linux.git/net/sched, branch v4.19.145

sched: consistently handle layer3 header accesses in the presence of VLANs

2020-07-22T07:32:00+00:00

[ Upstream commit d7bf2ebebc2bd61ab95e2a8e33541ef282f303d4 ]

There are a couple of places in net/sched/ that check skb->protocol and act
on the value there. However, in the presence of VLAN tags, the value stored
in skb->protocol can be inconsistent based on whether VLAN acceleration is
enabled. The commit quoted in the Fixes tag below fixed the users of
skb->protocol to use a helper that will always see the VLAN ethertype.

However, most of the callers don't actually handle the VLAN ethertype, but
expect to find the IP header type in the protocol field. This means that
things like changing the ECN field, or parsing diffserv values, stops
working if there's a VLAN tag, or if there are multiple nested VLAN
tags (QinQ).

To fix this, change the helper to take an argument that indicates whether
the caller wants to skip the VLAN tags or not. When skipping VLAN tags, we
make sure to skip all of them, so behaviour is consistent even in QinQ
mode.

To make the helper usable from the ECN code, move it to if_vlan.h instead
of pkt_sched.h.

v3:
- Remove empty lines
- Move vlan variable definitions inside loop in skb_protocol()
- Also use skb_protocol() helper in IP{,6}_ECN_decapsulate() and
  bpf_skb_ecn_set_ce()

v2:
- Use eth_type_vlan() helper in skb_protocol()
- Also fix code that reads skb->protocol directly
- Change a couple of 'if/else if' statements to switch constructs to avoid
  calling the helper twice

Reported-by: Ilya Ponetayev 
Fixes: d8b9605d2697 ("net: sched: fix skb->protocol use in case of accelerated vlan path")
Signed-off-by: Toke Høiland-Jørgensen 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net_sched: fix a memory leak in atm_tc_init()

2020-07-22T07:31:59+00:00

[ Upstream commit 306381aec7c2b5a658eebca008c8a1b666536cba ]

When tcf_block_get() fails inside atm_tc_init(),
atm_tc_put() is called to release the qdisc p->link.q.
But the flow->ref prevents it to do so, as the flow->ref
is still zero.

Fix this by moving the p->link.ref initialization before
tcf_block_get().

Fixes: 6529eaba33f0 ("net: sched: introduce tcf block infractructure")
Reported-and-tested-by: syzbot+d411cff6ab29cc2c311b@syzkaller.appspotmail.com
Cc: Jamal Hadi Salim 
Cc: Jiri Pirko 
Signed-off-by: Cong Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sch_cake: don't call diffserv parsing code when it is not needed

2020-07-01T03:17:06+00:00

[ Upstream commit 8c95eca0bb8c4bd2231a0d581f1ad0d50c90488c ]

As a further optimisation of the diffserv parsing codepath, we can skip it
entirely if CAKE is configured to neither use diffserv-based
classification, nor to zero out the diffserv bits.

Fixes: c87b4ecdbe8d ("sch_cake: Make sure we can write the IP header before changing DSCP bits")
Signed-off-by: Toke Høiland-Jørgensen 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sch_cake: fix a few style nits

2020-07-01T03:17:06+00:00

[ Upstream commit 3f608f0c41360b11b04c763f348b712f651c8bac ]

I spotted a few nits when comparing the in-tree version of sch_cake with
the out-of-tree one: A redundant error variable declaration shadowing an
outer declaration, and an indentation alignment issue. Fix both of these.

Fixes: 046f6fd5daef ("sched: Add Common Applications Kept Enhanced (cake) qdisc")
Signed-off-by: Toke Høiland-Jørgensen 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sch_cake: don't try to reallocate or unshare skb unconditionally

2020-07-01T03:17:06+00:00

[ Upstream commit 9208d2863ac689a563b92f2161d8d1e7127d0add ]

cake_handle_diffserv() tries to linearize mac and network header parts of
skb and to make it writable unconditionally. In some cases it leads to full
skb reallocation, which reduces throughput and increases CPU load. Some
measurements of IPv4 forward + NAPT on MIPS router with 580 MHz single-core
CPU was conducted. It appears that on kernel 4.9 skb_try_make_writable()
reallocates skb, if skb was allocated in ethernet driver via so-called
'build skb' method from page cache (it was discovered by strange increase
of kmalloc-2048 slab at first).

Obtain DSCP value via read-only skb_header_pointer() call, and leave
linearization only for DSCP bleaching or ECN CE setting. And, as an
additional optimisation, skip diffserv parsing entirely if it is not needed
by the current configuration.

Fixes: c87b4ecdbe8d ("sch_cake: Make sure we can write the IP header before changing DSCP bits")
Signed-off-by: Ilya Ponetayev 
[ fix a few style issues, reflow commit message ]
Signed-off-by: Toke Høiland-Jørgensen 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: sched: export __netdev_watchdog_up()

2020-07-01T03:17:01+00:00

[ Upstream commit 1a3db27ad9a72d033235b9673653962c02e3486e ]

Since the quiesce/activate rework, __netdev_watchdog_up() is directly
called in the ucc_geth driver.

Unfortunately, this function is not available for modules and thus
ucc_geth cannot be built as a module anymore. Fix it by exporting
__netdev_watchdog_up().

Since the commit introducing the regression was backported to stable
branches, this one should ideally be as well.

Fixes: 79dde73cf9bc ("net/ethernet/freescale: rework quiesce/activate for ucc_geth")
Signed-off-by: Valentin Longchamp 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

sch_sfq: validate silly quantum values

2020-05-14T05:57:18+00:00

[ Upstream commit df4953e4e997e273501339f607b77953772e3559 ]

syzbot managed to set up sfq so that q->scaled_quantum was zero,
triggering an infinite loop in sfq_dequeue()

More generally, we must only accept quantum between 1 and 2^18 - 7,
meaning scaled_quantum must be in [1, 0x7FFF] range.

Otherwise, we also could have a loop in sfq_dequeue()
if scaled_quantum happens to be 0x8000, since slot->allot
could indefinitely switch between 0 and 0x8000.

Fixes: eeaeb068f139 ("sch_sfq: allow big packets and be fair")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot+0251e883fe39e7a0cb0a@syzkaller.appspotmail.com
Cc: Jason A. Donenfeld 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sch_choke: avoid potential panic in choke_reset()

2020-05-14T05:57:18+00:00

[ Upstream commit 8738c85c72b3108c9b9a369a39868ba5f8e10ae0 ]

If choke_init() could not allocate q->tab, we would crash later
in choke_reset().

BUG: KASAN: null-ptr-deref in memset include/linux/string.h:366 [inline]
BUG: KASAN: null-ptr-deref in choke_reset+0x208/0x340 net/sched/sch_choke.c:326
Write of size 8 at addr 0000000000000000 by task syz-executor822/7022

CPU: 1 PID: 7022 Comm: syz-executor822 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 __kasan_report.cold+0x5/0x4d mm/kasan/report.c:515
 kasan_report+0x33/0x50 mm/kasan/common.c:625
 check_memory_region_inline mm/kasan/generic.c:187 [inline]
 check_memory_region+0x141/0x190 mm/kasan/generic.c:193
 memset+0x20/0x40 mm/kasan/common.c:85
 memset include/linux/string.h:366 [inline]
 choke_reset+0x208/0x340 net/sched/sch_choke.c:326
 qdisc_reset+0x6b/0x520 net/sched/sch_generic.c:910
 dev_deactivate_queue.constprop.0+0x13c/0x240 net/sched/sch_generic.c:1138
 netdev_for_each_tx_queue include/linux/netdevice.h:2197 [inline]
 dev_deactivate_many+0xe2/0xba0 net/sched/sch_generic.c:1195
 dev_deactivate+0xf8/0x1c0 net/sched/sch_generic.c:1233
 qdisc_graft+0xd25/0x1120 net/sched/sch_api.c:1051
 tc_modify_qdisc+0xbab/0x1a00 net/sched/sch_api.c:1670
 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5454
 netlink_rcv_skb+0x15a/0x410 net/netlink/af_netlink.c:2469
 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
 netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329
 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 ____sys_sendmsg+0x6bf/0x7e0 net/socket.c:2362
 ___sys_sendmsg+0x100/0x170 net/socket.c:2416
 __sys_sendmsg+0xec/0x1b0 net/socket.c:2449
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295

Fixes: 77e62da6e60c ("sch_choke: drop all packets in queue during reset")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Cc: Cong Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net_sched: sch_skbprio: add message validation to skbprio_change()

2020-05-14T05:57:17+00:00

[ Upstream commit 2761121af87de45951989a0adada917837d8fa82 ]

Do not assume the attribute has the right size.

Fixes: aea5f654e6b7 ("net/sched: add skbprio scheduler")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

fq_codel: fix TCA_FQ_CODEL_DROP_BATCH_SIZE sanity checks

2020-05-14T05:57:17+00:00

[ Upstream commit 14695212d4cd8b0c997f6121b6df8520038ce076 ]

My intent was to not let users set a zero drop_batch_size,
it seems I once again messed with min()/max().

Fixes: 9d18562a2278 ("fq_codel: add batch ability to fq_codel_drop()")
Signed-off-by: Eric Dumazet 
Acked-by: Toke Høiland-Jørgensen 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman