<feed xmlns='http://www.w3.org/2005/Atom'>
<title>BMC/Intel-BMC/linux.git/net/core, branch dev-5.14-intel</title>
<subtitle>Intel OpenBMC Linux kernel source tree (mirror)</subtitle>
<id>https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-5.14-intel</id>
<link rel='self' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-5.14-intel'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/'/>
<updated>2021-10-11T05:22:51+00:00</updated>
<entry>
<title>Merge tag 'v5.14.11' into dev-5.14</title>
<updated>2021-10-11T05:22:51+00:00</updated>
<author>
<name>Joel Stanley</name>
<email>joel@jms.id.au</email>
</author>
<published>2021-10-11T05:22:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=d9563a2fe5e92439bbb1513482702d3eec520de8'/>
<id>urn:sha1:d9563a2fe5e92439bbb1513482702d3eec520de8</id>
<content type='text'>
This is the 5.14.11 stable release

Signed-off-by: Joel Stanley &lt;joel@jms.id.au&gt;
</content>
</entry>
<entry>
<title>af_unix: fix races in sk_peer_pid and sk_peer_cred accesses</title>
<updated>2021-10-07T05:53:16+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2021-09-29T22:57:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=ec716aac7fe4ce85b1ca727ff98a27c01ebde58e'/>
<id>urn:sha1:ec716aac7fe4ce85b1ca727ff98a27c01ebde58e</id>
<content type='text'>
[ Upstream commit 35306eb23814444bd4021f8a1c3047d3cb0c8b2b ]

Jann Horn reported that SO_PEERCRED and SO_PEERGROUPS implementations
are racy, as af_unix can concurrently change sk_peer_pid and sk_peer_cred.

In order to fix this issue, this patch adds a new spinlock that needs
to be used whenever these fields are read or written.

Jann also pointed out that l2cap_sock_get_peer_pid_cb() is currently
reading sk-&gt;sk_peer_pid which makes no sense, as this field
is only possibly set by AF_UNIX sockets.
We will have to clean this in a separate patch.
This could be done by reverting b48596d1dc25 "Bluetooth: L2CAP: Add get_peer_pid callback"
or implementing what was truly expected.

Fixes: 109f6e39fa07 ("af_unix: Allow SO_PEERCRED to work across namespaces.")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: Jann Horn &lt;jannh@google.com&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Cc: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>napi: fix race inside napi_enable</title>
<updated>2021-09-30T08:12:58+00:00</updated>
<author>
<name>Xuan Zhuo</name>
<email>xuanzhuo@linux.alibaba.com</email>
</author>
<published>2021-09-18T08:52:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=ce6c8a9246ad4e6ce957b70efd304bd9c9a3f545'/>
<id>urn:sha1:ce6c8a9246ad4e6ce957b70efd304bd9c9a3f545</id>
<content type='text'>
[ Upstream commit 3765996e4f0b8a755cab215a08df744490c76052 ]

The process will cause napi.state to contain NAPI_STATE_SCHED and
not in the poll_list, which will cause napi_disable() to get stuck.

The prefix "NAPI_STATE_" is removed in the figure below, and
NAPI_STATE_HASHED is ignored in napi.state.

                      CPU0       |                   CPU1       | napi.state
===============================================================================
napi_disable()                   |                              | SCHED | NPSVC
napi_enable()                    |                              |
{                                |                              |
    smp_mb__before_atomic();     |                              |
    clear_bit(SCHED, &amp;n-&gt;state); |                              | NPSVC
                                 | napi_schedule_prep()         | SCHED | NPSVC
                                 | napi_poll()                  |
                                 |   napi_complete_done()       |
                                 |   {                          |
                                 |      if (n-&gt;state &amp; (NPSVC | | (1)
                                 |               _BUSY_POLL)))  |
                                 |           return false;      |
                                 |     ................         |
                                 |   }                          | SCHED | NPSVC
                                 |                              |
    clear_bit(NPSVC, &amp;n-&gt;state); |                              | SCHED
}                                |                              |
                                 |                              |
napi_schedule_prep()             |                              | SCHED | MISSED (2)

(1) Here return direct. Because of NAPI_STATE_NPSVC exists.
(2) NAPI_STATE_SCHED exists. So not add napi.poll_list to sd-&gt;poll_list

Since NAPI_STATE_SCHED already exists and napi is not in the
sd-&gt;poll_list queue, NAPI_STATE_SCHED cannot be cleared and will always
exist.

1. This will cause this queue to no longer receive packets.
2. If you encounter napi_disable under the protection of rtnl_lock, it
   will cause the entire rtnl_lock to be locked, affecting the overall
   system.

This patch uses cmpxchg to implement napi_enable(), which ensures that
there will be no race due to the separation of clear two bits.

Fixes: 2d8bff12699abc ("netpoll: Close race condition between poll_one_napi and napi_disable")
Signed-off-by: Xuan Zhuo &lt;xuanzhuo@linux.alibaba.com&gt;
Reviewed-by: Dust Li &lt;dust.li@linux.alibaba.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'v5.14.6' into dev-5.14</title>
<updated>2021-09-22T00:13:12+00:00</updated>
<author>
<name>Joel Stanley</name>
<email>joel@jms.id.au</email>
</author>
<published>2021-09-22T00:13:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=5fa6722422299ba19d11579cf3cef038f183b80b'/>
<id>urn:sha1:5fa6722422299ba19d11579cf3cef038f183b80b</id>
<content type='text'>
This is the 5.14.6 stable release
</content>
</entry>
<entry>
<title>net: Fix offloading indirect devices dependency on qdisc order creation</title>
<updated>2021-09-18T11:43:53+00:00</updated>
<author>
<name>Eli Cohen</name>
<email>elic@nvidia.com</email>
</author>
<published>2021-08-17T17:05:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=f64c7c47012e3bc2ed71fb76f307c17bb1d43f77'/>
<id>urn:sha1:f64c7c47012e3bc2ed71fb76f307c17bb1d43f77</id>
<content type='text'>
[ Upstream commit 74fc4f828769cca1c3be89ea92cb88feaa27ef52 ]

Currently, when creating an ingress qdisc on an indirect device before
the driver registered for callbacks, the driver will not have a chance
to register its filter configuration callbacks.

To fix that, modify the code such that it keeps track of all the ingress
qdiscs that call flow_indr_dev_setup_offload(). When a driver calls
flow_indr_dev_register(),  go through the list of tracked ingress qdiscs
and call the driver callback entry point so as to give it a chance to
register its callback.

Reviewed-by: Jiri Pirko &lt;jiri@nvidia.com&gt;
Signed-off-by: Eli Cohen &lt;elic@nvidia.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>flow_dissector: Fix out-of-bounds warnings</title>
<updated>2021-09-18T11:43:42+00:00</updated>
<author>
<name>Gustavo A. R. Silva</name>
<email>gustavoars@kernel.org</email>
</author>
<published>2021-07-26T19:25:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=eb4cb29d48059551933fd65318c8c396f942045e'/>
<id>urn:sha1:eb4cb29d48059551933fd65318c8c396f942045e</id>
<content type='text'>
[ Upstream commit 323e0cb473e2a8706ff162b6b4f4fa16023c9ba7 ]

Fix the following out-of-bounds warnings:

    net/core/flow_dissector.c: In function '__skb_flow_dissect':
&gt;&gt; net/core/flow_dissector.c:1104:4: warning: 'memcpy' offset [24, 39] from the object at '&lt;unknown&gt;' is out of the bounds of referenced subobject 'saddr' with type 'struct in6_addr' at offset 8 [-Warray-bounds]
     1104 |    memcpy(&amp;key_addrs-&gt;v6addrs, &amp;iph-&gt;saddr,
          |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     1105 |           sizeof(key_addrs-&gt;v6addrs));
          |           ~~~~~~~~~~~~~~~~~~~~~~~~~~~
    In file included from include/linux/ipv6.h:5,
                     from net/core/flow_dissector.c:6:
    include/uapi/linux/ipv6.h:133:18: note: subobject 'saddr' declared here
      133 |  struct in6_addr saddr;
          |                  ^~~~~
&gt;&gt; net/core/flow_dissector.c:1059:4: warning: 'memcpy' offset [16, 19] from the object at '&lt;unknown&gt;' is out of the bounds of referenced subobject 'saddr' with type 'unsigned int' at offset 12 [-Warray-bounds]
     1059 |    memcpy(&amp;key_addrs-&gt;v4addrs, &amp;iph-&gt;saddr,
          |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     1060 |           sizeof(key_addrs-&gt;v4addrs));
          |           ~~~~~~~~~~~~~~~~~~~~~~~~~~~
    In file included from include/linux/ip.h:17,
                     from net/core/flow_dissector.c:5:
    include/uapi/linux/ip.h:103:9: note: subobject 'saddr' declared here
      103 |  __be32 saddr;
          |         ^~~~~

The problem is that the original code is trying to copy data into a
couple of struct members adjacent to each other in a single call to
memcpy().  So, the compiler legitimately complains about it. As these
are just a couple of members, fix this by copying each one of them in
separate calls to memcpy().

This helps with the ongoing efforts to globally enable -Warray-bounds
and get us closer to being able to tighten the FORTIFY_SOURCE routines
on memcpy().

Link: https://github.com/KSPP/linux/issues/109
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Link: https://lore.kernel.org/lkml/d5ae2e65-1f18-2577-246f-bada7eee6ccd@intel.com/
Signed-off-by: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>devlink: Break parameter notification sequence to be before/after unload/load driver</title>
<updated>2021-09-15T08:02:36+00:00</updated>
<author>
<name>Leon Romanovsky</name>
<email>leonro@nvidia.com</email>
</author>
<published>2021-07-29T17:19:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=ea003ac946386cde7d894ed274ecc41b36026878'/>
<id>urn:sha1:ea003ac946386cde7d894ed274ecc41b36026878</id>
<content type='text'>
commit 05a7f4a8dff19999ca8a83a35ff4782689de7bfc upstream.

The change of namespaces during devlink reload calls to driver unload
before it accesses devlink parameters. The commands below causes to
use-after-free bug when trying to get flow steering mode.

 * ip netns add n1
 * devlink dev reload pci/0000:00:09.0 netns n1

 ==================================================================
 BUG: KASAN: use-after-free in mlx5_devlink_fs_mode_get+0x96/0xa0 [mlx5_core]
 Read of size 4 at addr ffff888009d04308 by task devlink/275

 CPU: 6 PID: 275 Comm: devlink Not tainted 5.12.0-rc2+ #2853
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
 Call Trace:
  dump_stack+0x93/0xc2
  print_address_description.constprop.0+0x18/0x140
  ? mlx5_devlink_fs_mode_get+0x96/0xa0 [mlx5_core]
  ? mlx5_devlink_fs_mode_get+0x96/0xa0 [mlx5_core]
  kasan_report.cold+0x7c/0xd8
  ? mlx5_devlink_fs_mode_get+0x96/0xa0 [mlx5_core]
  mlx5_devlink_fs_mode_get+0x96/0xa0 [mlx5_core]
  devlink_nl_param_fill+0x1c8/0xe80
  ? __free_pages_ok+0x37a/0x8a0
  ? devlink_flash_update_timeout_notify+0xd0/0xd0
  ? lock_acquire+0x1a9/0x6d0
  ? fs_reclaim_acquire+0xb7/0x160
  ? lock_is_held_type+0x98/0x110
  ? 0xffffffff81000000
  ? lock_release+0x1f9/0x6c0
  ? fs_reclaim_release+0xa1/0xf0
  ? lock_downgrade+0x6d0/0x6d0
  ? lock_is_held_type+0x98/0x110
  ? lock_is_held_type+0x98/0x110
  ? memset+0x20/0x40
  ? __build_skb_around+0x1f8/0x2b0
  devlink_param_notify+0x6d/0x180
  devlink_reload+0x1c3/0x520
  ? devlink_remote_reload_actions_performed+0x30/0x30
  ? mutex_trylock+0x24b/0x2d0
  ? devlink_nl_cmd_reload+0x62b/0x1070
  devlink_nl_cmd_reload+0x66d/0x1070
  ? devlink_reload+0x520/0x520
  ? devlink_get_from_attrs+0x1bc/0x260
  ? devlink_nl_pre_doit+0x64/0x4d0
  genl_family_rcv_msg_doit+0x1e9/0x2f0
  ? mutex_lock_io_nested+0x1130/0x1130
  ? genl_family_rcv_msg_attrs_parse.constprop.0+0x240/0x240
  ? security_capable+0x51/0x90
  genl_rcv_msg+0x27f/0x4a0
  ? genl_get_cmd+0x3c0/0x3c0
  ? lock_acquire+0x1a9/0x6d0
  ? devlink_reload+0x520/0x520
  ? lock_release+0x6c0/0x6c0
  netlink_rcv_skb+0x11d/0x340
  ? genl_get_cmd+0x3c0/0x3c0
  ? netlink_ack+0x9f0/0x9f0
  ? lock_release+0x1f9/0x6c0
  genl_rcv+0x24/0x40
  netlink_unicast+0x433/0x700
  ? netlink_attachskb+0x730/0x730
  ? _copy_from_iter_full+0x178/0x650
  ? __alloc_skb+0x113/0x2b0
  netlink_sendmsg+0x6f1/0xbd0
  ? netlink_unicast+0x700/0x700
  ? lock_is_held_type+0x98/0x110
  ? netlink_unicast+0x700/0x700
  sock_sendmsg+0xb0/0xe0
  __sys_sendto+0x193/0x240
  ? __x64_sys_getpeername+0xb0/0xb0
  ? do_sys_openat2+0x10b/0x370
  ? __up_read+0x1a1/0x7b0
  ? do_user_addr_fault+0x219/0xdc0
  ? __x64_sys_openat+0x120/0x1d0
  ? __x64_sys_open+0x1a0/0x1a0
  __x64_sys_sendto+0xdd/0x1b0
  ? syscall_enter_from_user_mode+0x1d/0x50
  do_syscall_64+0x2d/0x40
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7fc69d0af14a
 Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 2c 00 00 00 0f 05 &lt;48&gt; 3d 00 f0 ff ff 77 76 c3 0f 1f 44 00 00 55 48 83 ec 30 44 89 4c
 RSP: 002b:00007ffc1d8292f8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fc69d0af14a
 RDX: 0000000000000038 RSI: 0000555f57c56440 RDI: 0000000000000003
 RBP: 0000555f57c56410 R08: 00007fc69d17b200 R09: 000000000000000c
 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

 Allocated by task 146:
  kasan_save_stack+0x1b/0x40
  __kasan_kmalloc+0x99/0xc0
  mlx5_init_fs+0xf0/0x1c50 [mlx5_core]
  mlx5_load+0xd2/0x180 [mlx5_core]
  mlx5_init_one+0x2f6/0x450 [mlx5_core]
  probe_one+0x47d/0x6e0 [mlx5_core]
  pci_device_probe+0x2a0/0x4a0
  really_probe+0x20a/0xc90
  driver_probe_device+0xd8/0x380
  device_driver_attach+0x1df/0x250
  __driver_attach+0xff/0x240
  bus_for_each_dev+0x11e/0x1a0
  bus_add_driver+0x309/0x570
  driver_register+0x1ee/0x380
  0xffffffffa06b8062
  do_one_initcall+0xd5/0x410
  do_init_module+0x1c8/0x760
  load_module+0x6d8b/0x9650
  __do_sys_finit_module+0x118/0x1b0
  do_syscall_64+0x2d/0x40
  entry_SYSCALL_64_after_hwframe+0x44/0xae

 Freed by task 275:
  kasan_save_stack+0x1b/0x40
  kasan_set_track+0x1c/0x30
  kasan_set_free_info+0x20/0x30
  __kasan_slab_free+0x102/0x140
  slab_free_freelist_hook+0x74/0x1b0
  kfree+0xd7/0x2a0
  mlx5_unload+0x16/0xb0 [mlx5_core]
  mlx5_unload_one+0xae/0x120 [mlx5_core]
  mlx5_devlink_reload_down+0x1bc/0x380 [mlx5_core]
  devlink_reload+0x141/0x520
  devlink_nl_cmd_reload+0x66d/0x1070
  genl_family_rcv_msg_doit+0x1e9/0x2f0
  genl_rcv_msg+0x27f/0x4a0
  netlink_rcv_skb+0x11d/0x340
  genl_rcv+0x24/0x40
  netlink_unicast+0x433/0x700
  netlink_sendmsg+0x6f1/0xbd0
  sock_sendmsg+0xb0/0xe0
  __sys_sendto+0x193/0x240
  __x64_sys_sendto+0xdd/0x1b0
  do_syscall_64+0x2d/0x40
  entry_SYSCALL_64_after_hwframe+0x44/0xae

 The buggy address belongs to the object at ffff888009d04300
  which belongs to the cache kmalloc-128 of size 128
 The buggy address is located 8 bytes inside of
  128-byte region [ffff888009d04300, ffff888009d04380)
 The buggy address belongs to the page:
 page:0000000086a64ecc refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888009d04000 pfn:0x9d04
 head:0000000086a64ecc order:1 compound_mapcount:0
 flags: 0x4000000000010200(slab|head)
 raw: 4000000000010200 ffffea0000203980 0000000200000002 ffff8880050428c0
 raw: ffff888009d04000 000000008020001d 00000001ffffffff 0000000000000000
 page dumped because: kasan: bad access detected

 Memory state around the buggy address:
  ffff888009d04200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff888009d04280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 &gt;ffff888009d04300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                       ^
  ffff888009d04380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
  ffff888009d04400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ==================================================================

The right solution to devlink reload is to notify about deletion of
parameters, unload driver, change net namespaces, load driver and notify
about addition of parameters.

Fixes: 070c63f20f6c ("net: devlink: allow to change namespaces during reload")
Reviewed-by: Parav Pandit &lt;parav@nvidia.com&gt;
Signed-off-by: Leon Romanovsky &lt;leonro@nvidia.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>devlink: Clear whole devlink_flash_notify struct</title>
<updated>2021-09-15T08:02:23+00:00</updated>
<author>
<name>Leon Romanovsky</name>
<email>leonro@nvidia.com</email>
</author>
<published>2021-08-14T09:57:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=5eb9d59b73f6ec20f939daa4939bbbe5eaf1e8e3'/>
<id>urn:sha1:5eb9d59b73f6ec20f939daa4939bbbe5eaf1e8e3</id>
<content type='text'>
[ Upstream commit ed43fbac717882165a2a4bd64f7b1f56f7467bb7 ]

The { 0 } doesn't clear all fields in the struct, but tells to the
compiler to set all fields to zero and doesn't touch any sub-fields
if they exists.

The {} is an empty initialiser that instructs to fully initialize whole
struct including sub-fields, which is error-prone for future
devlink_flash_notify extensions.

Fixes: 6700acc5f1fe ("devlink: collect flash notify params into a struct")
Signed-off-by: Leon Romanovsky &lt;leonro@nvidia.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>mctp: Add MCTP base</title>
<updated>2021-09-02T05:51:45+00:00</updated>
<author>
<name>Jeremy Kerr</name>
<email>jk@codeconstruct.com.au</email>
</author>
<published>2021-07-29T02:20:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=400ac96b99f4e7d6abd4516552ad91a9e2d17689'/>
<id>urn:sha1:400ac96b99f4e7d6abd4516552ad91a9e2d17689</id>
<content type='text'>
Add basic Kconfig, an initial (empty) af_mctp source object, and
{AF,PF}_MCTP definitions, and the required definitions for a new
protocol type.

Signed-off-by: Jeremy Kerr &lt;jk@codeconstruct.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>rtnetlink: Return correct error on changing device netns</title>
<updated>2021-08-26T11:08:08+00:00</updated>
<author>
<name>Andrey Ignatov</name>
<email>rdna@fb.com</email>
</author>
<published>2021-08-26T00:25:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=96a6b93b69880b2c978e1b2be9cae6970b605008'/>
<id>urn:sha1:96a6b93b69880b2c978e1b2be9cae6970b605008</id>
<content type='text'>
Currently when device is moved between network namespaces using
RTM_NEWLINK message type and one of netns attributes (FLA_NET_NS_PID,
IFLA_NET_NS_FD, IFLA_TARGET_NETNSID) but w/o specifying IFLA_IFNAME, and
target namespace already has device with same name, userspace will get
EINVAL what is confusing and makes debugging harder.

Fix it so that userspace gets more appropriate EEXIST instead what makes
debugging much easier.

Before:

  # ./ifname.sh
  + ip netns add ns0
  + ip netns exec ns0 ip link add l0 type dummy
  + ip netns exec ns0 ip link show l0
  8: l0: &lt;BROADCAST,NOARP&gt; mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether 66:90:b5:d5:78:69 brd ff:ff:ff:ff:ff:ff
  + ip link add l0 type dummy
  + ip link show l0
  10: l0: &lt;BROADCAST,NOARP&gt; mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether 6e:c6:1f:15:20:8d brd ff:ff:ff:ff:ff:ff
  + ip link set l0 netns ns0
  RTNETLINK answers: Invalid argument

After:

  # ./ifname.sh
  + ip netns add ns0
  + ip netns exec ns0 ip link add l0 type dummy
  + ip netns exec ns0 ip link show l0
  8: l0: &lt;BROADCAST,NOARP&gt; mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether 1e:4a:72:e3:e3:8f brd ff:ff:ff:ff:ff:ff
  + ip link add l0 type dummy
  + ip link show l0
  10: l0: &lt;BROADCAST,NOARP&gt; mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether f2:fc:fe:2b:7d:a6 brd ff:ff:ff:ff:ff:ff
  + ip link set l0 netns ns0
  RTNETLINK answers: File exists

The problem is that do_setlink() passes its `char *ifname` argument,
that it gets from a caller, to __dev_change_net_namespace() as is (as
`const char *pat`), but semantics of ifname and pat can be different.

For example, __rtnl_newlink() does this:

net/core/rtnetlink.c
    3270	char ifname[IFNAMSIZ];
     ...
    3286	if (tb[IFLA_IFNAME])
    3287		nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
    3288	else
    3289		ifname[0] = '\0';
     ...
    3364	if (dev) {
     ...
    3394		return do_setlink(skb, dev, ifm, extack, tb, ifname, status);
    3395	}

, i.e. do_setlink() gets ifname pointer that is always valid no matter
if user specified IFLA_IFNAME or not and then do_setlink() passes this
ifname pointer as is to __dev_change_net_namespace() as pat argument.

But the pat (pattern) in __dev_change_net_namespace() is used as:

net/core/dev.c
   11198	err = -EEXIST;
   11199	if (__dev_get_by_name(net, dev-&gt;name)) {
   11200		/* We get here if we can't use the current device name */
   11201		if (!pat)
   11202			goto out;
   11203		err = dev_get_valid_name(net, dev, pat);
   11204		if (err &lt; 0)
   11205			goto out;
   11206	}

As the result the `goto out` path on line 11202 is neven taken and
instead of returning EEXIST defined on line 11198,
__dev_change_net_namespace() returns an error from dev_get_valid_name()
and this, in turn, will be EINVAL for ifname[0] = '\0' set earlier.

Fixes: d8a5ec672768 ("[NET]: netlink support for moving devices between network namespaces.")
Signed-off-by: Andrey Ignatov &lt;rdna@fb.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
</feed>
