linux-stable.git/net/core, branch v5.0.9

net: core: netif_receive_skb_list: unlist skb before passing to pt->func

2019-04-17T06:39:43+00:00

[ Upstream commit 9a5a90d167b0e5fe3d47af16b68fd09ce64085cd ]

__netif_receive_skb_list_ptype() leaves skb->next poisoned before passing
it to pt_prev->func handler, what may produce (in certain cases, e.g. DSA
setup) crashes like:

[ 88.606777] CPU 0 Unable to handle kernel paging request at virtual address 0000000e, epc == 80687078, ra == 8052cc7c
[ 88.618666] Oops[#1]:
[ 88.621196] CPU: 0 PID: 0 Comm: swapper Not tainted 5.1.0-rc2-dlink-00206-g4192a172-dirty #1473
[ 88.630885] $ 0 : 00000000 10000400 00000002 864d7850
[ 88.636709] $ 4 : 87c0ddf0 864d7800 87c0ddf0 00000000
[ 88.642526] $ 8 : 00000000 49600000 00000001 00000001
[ 88.648342] $12 : 00000000 c288617b dadbee27 25d17c41
[ 88.654159] $16 : 87c0ddf0 85cff080 80790000 fffffffd
[ 88.659975] $20 : 80797b20 ffffffff 00000001 864d7800
[ 88.665793] $24 : 00000000 8011e658
[ 88.671609] $28 : 80790000 87c0dbc0 87cabf00 8052cc7c
[ 88.677427] Hi : 00000003
[ 88.680622] Lo : 7b5b4220
[ 88.683840] epc : 80687078 vlan_dev_hard_start_xmit+0x1c/0x1a0
[ 88.690532] ra : 8052cc7c dev_hard_start_xmit+0xac/0x188
[ 88.696734] Status: 10000404	IEp
[ 88.700422] Cause : 50000008 (ExcCode 02)
[ 88.704874] BadVA : 0000000e
[ 88.708069] PrId : 0001a120 (MIPS interAptiv (multi))
[ 88.713005] Modules linked in:
[ 88.716407] Process swapper (pid: 0, threadinfo=(ptrval), task=(ptrval), tls=00000000)
[ 88.725219] Stack : 85f61c28 00000000 0000000e 80780000 87c0ddf0 85cff080 80790000 8052cc7c
[ 88.734529] 87cabf00 00000000 00000001 85f5fb40 807b0000 864d7850 87cabf00 807d0000
[ 88.743839] 864d7800 8655f600 00000000 85cff080 87c1c000 0000006a 00000000 8052d96c
[ 88.753149] 807a0000 8057adb8 87c0dcc8 87c0dc50 85cfff08 00000558 87cabf00 85f58c50
[ 88.762460] 00000002 85f58c00 864d7800 80543308 fffffff4 00000001 85f58c00 864d7800
[ 88.771770] ...
[ 88.774483] Call Trace:
[ 88.777199] [<80687078>] vlan_dev_hard_start_xmit+0x1c/0x1a0
[ 88.783504] [<8052cc7c>] dev_hard_start_xmit+0xac/0x188
[ 88.789326] [<8052d96c>] __dev_queue_xmit+0x6e8/0x7d4
[ 88.794955] [<805a8640>] ip_finish_output2+0x238/0x4d0
[ 88.800677] [<805ab6a0>] ip_output+0xc8/0x140
[ 88.805526] [<805a68f4>] ip_forward+0x364/0x560
[ 88.810567] [<805a4ff8>] ip_rcv+0x48/0xe4
[ 88.815030] [<80528d44>] __netif_receive_skb_one_core+0x44/0x58
[ 88.821635] [<8067f220>] dsa_switch_rcv+0x108/0x1ac
[ 88.827067] [<80528f80>] __netif_receive_skb_list_core+0x228/0x26c
[ 88.833951] [<8052ed84>] netif_receive_skb_list+0x1d4/0x394
[ 88.840160] [<80355a88>] lunar_rx_poll+0x38c/0x828
[ 88.845496] [<8052fa78>] net_rx_action+0x14c/0x3cc
[ 88.850835] [<806ad300>] __do_softirq+0x178/0x338
[ 88.856077] [<8012a2d4>] irq_exit+0xbc/0x100
[ 88.860846] [<802f8b70>] plat_irq_dispatch+0xc0/0x144
[ 88.866477] [<80105974>] handle_int+0x14c/0x158
[ 88.871516] [<806acfb0>] r4k_wait+0x30/0x40
[ 88.876462] Code: afb10014 8c8200a0 00803025 <9443000c> 94a20468 00000000 10620042 00a08025 9605046a
[ 88.887332]
[ 88.888982] ---[ end trace eb863d007da11cf1 ]---
[ 88.894122] Kernel panic - not syncing: Fatal exception in interrupt
[ 88.901202] ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

Fix this by pulling skb off the sublist and zeroing skb->next pointer
before calling ptype callback.

Fixes: 88eb1944e18c ("net: core: propagate SKB lists through packet_type lookup")
Reviewed-by: Edward Cree 
Signed-off-by: Alexander Lobakin 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

netns: provide pure entropy for net_hash_mix()

2019-04-17T06:39:38+00:00

[ Upstream commit 355b98553789b646ed97ad801a619ff898471b92 ]

net_hash_mix() currently uses kernel address of a struct net,
and is used in many places that could be used to reveal this
address to a patient attacker, thus defeating KASLR, for
the typical case (initial net namespace, &init_net is
not dynamically allocated)

I believe the original implementation tried to avoid spending
too many cycles in this function, but security comes first.

Also provide entropy regardless of CONFIG_NET_NS.

Fixes: 0b4419162aa6 ("netns: introduce the net_hash_mix "salt" for hashes")
Signed-off-by: Eric Dumazet 
Reported-by: Amit Klein 
Reported-by: Benny Pinkas 
Cc: Pavel Emelyanov 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net-gro: Fix GRO flush when receiving a GSO packet.

2019-04-17T06:39:38+00:00

[ Upstream commit 0ab03f353d3613ea49d1f924faf98559003670a8 ]

Currently we may merge incorrectly a received GSO packet
or a packet with frag_list into a packet sitting in the
gro_hash list. skb_segment() may crash case because
the assumptions on the skb layout are not met.
The correct behaviour would be to flush the packet in the
gro_hash list and send the received GSO packet directly
afterwards. Commit d61d072e87c8e ("net-gro: avoid reorders")
sets NAPI_GRO_CB(skb)->flush in this case, but this is not
checked before merging. This patch makes sure to check this
flag and to not merge in that case.

Fixes: d61d072e87c8e ("net-gro: avoid reorders")
Signed-off-by: Steffen Klassert 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: ethtool: not call vzalloc for zero sized memory request

2019-04-17T06:39:37+00:00

[ Upstream commit 3d8830266ffc28c16032b859e38a0252e014b631 ]

NULL or ZERO_SIZE_PTR will be returned for zero sized memory
request, and derefencing them will lead to a segfault

so it is unnecessory to call vzalloc for zero sized memory
request and not call functions which maybe derefence the
NULL allocated memory

this also fixes a possible memory leak if phy_ethtool_get_stats
returns error, memory should be freed before exit

Signed-off-by: Li RongQing 
Reviewed-by: Wang Li 
Reviewed-by: Michal Kubecek 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net-sysfs: call dev_hold if kobject_init_and_add success

2019-04-03T04:27:24+00:00

[ Upstream commit a3e23f719f5c4a38ffb3d30c8d7632a4ed8ccd9e ]

In netdev_queue_add_kobject and rx_queue_add_kobject,
if sysfs_create_group failed, kobject_put will call
netdev_queue_release to decrease dev refcont, however
dev_hold has not be called. So we will see this while
unregistering dev:

unregister_netdevice: waiting for bcsh0 to become free. Usage count = -1

Reported-by: Hulk Robot 
Fixes: d0d668371679 ("net: don't decrement kobj reference count on init failure")
Signed-off-by: YueHaibing 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: datagram: fix unbounded loop in __skb_try_recv_datagram()

2019-04-03T04:27:23+00:00

[ Upstream commit 0b91bce1ebfc797ff3de60c8f4a1e6219a8a3187 ]

Christoph reported a stall while peeking datagram with an offset when
busy polling is enabled. __skb_try_recv_datagram() uses as the loop
termination condition 'queue empty'. When peeking, the socket
queue can be not empty, even when no additional packets are received.

Address the issue explicitly checking for receive queue changes,
as currently done by __skb_wait_for_more_packets().

Fixes: 2b5cd0dfa384 ("net: Change return type of sk_busy_loop from bool to void")
Reported-and-tested-by: Christoph Paasch 
Signed-off-by: Paolo Abeni 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

gro_cells: make sure device is up in gro_cells_receive()

2019-03-19T12:10:52+00:00

[ Upstream commit 2a5ff07a0eb945f291e361aa6f6becca8340ba46 ]

We keep receiving syzbot reports [1] that show that tunnels do not play
the rcu/IFF_UP rules properly.

At device dismantle phase, gro_cells_destroy() will be called
only after a full rcu grace period is observed after IFF_UP
has been cleared.

This means that IFF_UP needs to be tested before queueing packets
into netif_rx() or gro_cells.

This patch implements the test in gro_cells_receive() because
too many callers do not seem to bother enough.

[1]
BUG: unable to handle kernel paging request at fffff4ca0b9ffffe
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 21 Comm: kworker/u4:1 Not tainted 5.0.0+ #97
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
RIP: 0010:__skb_unlink include/linux/skbuff.h:1929 [inline]
RIP: 0010:__skb_dequeue include/linux/skbuff.h:1945 [inline]
RIP: 0010:__skb_queue_purge include/linux/skbuff.h:2656 [inline]
RIP: 0010:gro_cells_destroy net/core/gro_cells.c:89 [inline]
RIP: 0010:gro_cells_destroy+0x19d/0x360 net/core/gro_cells.c:78
Code: 03 42 80 3c 20 00 0f 85 53 01 00 00 48 8d 7a 08 49 8b 47 08 49 c7 07 00 00 00 00 48 89 f9 49 c7 47 08 00 00 00 00 48 c1 e9 03 <42> 80 3c 21 00 0f 85 10 01 00 00 48 89 c1 48 89 42 08 48 c1 e9 03
RSP: 0018:ffff8880aa3f79a8 EFLAGS: 00010a02
RAX: 00ffffffffffffe8 RBX: ffffe8ffffc64b70 RCX: 1ffff8ca0b9ffffe
RDX: ffffc6505cffffe8 RSI: ffffffff858410ca RDI: ffffc6505cfffff0
RBP: ffff8880aa3f7a08 R08: ffff8880aa3e8580 R09: fffffbfff1263645
R10: fffffbfff1263644 R11: ffffffff8931b223 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffe8ffffc64b80 R15: ffffe8ffffc64b75
kobject: 'loop2' (000000004bd7d84a): kobject_uevent_env
FS:  0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffff4ca0b9ffffe CR3: 0000000094941000 CR4: 00000000001406f0
Call Trace:
kobject: 'loop2' (000000004bd7d84a): fill_kobj_path: path = '/devices/virtual/block/loop2'
 ip_tunnel_dev_free+0x19/0x60 net/ipv4/ip_tunnel.c:1010
 netdev_run_todo+0x51c/0x7d0 net/core/dev.c:8970
 rtnl_unlock+0xe/0x10 net/core/rtnetlink.c:116
 ip_tunnel_delete_nets+0x423/0x5f0 net/ipv4/ip_tunnel.c:1124
 vti_exit_batch_net+0x23/0x30 net/ipv4/ip_vti.c:495
 ops_exit_list.isra.0+0x105/0x160 net/core/net_namespace.c:156
 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:551
 process_one_work+0x98e/0x1790 kernel/workqueue.c:2173
 worker_thread+0x98/0xe40 kernel/workqueue.c:2319
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Modules linked in:
CR2: fffff4ca0b9ffffe
   [ end trace 513fc9c1338d1cb3 ]
RIP: 0010:__skb_unlink include/linux/skbuff.h:1929 [inline]
RIP: 0010:__skb_dequeue include/linux/skbuff.h:1945 [inline]
RIP: 0010:__skb_queue_purge include/linux/skbuff.h:2656 [inline]
RIP: 0010:gro_cells_destroy net/core/gro_cells.c:89 [inline]
RIP: 0010:gro_cells_destroy+0x19d/0x360 net/core/gro_cells.c:78
Code: 03 42 80 3c 20 00 0f 85 53 01 00 00 48 8d 7a 08 49 8b 47 08 49 c7 07 00 00 00 00 48 89 f9 49 c7 47 08 00 00 00 00 48 c1 e9 03 <42> 80 3c 21 00 0f 85 10 01 00 00 48 89 c1 48 89 42 08 48 c1 e9 03
RSP: 0018:ffff8880aa3f79a8 EFLAGS: 00010a02
RAX: 00ffffffffffffe8 RBX: ffffe8ffffc64b70 RCX: 1ffff8ca0b9ffffe
RDX: ffffc6505cffffe8 RSI: ffffffff858410ca RDI: ffffc6505cfffff0
RBP: ffff8880aa3f7a08 R08: ffff8880aa3e8580 R09: fffffbfff1263645
R10: fffffbfff1263644 R11: ffffffff8931b223 R12: dffffc0000000000
kobject: 'loop3' (00000000e4ee57a6): kobject_uevent_env
R13: 0000000000000000 R14: ffffe8ffffc64b80 R15: ffffe8ffffc64b75
FS:  0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffff4ca0b9ffffe CR3: 0000000094941000 CR4: 00000000001406f0

Fixes: c9e6bc644e55 ("net: add gro_cells infrastructure")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bpf: Stop the psock parser before canceling its work

2019-03-13T21:01:31+00:00

commit e8e3437762ad938880dd48a3c52d702e7cf3c124 upstream.

We might have never enabled (started) the psock's parser, in which case it
will not get stopped when destroying the psock. This leads to a warning
when trying to cancel parser's work from psock's deferred destructor:

[  405.325769] WARNING: CPU: 1 PID: 3216 at net/strparser/strparser.c:526 strp_done+0x3c/0x40
[  405.326712] Modules linked in: [last unloaded: test_bpf]
[  405.327359] CPU: 1 PID: 3216 Comm: kworker/1:164 Tainted: G        W         5.0.0 #42
[  405.328294] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20180531_142017-buildhw-08.phx2.fedoraproject.org-1.fc28 04/01/2014
[  405.329712] Workqueue: events sk_psock_destroy_deferred
[  405.330254] RIP: 0010:strp_done+0x3c/0x40
[  405.330706] Code: 28 e8 b8 d5 6b ff 48 8d bb 80 00 00 00 e8 9c d5 6b ff 48 8b 7b 18 48 85 ff 74 0d e8 1e a5 e8 ff 48 c7 43 18 00 00 00 00 5b c3 <0f> 0b eb cf 66 66 66 66 90 55 89 f5 53 48 89 fb 48 83 c7 28 e8 0b
[  405.332862] RSP: 0018:ffffc900026bbe50 EFLAGS: 00010246
[  405.333482] RAX: ffffffff819323e0 RBX: ffff88812cb83640 RCX: ffff88812cb829e8
[  405.334228] RDX: 0000000000000001 RSI: ffff88812cb837e8 RDI: ffff88812cb83640
[  405.335366] RBP: ffff88813fd22680 R08: 0000000000000000 R09: 000073746e657665
[  405.336472] R10: 8080808080808080 R11: 0000000000000001 R12: ffff88812cb83600
[  405.337760] R13: 0000000000000000 R14: ffff88811f401780 R15: ffff88812cb837e8
[  405.338777] FS:  0000000000000000(0000) GS:ffff88813fd00000(0000) knlGS:0000000000000000
[  405.339903] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  405.340821] CR2: 00007fb11489a6b8 CR3: 000000012d4d6000 CR4: 00000000000406e0
[  405.341981] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  405.343131] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  405.344415] Call Trace:
[  405.344821]  sk_psock_destroy_deferred+0x23/0x1b0
[  405.345585]  process_one_work+0x1ae/0x3e0
[  405.346110]  worker_thread+0x3c/0x3b0
[  405.346576]  ? pwq_unbound_release_workfn+0xd0/0xd0
[  405.347187]  kthread+0x11d/0x140
[  405.347601]  ? __kthread_parkme+0x80/0x80
[  405.348108]  ret_from_fork+0x35/0x40
[  405.348566] ---[ end trace a4a3af4026a327d4 ]---

Stop psock's parser just before canceling its work.

Fixes: 1d79895aef18 ("sk_msg: Always cancel strp work before freeing the psock")
Reported-by: kernel test robot 
Signed-off-by: Jakub Sitnicki 
Signed-off-by: Daniel Borkmann 
Signed-off-by: Greg Kroah-Hartman

net-sysfs: Fix mem leak in netdev_register_kobject

2019-03-10T06:08:59+00:00

[ Upstream commit 895a5e96dbd6386c8e78e5b78e067dcc67b7f0ab ]

syzkaller report this:
BUG: memory leak
unreferenced object 0xffff88837a71a500 (size 256):
  comm "syz-executor.2", pid 9770, jiffies 4297825125 (age 17.843s)
  hex dump (first 32 bytes):
    00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00  .....N..........
    ff ff ff ff ff ff ff ff 20 c0 ef 86 ff ff ff ff  ........ .......
  backtrace:
    [<00000000db12624b>] netdev_register_kobject+0x124/0x2e0 net/core/net-sysfs.c:1751
    [<00000000dc49a994>] register_netdevice+0xcc1/0x1270 net/core/dev.c:8516
    [<00000000e5f3fea0>] tun_set_iff drivers/net/tun.c:2649 [inline]
    [<00000000e5f3fea0>] __tun_chr_ioctl+0x2218/0x3d20 drivers/net/tun.c:2883
    [<000000001b8ac127>] vfs_ioctl fs/ioctl.c:46 [inline]
    [<000000001b8ac127>] do_vfs_ioctl+0x1a5/0x10e0 fs/ioctl.c:690
    [<0000000079b269f8>] ksys_ioctl+0x89/0xa0 fs/ioctl.c:705
    [<00000000de649beb>] __do_sys_ioctl fs/ioctl.c:712 [inline]
    [<00000000de649beb>] __se_sys_ioctl fs/ioctl.c:710 [inline]
    [<00000000de649beb>] __x64_sys_ioctl+0x74/0xb0 fs/ioctl.c:710
    [<000000007ebded1e>] do_syscall_64+0xc8/0x580 arch/x86/entry/common.c:290
    [<00000000db315d36>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
    [<00000000115be9bb>] 0xffffffffffffffff

It should call kset_unregister to free 'dev->queues_kset'
in error path of register_queue_kobjects, otherwise will cause a mem leak.

Reported-by: Hulk Robot 
Fixes: 1d24eb4815d1 ("xps: Transmit Packet Steering")
Signed-off-by: YueHaibing 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: sched: put back q.qlen into a single location

2019-03-10T06:08:59+00:00

[ Upstream commit 46b1c18f9deb326a7e18348e668e4c7ab7c7458b ]

In the series fc8b81a5981f ("Merge branch 'lockless-qdisc-series'")
John made the assumption that the data path had no need to read
the qdisc qlen (number of packets in the qdisc).

It is true when pfifo_fast is used as the root qdisc, or as direct MQ/MQPRIO
children.

But pfifo_fast can be used as leaf in class full qdiscs, and existing
logic needs to access the child qlen in an efficient way.

HTB breaks badly, since it uses cl->leaf.q->q.qlen in :
  htb_activate() -> WARN_ON()
  htb_dequeue_tree() to decide if a class can be htb_deactivated
  when it has no more packets.

HFSC, DRR, CBQ, QFQ have similar issues, and some calls to
qdisc_tree_reduce_backlog() also read q.qlen directly.

Using qdisc_qlen_sum() (which iterates over all possible cpus)
in the data path is a non starter.

It seems we have to put back qlen in a central location,
at least for stable kernels.

For all qdisc but pfifo_fast, qlen is guarded by the qdisc lock,
so the existing q.qlen{++|--} are correct.

For 'lockless' qdisc (pfifo_fast so far), we need to use atomic_{inc|dec}()
because the spinlock might be not held (for example from
pfifo_fast_enqueue() and pfifo_fast_dequeue())

This patch adds atomic_qlen (in the same location than qlen)
and renames the following helpers, since we want to express
they can be used without qdisc lock, and that qlen is no longer percpu.

- qdisc_qstats_cpu_qlen_dec -> qdisc_qstats_atomic_qlen_dec()
- qdisc_qstats_cpu_qlen_inc -> qdisc_qstats_atomic_qlen_inc()

Later (net-next) we might revert this patch by tracking all these
qlen uses and replace them by a more efficient method (not having
to access a precise qlen, but an empty/non_empty status that might
be less expensive to maintain/track).

Another possibility is to have a legacy pfifo_fast version that would
be used when used a a child qdisc, since the parent qdisc needs
a spinlock anyway. But then, future lockless qdiscs would also
have the same problem.

Fixes: 7e66016f2c65 ("net: sched: helpers to sum qlen and qlen for per cpu logic")
Signed-off-by: Eric Dumazet 
Cc: John Fastabend 
Cc: Jamal Hadi Salim 
Cc: Cong Wang 
Cc: Jiri Pirko 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman