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net/compat: Add missing sock updates for SCM_RIGHTS
commit d9539752d23283db4692384a634034f451261e29 upstream.

Add missed sock updates to compat path via a new helper, which will be
used more in coming patches. (The net/core/scm.c code is left as-is here
to assist with -stable backports for the compat path.)

Cc: Christoph Hellwig <hch@lst.de>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 48a87cc26c ("net: netprio: fd passed in SCM_RIGHTS datagram not set correctly")
Fixes: d84295067f ("net: net_cls: fd passed in SCM_RIGHTS datagram not set correctly")
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Kees Cook   authored and   Greg Kroah-Hartman   commited 2020-08-21 11:05:32 +02:00
f90339a4ec
rtnetlink: Fix memory(net_device) leak when ->newlink fails
[ Upstream commit cebb69754f37d68e1355a5e726fdac317bcda302 ]

When vlan_newlink call register_vlan_dev fails, it might return error
with dev->reg_state = NETREG_UNREGISTERED. The rtnl_newlink should
free the memory. But currently rtnl_newlink only free the memory which
state is NETREG_UNINITIALIZED.

BUG: memory leak
unreferenced object 0xffff8881051de000 (size 4096):
  comm "syz-executor139", pid 560, jiffies 4294745346 (age 32.445s)
  hex dump (first 32 bytes):
    76 6c 61 6e 32 00 00 00 00 00 00 00 00 00 00 00  vlan2...........
    00 45 28 03 81 88 ff ff 00 00 00 00 00 00 00 00  .E(.............
  backtrace:
    [<0000000047527e31>] kmalloc_node include/linux/slab.h:578 [inline]
    [<0000000047527e31>] kvmalloc_node+0x33/0xd0 mm/util.c:574
    [<000000002b59e3bc>] kvmalloc include/linux/mm.h:753 [inline]
    [<000000002b59e3bc>] kvzalloc include/linux/mm.h:761 [inline]
    [<000000002b59e3bc>] alloc_netdev_mqs+0x83/0xd90 net/core/dev.c:9929
    [<000000006076752a>] rtnl_create_link+0x2c0/0xa20 net/core/rtnetlink.c:3067
    [<00000000572b3be5>] __rtnl_newlink+0xc9c/0x1330 net/core/rtnetlink.c:3329
    [<00000000e84ea553>] rtnl_newlink+0x66/0x90 net/core/rtnetlink.c:3397
    [<0000000052c7c0a9>] rtnetlink_rcv_msg+0x540/0x990 net/core/rtnetlink.c:5460
    [<000000004b5cb379>] netlink_rcv_skb+0x12b/0x3a0 net/netlink/af_netlink.c:2469
    [<00000000c71c20d3>] netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
    [<00000000c71c20d3>] netlink_unicast+0x4c6/0x690 net/netlink/af_netlink.c:1329
    [<00000000cca72fa9>] netlink_sendmsg+0x735/0xcc0 net/netlink/af_netlink.c:1918
    [<000000009221ebf7>] sock_sendmsg_nosec net/socket.c:652 [inline]
    [<000000009221ebf7>] sock_sendmsg+0x109/0x140 net/socket.c:672
    [<000000001c30ffe4>] ____sys_sendmsg+0x5f5/0x780 net/socket.c:2352
    [<00000000b71ca6f3>] ___sys_sendmsg+0x11d/0x1a0 net/socket.c:2406
    [<0000000007297384>] __sys_sendmsg+0xeb/0x1b0 net/socket.c:2439
    [<000000000eb29b11>] do_syscall_64+0x56/0xa0 arch/x86/entry/common.c:359
    [<000000006839b4d0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: cb626bf566eb ("net-sysfs: Fix reference count leak")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Weilong Chen <chenweilong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Weilong Chen   authored and   Greg Kroah-Hartman   commited 2020-07-31 18:37:49 +02:00
ddb5bba463
udp: Copy has_conns in reuseport_grow().
[ Upstream commit f2b2c55e512879a05456eaf5de4d1ed2f7757509 ]

If an unconnected socket in a UDP reuseport group connect()s, has_conns is
set to 1. Then, when a packet is received, udp[46]_lib_lookup2() scans all
sockets in udp_hslot looking for the connected socket with the highest
score.

However, when the number of sockets bound to the port exceeds max_socks,
reuseport_grow() resets has_conns to 0. It can cause udp[46]_lib_lookup2()
to return without scanning all sockets, resulting in that packets sent to
connected sockets may be distributed to unconnected sockets.

Therefore, reuseport_grow() should copy has_conns.

Fixes: acdcecc61285 ("udp: correct reuseport selection with connected sockets")
CC: Willem de Bruijn <willemb@google.com>
Reviewed-by: Benjamin Herrenschmidt <benh@amazon.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Kuniyuki Iwashima   authored and   Greg Kroah-Hartman   commited 2020-07-31 18:37:48 +02:00
0f26f9672b
net-sysfs: add a newline when printing 'tx_timeout' by sysfs
[ Upstream commit 9bb5fbea59f36a589ef886292549ca4052fe676c ]

When I cat 'tx_timeout' by sysfs, it displays as follows. It's better to
add a newline for easy reading.

root@syzkaller:~# cat /sys/devices/virtual/net/lo/queues/tx-0/tx_timeout
0root@syzkaller:~#

Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Xiongfeng Wang   authored and   Greg Kroah-Hartman   commited 2020-07-31 18:37:47 +02:00
ea19403632
dev: Defer free of skbs in flush_backlog
[ Upstream commit 7df5cb75cfb8acf96c7f2342530eb41e0c11f4c3 ]

IRQs are disabled when freeing skbs in input queue.
Use the IRQ safe variant to free skbs here.

Fixes: 145dd5f9c8 ("net: flush the softnet backlog in process context")
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Subash Abhinov Kasiviswanathan   authored and   Greg Kroah-Hartman   commited 2020-07-31 18:37:47 +02:00
68c46a0adc
sched: consistently handle layer3 header accesses in the presence of VLANs
[ 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 <i.ponetaev@ndmsystems.com>
Fixes: d8b9605d26 ("net: sched: fix skb->protocol use in case of accelerated vlan path")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Toke Høiland-Jørgensen   authored and   Greg Kroah-Hartman   commited 2020-07-22 09:32:00 +02:00
9fd235ff00
cgroup: fix cgroup_sk_alloc() for sk_clone_lock()
[ Upstream commit ad0f75e5f57ccbceec13274e1e242f2b5a6397ed ]

When we clone a socket in sk_clone_lock(), its sk_cgrp_data is
copied, so the cgroup refcnt must be taken too. And, unlike the
sk_alloc() path, sock_update_netprioidx() is not called here.
Therefore, it is safe and necessary to grab the cgroup refcnt
even when cgroup_sk_alloc is disabled.

sk_clone_lock() is in BH context anyway, the in_interrupt()
would terminate this function if called there. And for sk_alloc()
skcd->val is always zero. So it's safe to factor out the code
to make it more readable.

The global variable 'cgroup_sk_alloc_disabled' is used to determine
whether to take these reference counts. It is impossible to make
the reference counting correct unless we save this bit of information
in skcd->val. So, add a new bit there to record whether the socket
has already taken the reference counts. This obviously relies on
kmalloc() to align cgroup pointers to at least 4 bytes,
ARCH_KMALLOC_MINALIGN is certainly larger than that.

This bug seems to be introduced since the beginning, commit
d979a39d72 ("cgroup: duplicate cgroup reference when cloning sockets")
tried to fix it but not compeletely. It seems not easy to trigger until
the recent commit 090e28b229af
("netprio_cgroup: Fix unlimited memory leak of v2 cgroups") was merged.

Fixes: bd1060a1d6 ("sock, cgroup: add sock->sk_cgroup")
Reported-by: Cameron Berkenpas <cam@neo-zeon.de>
Reported-by: Peter Geis <pgwipeout@gmail.com>
Reported-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reported-by: Daniël Sonck <dsonck92@gmail.com>
Reported-by: Zhang Qiang <qiang.zhang@windriver.com>
Tested-by: Cameron Berkenpas <cam@neo-zeon.de>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Tested-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Zefan Li <lizefan@huawei.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Cong Wang   authored and   Greg Kroah-Hartman   commited 2020-07-22 09:32:00 +02:00
0505cc4c90
bpf: Check correct cred for CAP_SYSLOG in bpf_dump_raw_ok()
commit 63960260457a02af2a6cb35d75e6bdb17299c882 upstream.

When evaluating access control over kallsyms visibility, credentials at
open() time need to be used, not the "current" creds (though in BPF's
case, this has likely always been the same). Plumb access to associated
file->f_cred down through bpf_dump_raw_ok() and its callers now that
kallsysm_show_value() has been refactored to take struct cred.

Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: bpf@vger.kernel.org
Cc: stable@vger.kernel.org
Fixes: 7105e828c0 ("bpf: allow for correlation of maps and helpers in dump")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Kees Cook   authored and   Greg Kroah-Hartman   commited 2020-07-16 08:17:27 +02:00
b80e052c3a
net: Do not clear the sock TX queue in sk_set_socket()
[ Upstream commit 41b14fb8724d5a4b382a63cb4a1a61880347ccb8 ]

Clearing the sock TX queue in sk_set_socket() might cause unexpected
out-of-order transmit when called from sock_orphan(), as outstanding
packets can pick a different TX queue and bypass the ones already queued.

This is undesired in general. More specifically, it breaks the in-order
scheduling property guarantee for device-offloaded TLS sockets.

Remove the call to sk_tx_queue_clear() in sk_set_socket(), and add it
explicitly only where needed.

Fixes: e022f0b4a0 ("net: Introduce sk_tx_queue_mapping")
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Tariq Toukan   authored and   Sasha Levin   commited 2020-06-30 23:17:06 -04:00
5104916360
net: increment xmit_recursion level in dev_direct_xmit()
[ Upstream commit 0ad6f6e767ec2f613418cbc7ebe5ec4c35af540c ]

Back in commit f60e5990d9 ("ipv6: protect skb->sk accesses
from recursive dereference inside the stack") Hannes added code
so that IPv6 stack would not trust skb->sk for typical cases
where packet goes through 'standard' xmit path (__dev_queue_xmit())

Alas af_packet had a dev_direct_xmit() path that was not
dealing yet with xmit_recursion level.

Also change sk_mc_loop() to dump a stack once only.

Without this patch, syzbot was able to trigger :

[1]
[  153.567378] WARNING: CPU: 7 PID: 11273 at net/core/sock.c:721 sk_mc_loop+0x51/0x70
[  153.567378] Modules linked in: nfnetlink ip6table_raw ip6table_filter iptable_raw iptable_nat nf_nat nf_conntrack nf_defrag_ipv4 nf_defrag_ipv6 iptable_filter macsec macvtap tap macvlan 8021q hsr wireguard libblake2s blake2s_x86_64 libblake2s_generic udp_tunnel ip6_udp_tunnel libchacha20poly1305 poly1305_x86_64 chacha_x86_64 libchacha curve25519_x86_64 libcurve25519_generic netdevsim batman_adv dummy team bridge stp llc w1_therm wire i2c_mux_pca954x i2c_mux cdc_acm ehci_pci ehci_hcd mlx4_en mlx4_ib ib_uverbs ib_core mlx4_core
[  153.567386] CPU: 7 PID: 11273 Comm: b159172088 Not tainted 5.8.0-smp-DEV #273
[  153.567387] RIP: 0010:sk_mc_loop+0x51/0x70
[  153.567388] Code: 66 83 f8 0a 75 24 0f b6 4f 12 b8 01 00 00 00 31 d2 d3 e0 a9 bf ef ff ff 74 07 48 8b 97 f0 02 00 00 0f b6 42 3a 83 e0 01 5d c3 <0f> 0b b8 01 00 00 00 5d c3 0f b6 87 18 03 00 00 5d c0 e8 04 83 e0
[  153.567388] RSP: 0018:ffff95c69bb93990 EFLAGS: 00010212
[  153.567388] RAX: 0000000000000011 RBX: ffff95c6e0ee3e00 RCX: 0000000000000007
[  153.567389] RDX: ffff95c69ae50000 RSI: ffff95c6c30c3000 RDI: ffff95c6c30c3000
[  153.567389] RBP: ffff95c69bb93990 R08: ffff95c69a77f000 R09: 0000000000000008
[  153.567389] R10: 0000000000000040 R11: 00003e0e00026128 R12: ffff95c6c30c3000
[  153.567390] R13: ffff95c6cc4fd500 R14: ffff95c6f84500c0 R15: ffff95c69aa13c00
[  153.567390] FS:  00007fdc3a283700(0000) GS:ffff95c6ff9c0000(0000) knlGS:0000000000000000
[  153.567390] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  153.567391] CR2: 00007ffee758e890 CR3: 0000001f9ba20003 CR4: 00000000001606e0
[  153.567391] Call Trace:
[  153.567391]  ip6_finish_output2+0x34e/0x550
[  153.567391]  __ip6_finish_output+0xe7/0x110
[  153.567391]  ip6_finish_output+0x2d/0xb0
[  153.567392]  ip6_output+0x77/0x120
[  153.567392]  ? __ip6_finish_output+0x110/0x110
[  153.567392]  ip6_local_out+0x3d/0x50
[  153.567392]  ipvlan_queue_xmit+0x56c/0x5e0
[  153.567393]  ? ksize+0x19/0x30
[  153.567393]  ipvlan_start_xmit+0x18/0x50
[  153.567393]  dev_direct_xmit+0xf3/0x1c0
[  153.567393]  packet_direct_xmit+0x69/0xa0
[  153.567394]  packet_sendmsg+0xbf0/0x19b0
[  153.567394]  ? plist_del+0x62/0xb0
[  153.567394]  sock_sendmsg+0x65/0x70
[  153.567394]  sock_write_iter+0x93/0xf0
[  153.567394]  new_sync_write+0x18e/0x1a0
[  153.567395]  __vfs_write+0x29/0x40
[  153.567395]  vfs_write+0xb9/0x1b0
[  153.567395]  ksys_write+0xb1/0xe0
[  153.567395]  __x64_sys_write+0x1a/0x20
[  153.567395]  do_syscall_64+0x43/0x70
[  153.567396]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  153.567396] RIP: 0033:0x453549
[  153.567396] Code: Bad RIP value.
[  153.567396] RSP: 002b:00007fdc3a282cc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[  153.567397] RAX: ffffffffffffffda RBX: 00000000004d32d0 RCX: 0000000000453549
[  153.567397] RDX: 0000000000000020 RSI: 0000000020000300 RDI: 0000000000000003
[  153.567398] RBP: 00000000004d32d8 R08: 0000000000000000 R09: 0000000000000000
[  153.567398] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004d32dc
[  153.567398] R13: 00007ffee742260f R14: 00007fdc3a282dc0 R15: 00007fdc3a283700
[  153.567399] ---[ end trace c1d5ae2b1059ec62 ]---

f60e5990d9 ("ipv6: protect skb->sk accesses from recursive dereference inside the stack")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Eric Dumazet   authored and   Sasha Levin   commited 2020-06-30 23:17:04 -04:00
220e80d937
net: place xmit recursion in softnet data
commit 97cdcf37b57e3f204be3000b9eab9686f38b4356 upstream.

This fills a hole in softnet data, so no change in structure size.

Also prepares for xmit_more placement in the same spot;
skb->xmit_more will be removed in followup patch.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Florian Westphal   authored and   Sasha Levin   commited 2020-06-30 23:17:04 -04:00
edbe653223
net: fix memleak in register_netdevice()
[ Upstream commit 814152a89ed52c722ab92e9fbabcac3cb8a39245 ]

I got a memleak report when doing some fuzz test:

unreferenced object 0xffff888112584000 (size 13599):
  comm "ip", pid 3048, jiffies 4294911734 (age 343.491s)
  hex dump (first 32 bytes):
    74 61 70 30 00 00 00 00 00 00 00 00 00 00 00 00  tap0............
    00 ee d9 19 81 88 ff ff 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<000000002f60ba65>] __kmalloc_node+0x309/0x3a0
    [<0000000075b211ec>] kvmalloc_node+0x7f/0xc0
    [<00000000d3a97396>] alloc_netdev_mqs+0x76/0xfc0
    [<00000000609c3655>] __tun_chr_ioctl+0x1456/0x3d70
    [<000000001127ca24>] ksys_ioctl+0xe5/0x130
    [<00000000b7d5e66a>] __x64_sys_ioctl+0x6f/0xb0
    [<00000000e1023498>] do_syscall_64+0x56/0xa0
    [<000000009ec0eb12>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
unreferenced object 0xffff888111845cc0 (size 8):
  comm "ip", pid 3048, jiffies 4294911734 (age 343.491s)
  hex dump (first 8 bytes):
    74 61 70 30 00 88 ff ff                          tap0....
  backtrace:
    [<000000004c159777>] kstrdup+0x35/0x70
    [<00000000d8b496ad>] kstrdup_const+0x3d/0x50
    [<00000000494e884a>] kvasprintf_const+0xf1/0x180
    [<0000000097880a2b>] kobject_set_name_vargs+0x56/0x140
    [<000000008fbdfc7b>] dev_set_name+0xab/0xe0
    [<000000005b99e3b4>] netdev_register_kobject+0xc0/0x390
    [<00000000602704fe>] register_netdevice+0xb61/0x1250
    [<000000002b7ca244>] __tun_chr_ioctl+0x1cd1/0x3d70
    [<000000001127ca24>] ksys_ioctl+0xe5/0x130
    [<00000000b7d5e66a>] __x64_sys_ioctl+0x6f/0xb0
    [<00000000e1023498>] do_syscall_64+0x56/0xa0
    [<000000009ec0eb12>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
unreferenced object 0xffff88811886d800 (size 512):
  comm "ip", pid 3048, jiffies 4294911734 (age 343.491s)
  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 c0 66 3d a3 ff ff ff ff  .........f=.....
  backtrace:
    [<0000000050315800>] device_add+0x61e/0x1950
    [<0000000021008dfb>] netdev_register_kobject+0x17e/0x390
    [<00000000602704fe>] register_netdevice+0xb61/0x1250
    [<000000002b7ca244>] __tun_chr_ioctl+0x1cd1/0x3d70
    [<000000001127ca24>] ksys_ioctl+0xe5/0x130
    [<00000000b7d5e66a>] __x64_sys_ioctl+0x6f/0xb0
    [<00000000e1023498>] do_syscall_64+0x56/0xa0
    [<000000009ec0eb12>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

If call_netdevice_notifiers() failed, then rollback_registered()
calls netdev_unregister_kobject() which holds the kobject. The
reference cannot be put because the netdev won't be add to todo
list, so it will leads a memleak, we need put the reference to
avoid memleak.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Yang Yingliang   authored and   Sasha Levin   commited 2020-06-30 23:17:03 -04:00
061abde395
net: core: device_rename: Use rwsem instead of a seqcount
[ Upstream commit 11d6011c2cf29f7c8181ebde6c8bc0c4d83adcd7 ]

Sequence counters write paths are critical sections that must never be
preempted, and blocking, even for CONFIG_PREEMPTION=n, is not allowed.

Commit 5dbe7c178d ("net: fix kernel deadlock with interface rename and
netdev name retrieval.") handled a deadlock, observed with
CONFIG_PREEMPTION=n, where the devnet_rename seqcount read side was
infinitely spinning: it got scheduled after the seqcount write side
blocked inside its own critical section.

To fix that deadlock, among other issues, the commit added a
cond_resched() inside the read side section. While this will get the
non-preemptible kernel eventually unstuck, the seqcount reader is fully
exhausting its slice just spinning -- until TIF_NEED_RESCHED is set.

The fix is also still broken: if the seqcount reader belongs to a
real-time scheduling policy, it can spin forever and the kernel will
livelock.

Disabling preemption over the seqcount write side critical section will
not work: inside it are a number of GFP_KERNEL allocations and mutex
locking through the drivers/base/ :: device_rename() call chain.

>From all the above, replace the seqcount with a rwsem.

Fixes: 5dbe7c178d (net: fix kernel deadlock with interface rename and netdev name retrieval.)
Fixes: 30e6c9fa93 (net: devnet_rename_seq should be a seqcount)
Fixes: c91f6df2db (sockopt: Change getsockopt() of SO_BINDTODEVICE to return an interface name)
Cc: <stable@vger.kernel.org>
Reported-by: kbuild test robot <lkp@intel.com> [ v1 missing up_read() on error exit ]
Reported-by: Dan Carpenter <dan.carpenter@oracle.com> [ v1 missing up_read() on error exit ]
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Ahmed S. Darwish   authored and   Greg Kroah-Hartman   commited 2020-06-25 15:33:10 +02:00
29d1d0c724
sched/rt, net: Use CONFIG_PREEMPTION.patch
[ Upstream commit 2da2b32fd9346009e9acdb68c570ca8d3966aba7 ]

CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.

Update the comment to use CONFIG_PREEMPTION.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: netdev@vger.kernel.org
Link: https://lore.kernel.org/r/20191015191821.11479-22-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Thomas Gleixner   authored and   Greg Kroah-Hartman   commited 2020-06-25 15:33:10 +02:00
b855db2a12
net/filter: Permit reading NET in load_bytes_relative when MAC not set
[ Upstream commit 0f5d82f187e1beda3fe7295dfc500af266a5bd80 ]

Added a check in the switch case on start_header that checks for
the existence of the header, and in the case that MAC is not set
and the caller requests for MAC, -EFAULT. If the caller requests
for NET then MAC's existence is completely ignored.

There is no function to check NET header's existence and as far
as cgroup_skb/egress is concerned it should always be set.

Removed for ptr >= the start of header, considering offset is
bounded unsigned and should always be true. len <= end - mac is
redundant to ptr + len <= end.

Fixes: 3eee1f75f2 ("bpf: fix bpf_skb_load_bytes_relative pkt length check")
Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/76bb820ddb6a95f59a772ecbd8c8a336f646b362.1591812755.git.zhuyifei@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

YiFei Zhu   authored and   Greg Kroah-Hartman   commited 2020-06-25 15:33:05 +02:00
d326597751
__netif_receive_skb_core: pass skb by reference
[ Upstream commit c0bbbdc32febd4f034ecbf3ea17865785b2c0652 ]

__netif_receive_skb_core may change the skb pointer passed into it (e.g.
in rx_handler). The original skb may be freed as a result of this
operation.

The callers of __netif_receive_skb_core may further process original skb
by using pt_prev pointer returned by __netif_receive_skb_core thus
leading to unpleasant effects.

The solution is to pass skb by reference into __netif_receive_skb_core.

v2: Added Fixes tag and comment regarding ppt_prev and skb invariant.

Fixes: 88eb1944e1 ("net: core: propagate SKB lists through packet_type lookup")
Signed-off-by: Boris Sukholitko <boris.sukholitko@broadcom.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Boris Sukholitko   authored and   Greg Kroah-Hartman   commited 2020-06-03 08:19:05 +02:00
96b2f1c0b0
netprio_cgroup: Fix unlimited memory leak of v2 cgroups
[ Upstream commit 090e28b229af92dc5b40786ca673999d59e73056 ]

If systemd is configured to use hybrid mode which enables the use of
both cgroup v1 and v2, systemd will create new cgroup on both the default
root (v2) and netprio_cgroup hierarchy (v1) for a new session and attach
task to the two cgroups. If the task does some network thing then the v2
cgroup can never be freed after the session exited.

One of our machines ran into OOM due to this memory leak.

In the scenario described above when sk_alloc() is called
cgroup_sk_alloc() thought it's in v2 mode, so it stores
the cgroup pointer in sk->sk_cgrp_data and increments
the cgroup refcnt, but then sock_update_netprioidx()
thought it's in v1 mode, so it stores netprioidx value
in sk->sk_cgrp_data, so the cgroup refcnt will never be freed.

Currently we do the mode switch when someone writes to the ifpriomap
cgroup control file. The easiest fix is to also do the switch when
a task is attached to a new cgroup.

Fixes: bd1060a1d6 ("sock, cgroup: add sock->sk_cgroup")
Reported-by: Yang Yingliang <yangyingliang@huawei.com>
Tested-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Zefan Li <lizefan@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Zefan Li   authored and   Greg Kroah-Hartman   commited 2020-05-20 08:18:38 +02:00
0ccd250359
net: fix a potential recursive NETDEV_FEAT_CHANGE
[ Upstream commit dd912306ff008891c82cd9f63e8181e47a9cb2fb ]

syzbot managed to trigger a recursive NETDEV_FEAT_CHANGE event
between bonding master and slave. I managed to find a reproducer
for this:

  ip li set bond0 up
  ifenslave bond0 eth0
  brctl addbr br0
  ethtool -K eth0 lro off
  brctl addif br0 bond0
  ip li set br0 up

When a NETDEV_FEAT_CHANGE event is triggered on a bonding slave,
it captures this and calls bond_compute_features() to fixup its
master's and other slaves' features. However, when syncing with
its lower devices by netdev_sync_lower_features() this event is
triggered again on slaves when the LRO feature fails to change,
so it goes back and forth recursively until the kernel stack is
exhausted.

Commit 17b85d29e8 intentionally lets __netdev_update_features()
return -1 for such a failure case, so we have to just rely on
the existing check inside netdev_sync_lower_features() and skip
NETDEV_FEAT_CHANGE event only for this specific failure case.

Fixes: fd867d51f8 ("net/core: generic support for disabling netdev features down stack")
Reported-by: syzbot+e73ceacfd8560cc8a3ca@syzkaller.appspotmail.com
Reported-by: syzbot+c2fb6f9ddcea95ba49b5@syzkaller.appspotmail.com
Cc: Jarod Wilson <jarod@redhat.com>
Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jann Horn <jannh@google.com>
Reviewed-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Cong Wang   authored and   Greg Kroah-Hartman   commited 2020-05-20 08:18:35 +02:00
2ef834fec2
drop_monitor: work around gcc-10 stringop-overflow warning
[ Upstream commit dc30b4059f6e2abf3712ab537c8718562b21c45d ]

The current gcc-10 snapshot produces a false-positive warning:

net/core/drop_monitor.c: In function 'trace_drop_common.constprop':
cc1: error: writing 8 bytes into a region of size 0 [-Werror=stringop-overflow=]
In file included from net/core/drop_monitor.c:23:
include/uapi/linux/net_dropmon.h:36:8: note: at offset 0 to object 'entries' with size 4 declared here
   36 |  __u32 entries;
      |        ^~~~~~~

I reported this in the gcc bugzilla, but in case it does not get
fixed in the release, work around it by using a temporary variable.

Fixes: 9a8afc8d39 ("Network Drop Monitor: Adding drop monitor implementation & Netlink protocol")
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94881
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Arnd Bergmann   authored and   Greg Kroah-Hartman   commited 2020-05-20 08:18:33 +02:00
e459398d60
cgroup, netclassid: remove double cond_resched
commit 526f3d96b8f83b1b13d73bd0b5c79cc2c487ec8e upstream.

Commit 018d26fcd12a ("cgroup, netclassid: periodically release file_lock
on classid") added a second cond_resched to write_classid indirectly by
update_classid_task. Remove the one in write_classid.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Dmitry Yakunin <zeil@yandex-team.ru>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jiri Slaby   authored and   Greg Kroah-Hartman   commited 2020-05-10 10:30:12 +02:00
1e08af942a
net: revert default NAPI poll timeout to 2 jiffies
[ Upstream commit a4837980fd9fa4c70a821d11831698901baef56b ]

For HZ < 1000 timeout 2000us rounds up to 1 jiffy but expires randomly
because next timer interrupt could come shortly after starting softirq.

For commonly used CONFIG_HZ=1000 nothing changes.

Fixes: 7acf8a1e8a ("Replace 2 jiffies with sysctl netdev_budget_usecs to enable softirq tuning")
Reported-by: Dmitry Yakunin <zeil@yandex-team.ru>
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Konstantin Khlebnikov   authored and   Greg Kroah-Hartman   commited 2020-04-21 09:03:04 +02:00
f7379c0050
net: Fix Tx hash bound checking
commit 6e11d1578fba8d09d03a286740ffcf336d53928c upstream.

Fixes the lower and upper bounds when there are multiple TCs and
traffic is on the the same TC on the same device.

The lower bound is represented by 'qoffset' and the upper limit for
hash value is 'qcount + qoffset'. This gives a clean Rx to Tx queue
mapping when there are multiple TCs, as the queue indices for upper TCs
will be offset by 'qoffset'.

v2: Fixed commit description based on comments.

Fixes: 1b837d489e ("net: Revoke export for __skb_tx_hash, update it to just be static skb_tx_hash")
Fixes: eadec877ce ("net: Add support for subordinate traffic classes to netdev_pick_tx")
Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Amritha Nambiar   authored and   Greg Kroah-Hartman   commited 2020-04-13 10:45:05 +02:00
b1cb7f2bc9
devlink: validate length of region addr/len
[ Upstream commit ff3b63b8c299b73ac599b120653b47e275407656 ]

DEVLINK_ATTR_REGION_CHUNK_ADDR and DEVLINK_ATTR_REGION_CHUNK_LEN
lack entries in the netlink policy. Corresponding nla_get_u64()s
may read beyond the end of the message.

Fixes: 4e54795a27 ("devlink: Add support for region snapshot read command")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jakub Kicinski   authored and   Greg Kroah-Hartman   commited 2020-03-18 07:14:18 +01:00
48aea14b88
devlink: validate length of param values
[ Upstream commit 8750939b6ad86abc3f53ec8a9683a1cded4a5654 ]

DEVLINK_ATTR_PARAM_VALUE_DATA may have different types
so it's not checked by the normal netlink policy. Make
sure the attribute length is what we expect.

Fixes: e3b7ca18ad ("devlink: Add param set command")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jakub Kicinski   authored and   Greg Kroah-Hartman   commited 2020-03-18 07:14:14 +01:00
f9f04772a2
net: memcg: late association of sock to memcg
[ Upstream commit d752a4986532cb6305dfd5290a614cde8072769d ]

If a TCP socket is allocated in IRQ context or cloned from unassociated
(i.e. not associated to a memcg) in IRQ context then it will remain
unassociated for its whole life. Almost half of the TCPs created on the
system are created in IRQ context, so, memory used by such sockets will
not be accounted by the memcg.

This issue is more widespread in cgroup v1 where network memory
accounting is opt-in but it can happen in cgroup v2 if the source socket
for the cloning was created in root memcg.

To fix the issue, just do the association of the sockets at the accept()
time in the process context and then force charge the memory buffer
already used and reserved by the socket.

Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Shakeel Butt   authored and   Greg Kroah-Hartman   commited 2020-03-18 07:14:14 +01:00
9d9141948a
cgroup, netclassid: periodically release file_lock on classid updating
[ Upstream commit 018d26fcd12a75fb9b5fe233762aa3f2f0854b88 ]

In our production environment we have faced with problem that updating
classid in cgroup with heavy tasks cause long freeze of the file tables
in this tasks. By heavy tasks we understand tasks with many threads and
opened sockets (e.g. balancers). This freeze leads to an increase number
of client timeouts.

This patch implements following logic to fix this issue:
аfter iterating 1000 file descriptors file table lock will be released
thus providing a time gap for socket creation/deletion.

Now update is non atomic and socket may be skipped using calls:

dup2(oldfd, newfd);
close(oldfd);

But this case is not typical. Moreover before this patch skip is possible
too by hiding socket fd in unix socket buffer.

New sockets will be allocated with updated classid because cgroup state
is updated before start of the file descriptors iteration.

So in common cases this patch has no side effects.

Signed-off-by: Dmitry Yakunin <zeil@yandex-team.ru>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Dmitry Yakunin   authored and   Greg Kroah-Hartman   commited 2020-03-18 07:14:10 +01:00
d6d11db20e
net: fib_rules: Correctly set table field when table number exceeds 8 bits
[ Upstream commit 540e585a79e9d643ede077b73bcc7aa2d7b4d919 ]

In 709772e6e0, RT_TABLE_COMPAT was added to
allow legacy software to deal with routing table numbers >= 256, but the
same change to FIB rule queries was overlooked.

Signed-off-by: Jethro Beekman <jethro@fortanix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jethro Beekman   authored and   Greg Kroah-Hartman   commited 2020-03-05 16:42:15 +01:00
75515736cd
bpf: Return -EBADRQC for invalid map type in __bpf_tx_xdp_map
[ Upstream commit 0a29275b6300f39f78a87f2038bbfe5bdbaeca47 ]

A negative value should be returned if map->map_type is invalid
although that is impossible now, but if we run into such situation
in future, then xdpbuff could be leaked.

Daniel Borkmann suggested:

-EBADRQC should be returned to stay consistent with generic XDP
for the tracepoint output and not to be confused with -EOPNOTSUPP
from other locations like dev_map_enqueue() when ndo_xdp_xmit is
missing and such.

Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1578618277-18085-1-git-send-email-lirongqing@baidu.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

Li RongQing   authored and   Greg Kroah-Hartman   commited 2020-02-24 08:34:47 +01:00
1bb30a41da
core: Don't skip generic XDP program execution for cloned SKBs
[ Upstream commit ad1e03b2b3d4430baaa109b77bc308dc73050de3 ]

The current generic XDP handler skips execution of XDP programs entirely if
an SKB is marked as cloned. This leads to some surprising behaviour, as
packets can end up being cloned in various ways, which will make an XDP
program not see all the traffic on an interface.

This was discovered by a simple test case where an XDP program that always
returns XDP_DROP is installed on a veth device. When combining this with
the Scapy packet sniffer (which uses an AF_PACKET) socket on the sending
side, SKBs reliably end up in the cloned state, causing them to be passed
through to the receiving interface instead of being dropped. A minimal
reproducer script for this is included below.

This patch fixed the issue by simply triggering the existing linearisation
code for cloned SKBs instead of skipping the XDP program execution. This
behaviour is in line with the behaviour of the native XDP implementation
for the veth driver, which will reallocate and copy the SKB data if the SKB
is marked as shared.

Reproducer Python script (requires BCC and Scapy):

from scapy.all import TCP, IP, Ether, sendp, sniff, AsyncSniffer, Raw, UDP
from bcc import BPF
import time, sys, subprocess, shlex

SKB_MODE = (1 << 1)
DRV_MODE = (1 << 2)
PYTHON=sys.executable

def client():
    time.sleep(2)
    # Sniffing on the sender causes skb_cloned() to be set
    s = AsyncSniffer()
    s.start()

    for p in range(10):
        sendp(Ether(dst="aa:aa:aa:aa:aa:aa", src="cc:cc:cc:cc:cc:cc")/IP()/UDP()/Raw("Test"),
              verbose=False)
        time.sleep(0.1)

    s.stop()
    return 0

def server(mode):
    prog = BPF(text="int dummy_drop(struct xdp_md *ctx) {return XDP_DROP;}")
    func = prog.load_func("dummy_drop", BPF.XDP)
    prog.attach_xdp("a_to_b", func, mode)

    time.sleep(1)

    s = sniff(iface="a_to_b", count=10, timeout=15)
    if len(s):
        print(f"Got {len(s)} packets - should have gotten 0")
        return 1
    else:
        print("Got no packets - as expected")
        return 0

if len(sys.argv) < 2:
    print(f"Usage: {sys.argv[0]} <skb|drv>")
    sys.exit(1)

if sys.argv[1] == "client":
    sys.exit(client())
elif sys.argv[1] == "server":
    mode = SKB_MODE if sys.argv[2] == 'skb' else DRV_MODE
    sys.exit(server(mode))
else:
    try:
        mode = sys.argv[1]
        if mode not in ('skb', 'drv'):
            print(f"Usage: {sys.argv[0]} <skb|drv>")
            sys.exit(1)
        print(f"Running in {mode} mode")

        for cmd in [
                'ip netns add netns_a',
                'ip netns add netns_b',
                'ip -n netns_a link add a_to_b type veth peer name b_to_a netns netns_b',
                # Disable ipv6 to make sure there's no address autoconf traffic
                'ip netns exec netns_a sysctl -qw net.ipv6.conf.a_to_b.disable_ipv6=1',
                'ip netns exec netns_b sysctl -qw net.ipv6.conf.b_to_a.disable_ipv6=1',
                'ip -n netns_a link set dev a_to_b address aa:aa:aa:aa:aa:aa',
                'ip -n netns_b link set dev b_to_a address cc:cc:cc:cc:cc:cc',
                'ip -n netns_a link set dev a_to_b up',
                'ip -n netns_b link set dev b_to_a up']:
            subprocess.check_call(shlex.split(cmd))

        server = subprocess.Popen(shlex.split(f"ip netns exec netns_a {PYTHON} {sys.argv[0]} server {mode}"))
        client = subprocess.Popen(shlex.split(f"ip netns exec netns_b {PYTHON} {sys.argv[0]} client"))

        client.wait()
        server.wait()
        sys.exit(server.returncode)

    finally:
        subprocess.run(shlex.split("ip netns delete netns_a"))
        subprocess.run(shlex.split("ip netns delete netns_b"))

Fixes: d445516966 ("net: xdp: support xdp generic on virtual devices")
Reported-by: Stepan Horacek <shoracek@redhat.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Toke Høiland-Jørgensen   authored and   Greg Kroah-Hartman   commited 2020-02-24 08:34:34 +01:00
ce754a3149
net: Fix skb->csum update in inet_proto_csum_replace16().
[ Upstream commit 189c9b1e94539b11c80636bc13e9cf47529e7bba ]

skb->csum is updated incorrectly, when manipulation for
NF_NAT_MANIP_SRC\DST is done on IPV6 packet.

Fix:
There is no need to update skb->csum in inet_proto_csum_replace16(),
because update in two fields a.) IPv6 src/dst address and b.) L4 header
checksum cancels each other for skb->csum calculation. Whereas
inet_proto_csum_replace4 function needs to update skb->csum, because
update in 3 fields a.) IPv4 src/dst address, b.) IPv4 Header checksum
and c.) L4 header checksum results in same diff as L4 Header checksum
for skb->csum calculation.

[ pablo@netfilter.org: a few comestic documentation edits ]
Signed-off-by: Praveen Chaudhary <pchaudhary@linkedin.com>
Signed-off-by: Zhenggen Xu <zxu@linkedin.com>
Signed-off-by: Andy Stracner <astracner@linkedin.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Praveen Chaudhary   authored and   Greg Kroah-Hartman   commited 2020-02-05 14:43:53 +00:00
7e4d3a8c48
net-sysfs: Fix reference count leak
[ Upstream commit cb626bf566eb4433318d35681286c494f04fedcc ]

Netdev_register_kobject is calling device_initialize. In case of error
reference taken by device_initialize is not given up.

Drivers are supposed to call free_netdev in case of error. In non-error
case the last reference is given up there and device release sequence
is triggered. In error case this reference is kept and the release
sequence is never started.

Fix this by setting reg_state as NETREG_UNREGISTERED if registering
fails.

This is the rootcause for couple of memory leaks reported by Syzkaller:

BUG: memory leak unreferenced object 0xffff8880675ca008 (size 256):
  comm "netdev_register", pid 281, jiffies 4294696663 (age 6.808s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
  backtrace:
    [<0000000058ca4711>] kmem_cache_alloc_trace+0x167/0x280
    [<000000002340019b>] device_add+0x882/0x1750
    [<000000001d588c3a>] netdev_register_kobject+0x128/0x380
    [<0000000011ef5535>] register_netdevice+0xa1b/0xf00
    [<000000007fcf1c99>] __tun_chr_ioctl+0x20d5/0x3dd0
    [<000000006a5b7b2b>] tun_chr_ioctl+0x2f/0x40
    [<00000000f30f834a>] do_vfs_ioctl+0x1c7/0x1510
    [<00000000fba062ea>] ksys_ioctl+0x99/0xb0
    [<00000000b1c1b8d2>] __x64_sys_ioctl+0x78/0xb0
    [<00000000984cabb9>] do_syscall_64+0x16f/0x580
    [<000000000bde033d>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
    [<00000000e6ca2d9f>] 0xffffffffffffffff

BUG: memory leak
unreferenced object 0xffff8880668ba588 (size 8):
  comm "kobject_set_nam", pid 286, jiffies 4294725297 (age 9.871s)
  hex dump (first 8 bytes):
    6e 72 30 00 cc be df 2b                          nr0....+
  backtrace:
    [<00000000a322332a>] __kmalloc_track_caller+0x16e/0x290
    [<00000000236fd26b>] kstrdup+0x3e/0x70
    [<00000000dd4a2815>] kstrdup_const+0x3e/0x50
    [<0000000049a377fc>] kvasprintf_const+0x10e/0x160
    [<00000000627fc711>] kobject_set_name_vargs+0x5b/0x140
    [<0000000019eeab06>] dev_set_name+0xc0/0xf0
    [<0000000069cb12bc>] netdev_register_kobject+0xc8/0x320
    [<00000000f2e83732>] register_netdevice+0xa1b/0xf00
    [<000000009e1f57cc>] __tun_chr_ioctl+0x20d5/0x3dd0
    [<000000009c560784>] tun_chr_ioctl+0x2f/0x40
    [<000000000d759e02>] do_vfs_ioctl+0x1c7/0x1510
    [<00000000351d7c31>] ksys_ioctl+0x99/0xb0
    [<000000008390040a>] __x64_sys_ioctl+0x78/0xb0
    [<0000000052d196b7>] do_syscall_64+0x16f/0x580
    [<0000000019af9236>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
    [<00000000bc384531>] 0xffffffffffffffff

v3 -> v4:
  Set reg_state to NETREG_UNREGISTERED if registering fails

v2 -> v3:
* Replaced BUG_ON with WARN_ON in free_netdev and netdev_release

v1 -> v2:
* Relying on driver calling free_netdev rather than calling
  put_device directly in error path

Reported-by: syzbot+ad8ca40ecd77896d51e2@syzkaller.appspotmail.com
Cc: David Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Jouni Hogander <jouni.hogander@unikie.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jouni Hogander   authored and   Greg Kroah-Hartman   commited 2020-01-29 16:43:17 +01:00
b4b0f1fc19
net-sysfs: Call dev_hold always in rx_queue_add_kobject
commit ddd9b5e3e765d8ed5a35786a6cb00111713fe161 upstream.

Dev_hold has to be called always in rx_queue_add_kobject.
Otherwise usage count drops below 0 in case of failure in
kobject_init_and_add.

Fixes: b8eb718348b8 ("net-sysfs: Fix reference count leak in rx|netdev_queue_add_kobject")
Reported-by: syzbot <syzbot+30209ea299c09d8785c9@syzkaller.appspotmail.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: David Miller <davem@davemloft.net>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Jouni Hogander <jouni.hogander@unikie.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jouni Hogander   authored and   Greg Kroah-Hartman   commited 2020-01-29 16:43:17 +01:00
33c540f663
net-sysfs: Call dev_hold always in netdev_queue_add_kobject
commit e0b60903b434a7ee21ba8d8659f207ed84101e89 upstream.

Dev_hold has to be called always in netdev_queue_add_kobject.
Otherwise usage count drops below 0 in case of failure in
kobject_init_and_add.

Fixes: b8eb718348b8 ("net-sysfs: Fix reference count leak in rx|netdev_queue_add_kobject")
Reported-by: Hulk Robot <hulkci@huawei.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: David Miller <davem@davemloft.net>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jouni Hogander   authored and   Greg Kroah-Hartman   commited 2020-01-29 16:43:16 +01:00
f8862bc44f
net-sysfs: fix netdev_queue_add_kobject() breakage
commit 48a322b6f9965b2f1e4ce81af972f0e287b07ed0 upstream.

kobject_put() should only be called in error path.

Fixes: b8eb718348b8 ("net-sysfs: Fix reference count leak in rx|netdev_queue_add_kobject")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jouni Hogander <jouni.hogander@unikie.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Eric Dumazet   authored and   Greg Kroah-Hartman   commited 2020-01-29 16:43:16 +01:00
7070695e60
net-sysfs: Fix reference count leak in rx|netdev_queue_add_kobject
commit b8eb718348b8fb30b5a7d0a8fce26fb3f4ac741b upstream.

kobject_init_and_add takes reference even when it fails. This has
to be given up by the caller in error handling. Otherwise memory
allocated by kobject_init_and_add is never freed. Originally found
by Syzkaller:

BUG: memory leak
unreferenced object 0xffff8880679f8b08 (size 8):
  comm "netdev_register", pid 269, jiffies 4294693094 (age 12.132s)
  hex dump (first 8 bytes):
    72 78 2d 30 00 36 20 d4                          rx-0.6 .
  backtrace:
    [<000000008c93818e>] __kmalloc_track_caller+0x16e/0x290
    [<000000001f2e4e49>] kvasprintf+0xb1/0x140
    [<000000007f313394>] kvasprintf_const+0x56/0x160
    [<00000000aeca11c8>] kobject_set_name_vargs+0x5b/0x140
    [<0000000073a0367c>] kobject_init_and_add+0xd8/0x170
    [<0000000088838e4b>] net_rx_queue_update_kobjects+0x152/0x560
    [<000000006be5f104>] netdev_register_kobject+0x210/0x380
    [<00000000e31dab9d>] register_netdevice+0xa1b/0xf00
    [<00000000f68b2465>] __tun_chr_ioctl+0x20d5/0x3dd0
    [<000000004c50599f>] tun_chr_ioctl+0x2f/0x40
    [<00000000bbd4c317>] do_vfs_ioctl+0x1c7/0x1510
    [<00000000d4c59e8f>] ksys_ioctl+0x99/0xb0
    [<00000000946aea81>] __x64_sys_ioctl+0x78/0xb0
    [<0000000038d946e5>] do_syscall_64+0x16f/0x580
    [<00000000e0aa5d8f>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
    [<00000000285b3d1a>] 0xffffffffffffffff

Cc: David Miller <davem@davemloft.net>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Jouni Hogander <jouni.hogander@unikie.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jouni Hogander   authored and   Greg Kroah-Hartman   commited 2020-01-29 16:43:16 +01:00
60e7154661
net: rtnetlink: validate IFLA_MTU attribute in rtnl_create_link()
[ Upstream commit d836f5c69d87473ff65c06a6123e5b2cf5e56f5b ]

rtnl_create_link() needs to apply dev->min_mtu and dev->max_mtu
checks that we apply in do_setlink()

Otherwise malicious users can crash the kernel, for example after
an integer overflow :

BUG: KASAN: use-after-free in memset include/linux/string.h:365 [inline]
BUG: KASAN: use-after-free in __alloc_skb+0x37b/0x5e0 net/core/skbuff.c:238
Write of size 32 at addr ffff88819f20b9c0 by task swapper/0/0

CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x197/0x210 lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:639
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192
 memset+0x24/0x40 mm/kasan/common.c:108
 memset include/linux/string.h:365 [inline]
 __alloc_skb+0x37b/0x5e0 net/core/skbuff.c:238
 alloc_skb include/linux/skbuff.h:1049 [inline]
 alloc_skb_with_frags+0x93/0x590 net/core/skbuff.c:5664
 sock_alloc_send_pskb+0x7ad/0x920 net/core/sock.c:2242
 sock_alloc_send_skb+0x32/0x40 net/core/sock.c:2259
 mld_newpack+0x1d7/0x7f0 net/ipv6/mcast.c:1609
 add_grhead.isra.0+0x299/0x370 net/ipv6/mcast.c:1713
 add_grec+0x7db/0x10b0 net/ipv6/mcast.c:1844
 mld_send_cr net/ipv6/mcast.c:1970 [inline]
 mld_ifc_timer_expire+0x3d3/0x950 net/ipv6/mcast.c:2477
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x6c3/0x1790 kernel/time/timer.c:1786
 __do_softirq+0x262/0x98c kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x19b/0x1e0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: 98 6b ea f9 eb 8a cc cc cc cc cc cc e9 07 00 00 00 0f 00 2d 44 1c 60 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 34 1c 60 00 fb f4 <c3> cc 55 48 89 e5 41 57 41 56 41 55 41 54 53 e8 4e 5d 9a f9 e8 79
RSP: 0018:ffffffff89807ce8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff13266ae RBX: ffffffff8987a1c0 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffffffff8987aa54
RBP: ffffffff89807d18 R08: ffffffff8987a1c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
R13: ffffffff8a799980 R14: 0000000000000000 R15: 0000000000000000
 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:690
 default_idle_call+0x84/0xb0 kernel/sched/idle.c:94
 cpuidle_idle_call kernel/sched/idle.c:154 [inline]
 do_idle+0x3c8/0x6e0 kernel/sched/idle.c:269
 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:361
 rest_init+0x23b/0x371 init/main.c:451
 arch_call_rest_init+0xe/0x1b
 start_kernel+0x904/0x943 init/main.c:784
 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:490
 x86_64_start_kernel+0x77/0x7b arch/x86/kernel/head64.c:471
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242

The buggy address belongs to the page:
page:ffffea00067c82c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
raw: 057ffe0000000000 ffffea00067c82c8 ffffea00067c82c8 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88819f20b880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88819f20b900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88819f20b980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                           ^
 ffff88819f20ba00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88819f20ba80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

Fixes: 61e84623ac ("net: centralize net_device min/max MTU checking")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Eric Dumazet   authored and   Greg Kroah-Hartman   commited 2020-01-29 16:43:16 +01:00
be1a2be7a7
net: neigh: use long type to store jiffies delta
[ Upstream commit 9d027e3a83f39b819e908e4e09084277a2e45e95 ]

A difference of two unsigned long needs long storage.

Fixes: c7fb64db00 ("[NETLINK]: Neighbour table configuration and statistics via rtnetlink")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Eric Dumazet   authored and   Greg Kroah-Hartman   commited 2020-01-27 14:51:21 +01:00
d261a03d8c
net: avoid possible false sharing in sk_leave_memory_pressure()
[ Upstream commit 503978aca46124cd714703e180b9c8292ba50ba7 ]

As mentioned in https://github.com/google/ktsan/wiki/READ_ONCE-and-WRITE_ONCE#it-may-improve-performance
a C compiler can legally transform :

if (memory_pressure && *memory_pressure)
        *memory_pressure = 0;

to :

if (memory_pressure)
        *memory_pressure = 0;

Fixes: 0604475119 ("tcp: add TCPMemoryPressuresChrono counter")
Fixes: 180d8cd942 ("foundations of per-cgroup memory pressure controlling.")
Fixes: 3ab224be6d ("[NET] CORE: Introducing new memory accounting interface.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Eric Dumazet   authored and   Greg Kroah-Hartman   commited 2020-01-27 14:51:18 +01:00
910699a81f
net: fix bpf_xdp_adjust_head regression for generic-XDP
[ Upstream commit 065af355470519bd184019a93ac579f22b036045 ]

When generic-XDP was moved to a later processing step by commit
458bf2f224f0 ("net: core: support XDP generic on stacked devices.")
a regression was introduced when using bpf_xdp_adjust_head.

The issue is that after this commit the skb->network_header is now
changed prior to calling generic XDP and not after. Thus, if the header
is changed by XDP (via bpf_xdp_adjust_head), then skb->network_header
also need to be updated again.  Fix by calling skb_reset_network_header().

Fixes: 458bf2f224f0 ("net: core: support XDP generic on stacked devices.")
Reported-by: Brandon Cazander <brandon.cazander@multapplied.net>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Jesper Dangaard Brouer   authored and   Greg Kroah-Hartman   commited 2020-01-27 14:51:03 +01:00
50176c0d22
bpf: fix the check that forwarding is enabled in bpf_ipv6_fib_lookup
[ Upstream commit 56f0f84e69c7a7f229dfa524b13b0ceb6ce9b09e ]

The bpf_ipv6_fib_lookup function should return BPF_FIB_LKUP_RET_FWD_DISABLED
when forwarding is disabled for the input device.  However instead of checking
if forwarding is enabled on the input device, it checked the global
net->ipv6.devconf_all->forwarding flag.  Change it to behave as expected.

Fixes: 87f5fc7e48 ("bpf: Provide helper to do forwarding lookups in kernel FIB table")
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Anton Protopopov   authored and   Greg Kroah-Hartman   commited 2020-01-27 14:50:55 +01:00
59a7ecd9d2
net: core: support XDP generic on stacked devices.
[ Upstream commit 458bf2f224f04a513b0be972f8708e78ee2c986e ]

When a device is stacked like (team, bonding, failsafe or netvsc) the
XDP generic program for the parent device was not called.

Move the call to XDP generic inside __netif_receive_skb_core where
it can be done multiple times for stacked case.

Fixes: d445516966 ("net: xdp: support xdp generic on virtual devices")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Stephen Hemminger   authored and   Greg Kroah-Hartman   commited 2020-01-27 14:50:52 +01:00
6c350e974c
ethtool: reduce stack usage with clang
commit 3499e87ea0413ee5b2cc028f4c8ed4d424bc7f98 upstream.

clang inlines the dev_ethtool() more aggressively than gcc does, leading
to a larger amount of used stack space:

net/core/ethtool.c:2536:24: error: stack frame size of 1216 bytes in function 'dev_ethtool' [-Werror,-Wframe-larger-than=]

Marking the sub-functions that require the most stack space as
noinline_for_stack gives us reasonable behavior on all compilers.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Arnd Bergmann   authored and   Greg Kroah-Hartman   commited 2020-01-17 19:46:55 +01:00
81f7503fb4
bpf: Clear skb->tstamp in bpf_redirect when necessary
[ Upstream commit 5133498f4ad1123a5ffd4c08df6431dab882cc32 ]

Redirecting a packet from ingress to egress by using bpf_redirect
breaks if the egress interface has an fq qdisc installed. This is the same
problem as fixed in 'commit 8203e2d844d3 ("net: clear skb->tstamp in forwarding paths")

Clear skb->tstamp when redirecting into the egress path.

Fixes: 80b14dee2b ("net: Add a new socket option for a future transmit time.")
Fixes: fb420d5d91c1 ("tcp/fq: move back to CLOCK_MONOTONIC")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/bpf/20191213180817.2510-1-lmb@cloudflare.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

Lorenz Bauer   authored and   Greg Kroah-Hartman   commited 2020-01-12 12:17:15 +01:00
e3d5f12b31
net: add annotations on hh->hh_len lockless accesses
[ Upstream commit c305c6ae79e2ce20c22660ceda94f0d86d639a82 ]

KCSAN reported a data-race [1]

While we can use READ_ONCE() on the read sides,
we need to make sure hh->hh_len is written last.

[1]

BUG: KCSAN: data-race in eth_header_cache / neigh_resolve_output

write to 0xffff8880b9dedcb8 of 4 bytes by task 29760 on cpu 0:
 eth_header_cache+0xa9/0xd0 net/ethernet/eth.c:247
 neigh_hh_init net/core/neighbour.c:1463 [inline]
 neigh_resolve_output net/core/neighbour.c:1480 [inline]
 neigh_resolve_output+0x415/0x470 net/core/neighbour.c:1470
 neigh_output include/net/neighbour.h:511 [inline]
 ip6_finish_output2+0x7a2/0xec0 net/ipv6/ip6_output.c:116
 __ip6_finish_output net/ipv6/ip6_output.c:142 [inline]
 __ip6_finish_output+0x2d7/0x330 net/ipv6/ip6_output.c:127
 ip6_finish_output+0x41/0x160 net/ipv6/ip6_output.c:152
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip6_output+0xf2/0x280 net/ipv6/ip6_output.c:175
 dst_output include/net/dst.h:436 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ndisc_send_skb+0x459/0x5f0 net/ipv6/ndisc.c:505
 ndisc_send_ns+0x207/0x430 net/ipv6/ndisc.c:647
 rt6_probe_deferred+0x98/0xf0 net/ipv6/route.c:615
 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
 worker_thread+0xa0/0x800 kernel/workqueue.c:2415
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

read to 0xffff8880b9dedcb8 of 4 bytes by task 29572 on cpu 1:
 neigh_resolve_output net/core/neighbour.c:1479 [inline]
 neigh_resolve_output+0x113/0x470 net/core/neighbour.c:1470
 neigh_output include/net/neighbour.h:511 [inline]
 ip6_finish_output2+0x7a2/0xec0 net/ipv6/ip6_output.c:116
 __ip6_finish_output net/ipv6/ip6_output.c:142 [inline]
 __ip6_finish_output+0x2d7/0x330 net/ipv6/ip6_output.c:127
 ip6_finish_output+0x41/0x160 net/ipv6/ip6_output.c:152
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip6_output+0xf2/0x280 net/ipv6/ip6_output.c:175
 dst_output include/net/dst.h:436 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ndisc_send_skb+0x459/0x5f0 net/ipv6/ndisc.c:505
 ndisc_send_ns+0x207/0x430 net/ipv6/ndisc.c:647
 rt6_probe_deferred+0x98/0xf0 net/ipv6/route.c:615
 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
 worker_thread+0xa0/0x800 kernel/workqueue.c:2415
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 29572 Comm: kworker/1:4 Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events rt6_probe_deferred

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Eric Dumazet   authored and   Greg Kroah-Hartman   commited 2020-01-09 10:19:09 +01:00
bc5fc4a609
net: core: limit nested device depth
[ Upstream commit 5343da4c17429efaa5fb1594ea96aee1a283e694 ]

Current code doesn't limit the number of nested devices.
Nested devices would be handled recursively and this needs huge stack
memory. So, unlimited nested devices could make stack overflow.

This patch adds upper_level and lower_level, they are common variables
and represent maximum lower/upper depth.
When upper/lower device is attached or dettached,
{lower/upper}_level are updated. and if maximum depth is bigger than 8,
attach routine fails and returns -EMLINK.

In addition, this patch converts recursive routine of
netdev_walk_all_{lower/upper} to iterator routine.

Test commands:
    ip link add dummy0 type dummy
    ip link add link dummy0 name vlan1 type vlan id 1
    ip link set vlan1 up

    for i in {2..55}
    do
	    let A=$i-1

	    ip link add vlan$i link vlan$A type vlan id $i
    done
    ip link del dummy0

Splat looks like:
[  155.513226][  T908] BUG: KASAN: use-after-free in __unwind_start+0x71/0x850
[  155.514162][  T908] Write of size 88 at addr ffff8880608a6cc0 by task ip/908
[  155.515048][  T908]
[  155.515333][  T908] CPU: 0 PID: 908 Comm: ip Not tainted 5.4.0-rc3+ #96
[  155.516147][  T908] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  155.517233][  T908] Call Trace:
[  155.517627][  T908]
[  155.517918][  T908] Allocated by task 0:
[  155.518412][  T908] (stack is not available)
[  155.518955][  T908]
[  155.519228][  T908] Freed by task 0:
[  155.519885][  T908] (stack is not available)
[  155.520452][  T908]
[  155.520729][  T908] The buggy address belongs to the object at ffff8880608a6ac0
[  155.520729][  T908]  which belongs to the cache names_cache of size 4096
[  155.522387][  T908] The buggy address is located 512 bytes inside of
[  155.522387][  T908]  4096-byte region [ffff8880608a6ac0, ffff8880608a7ac0)
[  155.523920][  T908] The buggy address belongs to the page:
[  155.524552][  T908] page:ffffea0001822800 refcount:1 mapcount:0 mapping:ffff88806c657cc0 index:0x0 compound_mapcount:0
[  155.525836][  T908] flags: 0x100000000010200(slab|head)
[  155.526445][  T908] raw: 0100000000010200 ffffea0001813808 ffffea0001a26c08 ffff88806c657cc0
[  155.527424][  T908] raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
[  155.528429][  T908] page dumped because: kasan: bad access detected
[  155.529158][  T908]
[  155.529410][  T908] Memory state around the buggy address:
[  155.530060][  T908]  ffff8880608a6b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  155.530971][  T908]  ffff8880608a6c00: fb fb fb fb fb f1 f1 f1 f1 00 f2 f2 f2 f3 f3 f3
[  155.531889][  T908] >ffff8880608a6c80: f3 fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  155.532806][  T908]                                            ^
[  155.533509][  T908]  ffff8880608a6d00: fb fb fb fb fb fb fb fb fb f1 f1 f1 f1 00 00 00
[  155.534436][  T908]  ffff8880608a6d80: f2 f3 f3 f3 f3 fb fb fb 00 00 00 00 00 00 00 00
[ ... ]

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Taehee Yoo   authored and   Greg Kroah-Hartman   commited 2020-01-09 10:19:09 +01:00
a2e065542a
net, sysctl: Fix compiler warning when only cBPF is present
[ Upstream commit 1148f9adbe71415836a18a36c1b4ece999ab0973 ]

proc_dointvec_minmax_bpf_restricted() has been firstly introduced
in commit 2e4a30983b ("bpf: restrict access to core bpf sysctls")
under CONFIG_HAVE_EBPF_JIT. Then, this ifdef has been removed in
ede95a63b5e8 ("bpf: add bpf_jit_limit knob to restrict unpriv
allocations"), because a new sysctl, bpf_jit_limit, made use of it.
Finally, this parameter has become long instead of integer with
fdadd04931c2 ("bpf: fix bpf_jit_limit knob for PAGE_SIZE >= 64K")
and thus, a new proc_dolongvec_minmax_bpf_restricted() has been
added.

With this last change, we got back to that
proc_dointvec_minmax_bpf_restricted() is used only under
CONFIG_HAVE_EBPF_JIT, but the corresponding ifdef has not been
brought back.

So, in configurations like CONFIG_BPF_JIT=y && CONFIG_HAVE_EBPF_JIT=n
since v4.20 we have:

  CC      net/core/sysctl_net_core.o
net/core/sysctl_net_core.c:292:1: warning: ‘proc_dointvec_minmax_bpf_restricted’ defined but not used [-Wunused-function]
  292 | proc_dointvec_minmax_bpf_restricted(struct ctl_table *table, int write,
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Suppress this by guarding it with CONFIG_HAVE_EBPF_JIT again.

Fixes: fdadd04931c2 ("bpf: fix bpf_jit_limit knob for PAGE_SIZE >= 64K")
Signed-off-by: Alexander Lobakin <alobakin@dlink.ru>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191218091821.7080-1-alobakin@dlink.ru
Signed-off-by: Sasha Levin <sashal@kernel.org>

Alexander Lobakin   authored and   Greg Kroah-Hartman   commited 2020-01-04 19:13:20 +01:00
7fe470885e
net: dsa: fix flow dissection on Tx path
[ Upstream commit 8bef0af09a5415df761b04fa487a6c34acae74bc ]

Commit 43e665287f ("net-next: dsa: fix flow dissection") added an
ability to override protocol and network offset during flow dissection
for DSA-enabled devices (i.e. controllers shipped as switch CPU ports)
in order to fix skb hashing for RPS on Rx path.

However, skb_hash() and added part of code can be invoked not only on
Rx, but also on Tx path if we have a multi-queued device and:
 - kernel is running on UP system or
 - XPS is not configured.

The call stack in this two cases will be like: dev_queue_xmit() ->
__dev_queue_xmit() -> netdev_core_pick_tx() -> netdev_pick_tx() ->
skb_tx_hash() -> skb_get_hash().

The problem is that skbs queued for Tx have both network offset and
correct protocol already set up even after inserting a CPU tag by DSA
tagger, so calling tag_ops->flow_dissect() on this path actually only
breaks flow dissection and hashing.

This can be observed by adding debug prints just before and right after
tag_ops->flow_dissect() call to the related block of code:

Before the patch:

Rx path (RPS):

[   19.240001] Rx: proto: 0x00f8, nhoff: 0	/* ETH_P_XDSA */
[   19.244271] tag_ops->flow_dissect()
[   19.247811] Rx: proto: 0x0800, nhoff: 8	/* ETH_P_IP */

[   19.215435] Rx: proto: 0x00f8, nhoff: 0	/* ETH_P_XDSA */
[   19.219746] tag_ops->flow_dissect()
[   19.223241] Rx: proto: 0x0806, nhoff: 8	/* ETH_P_ARP */

[   18.654057] Rx: proto: 0x00f8, nhoff: 0	/* ETH_P_XDSA */
[   18.658332] tag_ops->flow_dissect()
[   18.661826] Rx: proto: 0x8100, nhoff: 8	/* ETH_P_8021Q */

Tx path (UP system):

[   18.759560] Tx: proto: 0x0800, nhoff: 26	/* ETH_P_IP */
[   18.763933] tag_ops->flow_dissect()
[   18.767485] Tx: proto: 0x920b, nhoff: 34	/* junk */

[   22.800020] Tx: proto: 0x0806, nhoff: 26	/* ETH_P_ARP */
[   22.804392] tag_ops->flow_dissect()
[   22.807921] Tx: proto: 0x920b, nhoff: 34	/* junk */

[   16.898342] Tx: proto: 0x86dd, nhoff: 26	/* ETH_P_IPV6 */
[   16.902705] tag_ops->flow_dissect()
[   16.906227] Tx: proto: 0x920b, nhoff: 34	/* junk */

After:

Rx path (RPS):

[   16.520993] Rx: proto: 0x00f8, nhoff: 0	/* ETH_P_XDSA */
[   16.525260] tag_ops->flow_dissect()
[   16.528808] Rx: proto: 0x0800, nhoff: 8	/* ETH_P_IP */

[   15.484807] Rx: proto: 0x00f8, nhoff: 0	/* ETH_P_XDSA */
[   15.490417] tag_ops->flow_dissect()
[   15.495223] Rx: proto: 0x0806, nhoff: 8	/* ETH_P_ARP */

[   17.134621] Rx: proto: 0x00f8, nhoff: 0	/* ETH_P_XDSA */
[   17.138895] tag_ops->flow_dissect()
[   17.142388] Rx: proto: 0x8100, nhoff: 8	/* ETH_P_8021Q */

Tx path (UP system):

[   15.499558] Tx: proto: 0x0800, nhoff: 26	/* ETH_P_IP */

[   20.664689] Tx: proto: 0x0806, nhoff: 26	/* ETH_P_ARP */

[   18.565782] Tx: proto: 0x86dd, nhoff: 26	/* ETH_P_IPV6 */

In order to fix that we can add the check 'proto == htons(ETH_P_XDSA)'
to prevent code from calling tag_ops->flow_dissect() on Tx.
I also decided to initialize 'offset' variable so tagger callbacks can
now safely leave it untouched without provoking a chaos.

Fixes: 43e665287f ("net-next: dsa: fix flow dissection")
Signed-off-by: Alexander Lobakin <alobakin@dlink.ru>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Alexander Lobakin   authored and   Greg Kroah-Hartman   commited 2019-12-21 10:57:11 +01:00
a7d80e7559
inet: protect against too small mtu values.
[ Upstream commit 501a90c945103e8627406763dac418f20f3837b2 ]

syzbot was once again able to crash a host by setting a very small mtu
on loopback device.

Let's make inetdev_valid_mtu() available in include/net/ip.h,
and use it in ip_setup_cork(), so that we protect both ip_append_page()
and __ip_append_data()

Also add a READ_ONCE() when the device mtu is read.

Pairs this lockless read with one WRITE_ONCE() in __dev_set_mtu(),
even if other code paths might write over this field.

Add a big comment in include/linux/netdevice.h about dev->mtu
needing READ_ONCE()/WRITE_ONCE() annotations.

Hopefully we will add the missing ones in followup patches.

[1]

refcount_t: saturated; leaking memory.
WARNING: CPU: 0 PID: 9464 at lib/refcount.c:22 refcount_warn_saturate+0x138/0x1f0 lib/refcount.c:22
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 9464 Comm: syz-executor850 Not tainted 5.4.0-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+0x197/0x210 lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:221
 __warn.cold+0x2f/0x3e kernel/panic.c:582
 report_bug+0x289/0x300 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 fixup_bug arch/x86/kernel/traps.c:169 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:267
 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:286
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:refcount_warn_saturate+0x138/0x1f0 lib/refcount.c:22
Code: 06 31 ff 89 de e8 c8 f5 e6 fd 84 db 0f 85 6f ff ff ff e8 7b f4 e6 fd 48 c7 c7 e0 71 4f 88 c6 05 56 a6 a4 06 01 e8 c7 a8 b7 fd <0f> 0b e9 50 ff ff ff e8 5c f4 e6 fd 0f b6 1d 3d a6 a4 06 31 ff 89
RSP: 0018:ffff88809689f550 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815e4336 RDI: ffffed1012d13e9c
RBP: ffff88809689f560 R08: ffff88809c50a3c0 R09: fffffbfff15d31b1
R10: fffffbfff15d31b0 R11: ffffffff8ae98d87 R12: 0000000000000001
R13: 0000000000040100 R14: ffff888099041104 R15: ffff888218d96e40
 refcount_add include/linux/refcount.h:193 [inline]
 skb_set_owner_w+0x2b6/0x410 net/core/sock.c:1999
 sock_wmalloc+0xf1/0x120 net/core/sock.c:2096
 ip_append_page+0x7ef/0x1190 net/ipv4/ip_output.c:1383
 udp_sendpage+0x1c7/0x480 net/ipv4/udp.c:1276
 inet_sendpage+0xdb/0x150 net/ipv4/af_inet.c:821
 kernel_sendpage+0x92/0xf0 net/socket.c:3794
 sock_sendpage+0x8b/0xc0 net/socket.c:936
 pipe_to_sendpage+0x2da/0x3c0 fs/splice.c:458
 splice_from_pipe_feed fs/splice.c:512 [inline]
 __splice_from_pipe+0x3ee/0x7c0 fs/splice.c:636
 splice_from_pipe+0x108/0x170 fs/splice.c:671
 generic_splice_sendpage+0x3c/0x50 fs/splice.c:842
 do_splice_from fs/splice.c:861 [inline]
 direct_splice_actor+0x123/0x190 fs/splice.c:1035
 splice_direct_to_actor+0x3b4/0xa30 fs/splice.c:990
 do_splice_direct+0x1da/0x2a0 fs/splice.c:1078
 do_sendfile+0x597/0xd00 fs/read_write.c:1464
 __do_sys_sendfile64 fs/read_write.c:1525 [inline]
 __se_sys_sendfile64 fs/read_write.c:1511 [inline]
 __x64_sys_sendfile64+0x1dd/0x220 fs/read_write.c:1511
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x441409
Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fffb64c4f78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441409
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000005
RBP: 0000000000073b8a R08: 0000000000000010 R09: 0000000000000010
R10: 0000000000010001 R11: 0000000000000246 R12: 0000000000402180
R13: 0000000000402210 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..

Fixes: 1470ddf7f8 ("inet: Remove explicit write references to sk/inet in ip_append_data")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Eric Dumazet   authored and   Greg Kroah-Hartman   commited 2019-12-21 10:57:08 +01:00
d80d67cdaf
net: fix possible overflow in __sk_mem_raise_allocated()
[ Upstream commit 5bf325a53202b8728cf7013b72688c46071e212e ]

With many active TCP sockets, fat TCP sockets could fool
__sk_mem_raise_allocated() thanks to an overflow.

They would increase their share of the memory, instead
of decreasing it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Eric Dumazet   authored and   Greg Kroah-Hartman   commited 2019-12-05 09:21:10 +01:00
d1dde4137a
net/core/neighbour: fix kmemleak minimal reference count for hash tables
[ Upstream commit 01b833ab44c9e484060aad72267fc7e71beb559b ]

This should be 1 for normal allocations, 0 disables leak reporting.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Fixes: 85704cb8dcfd ("net/core/neighbour: tell kmemleak about hash tables")
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Konstantin Khlebnikov   authored and   Greg Kroah-Hartman   commited 2019-12-05 09:21:06 +01:00
91e161b62d