fsf@toke.dk/
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>sch_cake: Return __NET_XMIT_STOLEN when consuming enqueued skb</title>
<updated>2022-09-08T09:24:00+00:00</updated>
<author>
<name>Toke Høiland-Jørgensen</name>
<email>toke@toke.dk</email>
</author>
<published>2022-08-31T09:21:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=ca94a50666767a1186f783ac515a5e11c883c386'/>
<id>urn:sha1:ca94a50666767a1186f783ac515a5e11c883c386</id>
<content type='text'>
[ Upstream commit 90fabae8a2c225c4e4936723c38857887edde5cc ]

When the GSO splitting feature of sch_cake is enabled, GSO superpackets
will be broken up and the resulting segments enqueued in place of the
original skb. In this case, CAKE calls consume_skb() on the original skb,
but still returns NET_XMIT_SUCCESS. This can confuse parent qdiscs into
assuming the original skb still exists, when it really has been freed. Fix
this by adding the __NET_XMIT_STOLEN flag to the return value in this case.

Fixes: 0c850344d388 ("sch_cake: Conditionally split GSO segments")
Signed-off-by: Toke Høiland-Jørgensen &lt;toke@toke.dk&gt;
Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-18231
Link: https://lore.kernel.org/r/20220831092103.442868-1-toke@toke.dk
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net/sched: fix netdevice reference leaks in attach_default_qdiscs()</title>
<updated>2022-09-08T09:23:59+00:00</updated>
<author>
<name>Wang Hai</name>
<email>wanghai38@huawei.com</email>
</author>
<published>2022-08-26T09:00:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=0c6c522857151ac00150fd01baeebf231fb7d142'/>
<id>urn:sha1:0c6c522857151ac00150fd01baeebf231fb7d142</id>
<content type='text'>
[ Upstream commit f612466ebecb12a00d9152344ddda6f6345f04dc ]

In attach_default_qdiscs(), if a dev has multiple queues and queue 0 fails
to attach qdisc because there is no memory in attach_one_default_qdisc().
Then dev-&gt;qdisc will be noop_qdisc by default. But the other queues may be
able to successfully attach to default qdisc.

In this case, the fallback to noqueue process will be triggered. If the
original attached qdisc is not released and a new one is directly
attached, this will cause netdevice reference leaks.

The following is the bug log:

veth0: default qdisc (fq_codel) fail, fallback to noqueue
unregister_netdevice: waiting for veth0 to become free. Usage count = 32
leaked reference.
 qdisc_alloc+0x12e/0x210
 qdisc_create_dflt+0x62/0x140
 attach_one_default_qdisc.constprop.41+0x44/0x70
 dev_activate+0x128/0x290
 __dev_open+0x12a/0x190
 __dev_change_flags+0x1a2/0x1f0
 dev_change_flags+0x23/0x60
 do_setlink+0x332/0x1150
 __rtnl_newlink+0x52f/0x8e0
 rtnl_newlink+0x43/0x70
 rtnetlink_rcv_msg+0x140/0x3b0
 netlink_rcv_skb+0x50/0x100
 netlink_unicast+0x1bb/0x290
 netlink_sendmsg+0x37c/0x4e0
 sock_sendmsg+0x5f/0x70
 ____sys_sendmsg+0x208/0x280

Fix this bug by clearing any non-noop qdiscs that may have been assigned
before trying to re-attach.

Fixes: bf6dba76d278 ("net: sched: fallback to qdisc noqueue if default qdisc setup fail")
Signed-off-by: Wang Hai &lt;wanghai38@huawei.com&gt;
Link: https://lore.kernel.org/r/20220826090055.24424-1-wanghai38@huawei.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
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