<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/core/net_namespace.c, branch linux-5.4.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>net: add exit_batch_rtnl() method</title>
<updated>2025-02-01T17:18:49+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2024-02-06T14:42:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2131315571026a91ecda9a690f68bf1de0f51ccd'/>
<id>2131315571026a91ecda9a690f68bf1de0f51ccd</id>
<content type='text'>
[ Upstream commit fd4f101edbd9f99567ab2adb1f2169579ede7c13 ]

Many (struct pernet_operations)-&gt;exit_batch() methods have
to acquire rtnl.

In presence of rtnl mutex pressure, this makes cleanup_net()
very slow.

This patch adds a new exit_batch_rtnl() method to reduce
number of rtnl acquisitions from cleanup_net().

exit_batch_rtnl() handlers are called while rtnl is locked,
and devices to be killed can be queued in a list provided
as their second argument.

A single unregister_netdevice_many() is called right
before rtnl is released.

exit_batch_rtnl() handlers are called before -&gt;exit() and
-&gt;exit_batch() handlers.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Antoine Tenart &lt;atenart@kernel.org&gt;
Link: https://lore.kernel.org/r/20240206144313.2050392-2-edumazet@google.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Stable-dep-of: 46841c7053e6 ("gtp: Use for_each_netdev_rcu() in gtp_genl_dump_pdp().")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit fd4f101edbd9f99567ab2adb1f2169579ede7c13 ]

Many (struct pernet_operations)-&gt;exit_batch() methods have
to acquire rtnl.

In presence of rtnl mutex pressure, this makes cleanup_net()
very slow.

This patch adds a new exit_batch_rtnl() method to reduce
number of rtnl acquisitions from cleanup_net().

exit_batch_rtnl() handlers are called while rtnl is locked,
and devices to be killed can be queued in a list provided
as their second argument.

A single unregister_netdevice_many() is called right
before rtnl is released.

exit_batch_rtnl() handlers are called before -&gt;exit() and
-&gt;exit_batch() handlers.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Antoine Tenart &lt;atenart@kernel.org&gt;
Link: https://lore.kernel.org/r/20240206144313.2050392-2-edumazet@google.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Stable-dep-of: 46841c7053e6 ("gtp: Use for_each_netdev_rcu() in gtp_genl_dump_pdp().")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: net_namespace: Optimize the code</title>
<updated>2025-02-01T17:18:49+00:00</updated>
<author>
<name>Yajun Deng</name>
<email>yajun.deng@linux.dev</email>
</author>
<published>2021-08-17T15:23:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=378b81b092351ffa99284a807615d9d8f4b83df7'/>
<id>378b81b092351ffa99284a807615d9d8f4b83df7</id>
<content type='text'>
[ Upstream commit 41467d2ff4dfe1837cbb0f45e2088e6e787580c6 ]

There is only one caller for ops_free(), so inline it.
Separate net_drop_ns() and net_free(), so the net_free()
can be called directly.
Add free_exit_list() helper function for free net_exit_list.

====================
v2:
 - v1 does not apply, rebase it.
====================

Signed-off-by: Yajun Deng &lt;yajun.deng@linux.dev&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Stable-dep-of: 46841c7053e6 ("gtp: Use for_each_netdev_rcu() in gtp_genl_dump_pdp().")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 41467d2ff4dfe1837cbb0f45e2088e6e787580c6 ]

There is only one caller for ops_free(), so inline it.
Separate net_drop_ns() and net_free(), so the net_free()
can be called directly.
Add free_exit_list() helper function for free net_exit_list.

====================
v2:
 - v1 does not apply, rebase it.
====================

Signed-off-by: Yajun Deng &lt;yajun.deng@linux.dev&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Stable-dep-of: 46841c7053e6 ("gtp: Use for_each_netdev_rcu() in gtp_genl_dump_pdp().")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netns: Make get_net_ns() handle zero refcount net</title>
<updated>2024-07-05T07:08:23+00:00</updated>
<author>
<name>Yue Haibing</name>
<email>yuehaibing@huawei.com</email>
</author>
<published>2024-06-14T13:13:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3a6cd326ead7c8bb1f64486789a01974a9f1ad55'/>
<id>3a6cd326ead7c8bb1f64486789a01974a9f1ad55</id>
<content type='text'>
[ Upstream commit ff960f9d3edbe08a736b5a224d91a305ccc946b0 ]

Syzkaller hit a warning:
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 3 PID: 7890 at lib/refcount.c:25 refcount_warn_saturate+0xdf/0x1d0
Modules linked in:
CPU: 3 PID: 7890 Comm: tun Not tainted 6.10.0-rc3-00100-gcaa4f9578aba-dirty #310
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
RIP: 0010:refcount_warn_saturate+0xdf/0x1d0
Code: 41 49 04 31 ff 89 de e8 9f 1e cd fe 84 db 75 9c e8 76 26 cd fe c6 05 b6 41 49 04 01 90 48 c7 c7 b8 8e 25 86 e8 d2 05 b5 fe 90 &lt;0f&gt; 0b 90 90 e9 79 ff ff ff e8 53 26 cd fe 0f b6 1
RSP: 0018:ffff8881067b7da0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff811c72ac
RDX: ffff8881026a2140 RSI: ffffffff811c72b5 RDI: 0000000000000001
RBP: ffff8881067b7db0 R08: 0000000000000000 R09: 205b5d3730353139
R10: 0000000000000000 R11: 205d303938375420 R12: ffff8881086500c4
R13: ffff8881086500c4 R14: ffff8881086500b0 R15: ffff888108650040
FS:  00007f5b2961a4c0(0000) GS:ffff88823bd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d7ed36fd18 CR3: 00000001482f6000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 &lt;TASK&gt;
 ? show_regs+0xa3/0xc0
 ? __warn+0xa5/0x1c0
 ? refcount_warn_saturate+0xdf/0x1d0
 ? report_bug+0x1fc/0x2d0
 ? refcount_warn_saturate+0xdf/0x1d0
 ? handle_bug+0xa1/0x110
 ? exc_invalid_op+0x3c/0xb0
 ? asm_exc_invalid_op+0x1f/0x30
 ? __warn_printk+0xcc/0x140
 ? __warn_printk+0xd5/0x140
 ? refcount_warn_saturate+0xdf/0x1d0
 get_net_ns+0xa4/0xc0
 ? __pfx_get_net_ns+0x10/0x10
 open_related_ns+0x5a/0x130
 __tun_chr_ioctl+0x1616/0x2370
 ? __sanitizer_cov_trace_switch+0x58/0xa0
 ? __sanitizer_cov_trace_const_cmp2+0x1c/0x30
 ? __pfx_tun_chr_ioctl+0x10/0x10
 tun_chr_ioctl+0x2f/0x40
 __x64_sys_ioctl+0x11b/0x160
 x64_sys_call+0x1211/0x20d0
 do_syscall_64+0x9e/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5b28f165d7
Code: b3 66 90 48 8b 05 b1 48 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 8b 0d 81 48 2d 00 8
RSP: 002b:00007ffc2b59c5e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5b28f165d7
RDX: 0000000000000000 RSI: 00000000000054e3 RDI: 0000000000000003
RBP: 00007ffc2b59c650 R08: 00007f5b291ed8c0 R09: 00007f5b2961a4c0
R10: 0000000029690010 R11: 0000000000000246 R12: 0000000000400730
R13: 00007ffc2b59cf40 R14: 0000000000000000 R15: 0000000000000000
 &lt;/TASK&gt;
Kernel panic - not syncing: kernel: panic_on_warn set ...

This is trigger as below:
          ns0                                    ns1
tun_set_iff() //dev is tun0
   tun-&gt;dev = dev
//ip link set tun0 netns ns1
                                       put_net() //ref is 0
__tun_chr_ioctl() //TUNGETDEVNETNS
   net = dev_net(tun-&gt;dev);
   open_related_ns(&amp;net-&gt;ns, get_net_ns); //ns1
     get_net_ns()
        get_net() //addition on 0

Use maybe_get_net() in get_net_ns in case net's ref is zero to fix this

Fixes: 0c3e0e3bb623 ("tun: Add ioctl() TUNGETDEVNETNS cmd to allow obtaining real net ns of tun device")
Signed-off-by: Yue Haibing &lt;yuehaibing@huawei.com&gt;
Link: https://lore.kernel.org/r/20240614131302.2698509-1-yuehaibing@huawei.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit ff960f9d3edbe08a736b5a224d91a305ccc946b0 ]

Syzkaller hit a warning:
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 3 PID: 7890 at lib/refcount.c:25 refcount_warn_saturate+0xdf/0x1d0
Modules linked in:
CPU: 3 PID: 7890 Comm: tun Not tainted 6.10.0-rc3-00100-gcaa4f9578aba-dirty #310
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
RIP: 0010:refcount_warn_saturate+0xdf/0x1d0
Code: 41 49 04 31 ff 89 de e8 9f 1e cd fe 84 db 75 9c e8 76 26 cd fe c6 05 b6 41 49 04 01 90 48 c7 c7 b8 8e 25 86 e8 d2 05 b5 fe 90 &lt;0f&gt; 0b 90 90 e9 79 ff ff ff e8 53 26 cd fe 0f b6 1
RSP: 0018:ffff8881067b7da0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff811c72ac
RDX: ffff8881026a2140 RSI: ffffffff811c72b5 RDI: 0000000000000001
RBP: ffff8881067b7db0 R08: 0000000000000000 R09: 205b5d3730353139
R10: 0000000000000000 R11: 205d303938375420 R12: ffff8881086500c4
R13: ffff8881086500c4 R14: ffff8881086500b0 R15: ffff888108650040
FS:  00007f5b2961a4c0(0000) GS:ffff88823bd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d7ed36fd18 CR3: 00000001482f6000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 &lt;TASK&gt;
 ? show_regs+0xa3/0xc0
 ? __warn+0xa5/0x1c0
 ? refcount_warn_saturate+0xdf/0x1d0
 ? report_bug+0x1fc/0x2d0
 ? refcount_warn_saturate+0xdf/0x1d0
 ? handle_bug+0xa1/0x110
 ? exc_invalid_op+0x3c/0xb0
 ? asm_exc_invalid_op+0x1f/0x30
 ? __warn_printk+0xcc/0x140
 ? __warn_printk+0xd5/0x140
 ? refcount_warn_saturate+0xdf/0x1d0
 get_net_ns+0xa4/0xc0
 ? __pfx_get_net_ns+0x10/0x10
 open_related_ns+0x5a/0x130
 __tun_chr_ioctl+0x1616/0x2370
 ? __sanitizer_cov_trace_switch+0x58/0xa0
 ? __sanitizer_cov_trace_const_cmp2+0x1c/0x30
 ? __pfx_tun_chr_ioctl+0x10/0x10
 tun_chr_ioctl+0x2f/0x40
 __x64_sys_ioctl+0x11b/0x160
 x64_sys_call+0x1211/0x20d0
 do_syscall_64+0x9e/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5b28f165d7
Code: b3 66 90 48 8b 05 b1 48 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 8b 0d 81 48 2d 00 8
RSP: 002b:00007ffc2b59c5e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5b28f165d7
RDX: 0000000000000000 RSI: 00000000000054e3 RDI: 0000000000000003
RBP: 00007ffc2b59c650 R08: 00007f5b291ed8c0 R09: 00007f5b2961a4c0
R10: 0000000029690010 R11: 0000000000000246 R12: 0000000000400730
R13: 00007ffc2b59cf40 R14: 0000000000000000 R15: 0000000000000000
 &lt;/TASK&gt;
Kernel panic - not syncing: kernel: panic_on_warn set ...

This is trigger as below:
          ns0                                    ns1
tun_set_iff() //dev is tun0
   tun-&gt;dev = dev
//ip link set tun0 netns ns1
                                       put_net() //ref is 0
__tun_chr_ioctl() //TUNGETDEVNETNS
   net = dev_net(tun-&gt;dev);
   open_related_ns(&amp;net-&gt;ns, get_net_ns); //ns1
     get_net_ns()
        get_net() //addition on 0

Use maybe_get_net() in get_net_ns in case net's ref is zero to fix this

Fixes: 0c3e0e3bb623 ("tun: Add ioctl() TUNGETDEVNETNS cmd to allow obtaining real net ns of tun device")
Signed-off-by: Yue Haibing &lt;yuehaibing@huawei.com&gt;
Link: https://lore.kernel.org/r/20240614131302.2698509-1-yuehaibing@huawei.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: fix out-of-bounds access in ops_init</title>
<updated>2024-05-17T09:43:55+00:00</updated>
<author>
<name>Thadeu Lima de Souza Cascardo</name>
<email>cascardo@igalia.com</email>
</author>
<published>2024-05-02T13:20:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7b0e64583eab8c1d896b47e5dd0bf2e7d86ec41f'/>
<id>7b0e64583eab8c1d896b47e5dd0bf2e7d86ec41f</id>
<content type='text'>
commit a26ff37e624d12e28077e5b24d2b264f62764ad6 upstream.

net_alloc_generic is called by net_alloc, which is called without any
locking. It reads max_gen_ptrs, which is changed under pernet_ops_rwsem. It
is read twice, first to allocate an array, then to set s.len, which is
later used to limit the bounds of the array access.

It is possible that the array is allocated and another thread is
registering a new pernet ops, increments max_gen_ptrs, which is then used
to set s.len with a larger than allocated length for the variable array.

Fix it by reading max_gen_ptrs only once in net_alloc_generic. If
max_gen_ptrs is later incremented, it will be caught in net_assign_generic.

Signed-off-by: Thadeu Lima de Souza Cascardo &lt;cascardo@igalia.com&gt;
Fixes: 073862ba5d24 ("netns: fix net_alloc_generic()")
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240502132006.3430840-1-cascardo@igalia.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a26ff37e624d12e28077e5b24d2b264f62764ad6 upstream.

net_alloc_generic is called by net_alloc, which is called without any
locking. It reads max_gen_ptrs, which is changed under pernet_ops_rwsem. It
is read twice, first to allocate an array, then to set s.len, which is
later used to limit the bounds of the array access.

It is possible that the array is allocated and another thread is
registering a new pernet ops, increments max_gen_ptrs, which is then used
to set s.len with a larger than allocated length for the variable array.

Fix it by reading max_gen_ptrs only once in net_alloc_generic. If
max_gen_ptrs is later incremented, it will be caught in net_assign_generic.

Signed-off-by: Thadeu Lima de Souza Cascardo &lt;cascardo@igalia.com&gt;
Fixes: 073862ba5d24 ("netns: fix net_alloc_generic()")
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240502132006.3430840-1-cascardo@igalia.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: fix UaF in netns ops registration error path</title>
<updated>2023-02-06T06:52:45+00:00</updated>
<author>
<name>Paolo Abeni</name>
<email>pabeni@redhat.com</email>
</author>
<published>2023-01-19T18:55:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ddd49cbbd4c1ceb38032018b589b44208e54f55e'/>
<id>ddd49cbbd4c1ceb38032018b589b44208e54f55e</id>
<content type='text'>
[ Upstream commit 71ab9c3e2253619136c31c89dbb2c69305cc89b1 ]

If net_assign_generic() fails, the current error path in ops_init() tries
to clear the gen pointer slot. Anyway, in such error path, the gen pointer
itself has not been modified yet, and the existing and accessed one is
smaller than the accessed index, causing an out-of-bounds error:

 BUG: KASAN: slab-out-of-bounds in ops_init+0x2de/0x320
 Write of size 8 at addr ffff888109124978 by task modprobe/1018

 CPU: 2 PID: 1018 Comm: modprobe Not tainted 6.2.0-rc2.mptcp_ae5ac65fbed5+ #1641
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.1-2.fc37 04/01/2014
 Call Trace:
  &lt;TASK&gt;
  dump_stack_lvl+0x6a/0x9f
  print_address_description.constprop.0+0x86/0x2b5
  print_report+0x11b/0x1fb
  kasan_report+0x87/0xc0
  ops_init+0x2de/0x320
  register_pernet_operations+0x2e4/0x750
  register_pernet_subsys+0x24/0x40
  tcf_register_action+0x9f/0x560
  do_one_initcall+0xf9/0x570
  do_init_module+0x190/0x650
  load_module+0x1fa5/0x23c0
  __do_sys_finit_module+0x10d/0x1b0
  do_syscall_64+0x58/0x80
  entry_SYSCALL_64_after_hwframe+0x72/0xdc
 RIP: 0033:0x7f42518f778d
 Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 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 &lt;48&gt; 3d 01 f0 ff
       ff 73 01 c3 48 8b 0d cb 56 2c 00 f7 d8 64 89 01 48
 RSP: 002b:00007fff96869688 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
 RAX: ffffffffffffffda RBX: 00005568ef7f7c90 RCX: 00007f42518f778d
 RDX: 0000000000000000 RSI: 00005568ef41d796 RDI: 0000000000000003
 RBP: 00005568ef41d796 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000
 R13: 00005568ef7f7d30 R14: 0000000000040000 R15: 0000000000000000
  &lt;/TASK&gt;

This change addresses the issue by skipping the gen pointer
de-reference in the mentioned error-path.

Found by code inspection and verified with explicit error injection
on a kasan-enabled kernel.

Fixes: d266935ac43d ("net: fix UAF issue in nfqnl_nf_hook_drop() when ops_init() failed")
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Reviewed-by: Simon Horman &lt;simon.horman@corigine.com&gt;
Link: https://lore.kernel.org/r/cec4e0f3bb2c77ac03a6154a8508d3930beb5f0f.1674154348.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 71ab9c3e2253619136c31c89dbb2c69305cc89b1 ]

If net_assign_generic() fails, the current error path in ops_init() tries
to clear the gen pointer slot. Anyway, in such error path, the gen pointer
itself has not been modified yet, and the existing and accessed one is
smaller than the accessed index, causing an out-of-bounds error:

 BUG: KASAN: slab-out-of-bounds in ops_init+0x2de/0x320
 Write of size 8 at addr ffff888109124978 by task modprobe/1018

 CPU: 2 PID: 1018 Comm: modprobe Not tainted 6.2.0-rc2.mptcp_ae5ac65fbed5+ #1641
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.1-2.fc37 04/01/2014
 Call Trace:
  &lt;TASK&gt;
  dump_stack_lvl+0x6a/0x9f
  print_address_description.constprop.0+0x86/0x2b5
  print_report+0x11b/0x1fb
  kasan_report+0x87/0xc0
  ops_init+0x2de/0x320
  register_pernet_operations+0x2e4/0x750
  register_pernet_subsys+0x24/0x40
  tcf_register_action+0x9f/0x560
  do_one_initcall+0xf9/0x570
  do_init_module+0x190/0x650
  load_module+0x1fa5/0x23c0
  __do_sys_finit_module+0x10d/0x1b0
  do_syscall_64+0x58/0x80
  entry_SYSCALL_64_after_hwframe+0x72/0xdc
 RIP: 0033:0x7f42518f778d
 Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 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 &lt;48&gt; 3d 01 f0 ff
       ff 73 01 c3 48 8b 0d cb 56 2c 00 f7 d8 64 89 01 48
 RSP: 002b:00007fff96869688 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
 RAX: ffffffffffffffda RBX: 00005568ef7f7c90 RCX: 00007f42518f778d
 RDX: 0000000000000000 RSI: 00005568ef41d796 RDI: 0000000000000003
 RBP: 00005568ef41d796 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000
 R13: 00005568ef7f7d30 R14: 0000000000040000 R15: 0000000000000000
  &lt;/TASK&gt;

This change addresses the issue by skipping the gen pointer
de-reference in the mentioned error-path.

Found by code inspection and verified with explicit error injection
on a kasan-enabled kernel.

Fixes: d266935ac43d ("net: fix UAF issue in nfqnl_nf_hook_drop() when ops_init() failed")
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Reviewed-by: Simon Horman &lt;simon.horman@corigine.com&gt;
Link: https://lore.kernel.org/r/cec4e0f3bb2c77ac03a6154a8508d3930beb5f0f.1674154348.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: fix UAF issue in nfqnl_nf_hook_drop() when ops_init() failed</title>
<updated>2022-11-03T14:56:55+00:00</updated>
<author>
<name>Zhengchao Shao</name>
<email>shaozhengchao@huawei.com</email>
</author>
<published>2022-10-20T02:42:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=97ad240fd9aa9214497d14af2b91608e20856cac'/>
<id>97ad240fd9aa9214497d14af2b91608e20856cac</id>
<content type='text'>
[ Upstream commit d266935ac43d57586e311a087510fe6a084af742 ]

When the ops_init() interface is invoked to initialize the net, but
ops-&gt;init() fails, data is released. However, the ptr pointer in
net-&gt;gen is invalid. In this case, when nfqnl_nf_hook_drop() is invoked
to release the net, invalid address access occurs.

The process is as follows:
setup_net()
	ops_init()
		data = kzalloc(...)   ---&gt; alloc "data"
		net_assign_generic()  ---&gt; assign "date" to ptr in net-&gt;gen
		...
		ops-&gt;init()           ---&gt; failed
		...
		kfree(data);          ---&gt; ptr in net-&gt;gen is invalid
	...
	ops_exit_list()
		...
		nfqnl_nf_hook_drop()
			*q = nfnl_queue_pernet(net) ---&gt; q is invalid

The following is the Call Trace information:
BUG: KASAN: use-after-free in nfqnl_nf_hook_drop+0x264/0x280
Read of size 8 at addr ffff88810396b240 by task ip/15855
Call Trace:
&lt;TASK&gt;
dump_stack_lvl+0x8e/0xd1
print_report+0x155/0x454
kasan_report+0xba/0x1f0
nfqnl_nf_hook_drop+0x264/0x280
nf_queue_nf_hook_drop+0x8b/0x1b0
__nf_unregister_net_hook+0x1ae/0x5a0
nf_unregister_net_hooks+0xde/0x130
ops_exit_list+0xb0/0x170
setup_net+0x7ac/0xbd0
copy_net_ns+0x2e6/0x6b0
create_new_namespaces+0x382/0xa50
unshare_nsproxy_namespaces+0xa6/0x1c0
ksys_unshare+0x3a4/0x7e0
__x64_sys_unshare+0x2d/0x40
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
&lt;/TASK&gt;

Allocated by task 15855:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x30
__kasan_kmalloc+0xa1/0xb0
__kmalloc+0x49/0xb0
ops_init+0xe7/0x410
setup_net+0x5aa/0xbd0
copy_net_ns+0x2e6/0x6b0
create_new_namespaces+0x382/0xa50
unshare_nsproxy_namespaces+0xa6/0x1c0
ksys_unshare+0x3a4/0x7e0
__x64_sys_unshare+0x2d/0x40
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0

Freed by task 15855:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x30
kasan_save_free_info+0x2a/0x40
____kasan_slab_free+0x155/0x1b0
slab_free_freelist_hook+0x11b/0x220
__kmem_cache_free+0xa4/0x360
ops_init+0xb9/0x410
setup_net+0x5aa/0xbd0
copy_net_ns+0x2e6/0x6b0
create_new_namespaces+0x382/0xa50
unshare_nsproxy_namespaces+0xa6/0x1c0
ksys_unshare+0x3a4/0x7e0
__x64_sys_unshare+0x2d/0x40
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0

Fixes: f875bae06533 ("net: Automatically allocate per namespace data.")
Signed-off-by: Zhengchao Shao &lt;shaozhengchao@huawei.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit d266935ac43d57586e311a087510fe6a084af742 ]

When the ops_init() interface is invoked to initialize the net, but
ops-&gt;init() fails, data is released. However, the ptr pointer in
net-&gt;gen is invalid. In this case, when nfqnl_nf_hook_drop() is invoked
to release the net, invalid address access occurs.

The process is as follows:
setup_net()
	ops_init()
		data = kzalloc(...)   ---&gt; alloc "data"
		net_assign_generic()  ---&gt; assign "date" to ptr in net-&gt;gen
		...
		ops-&gt;init()           ---&gt; failed
		...
		kfree(data);          ---&gt; ptr in net-&gt;gen is invalid
	...
	ops_exit_list()
		...
		nfqnl_nf_hook_drop()
			*q = nfnl_queue_pernet(net) ---&gt; q is invalid

The following is the Call Trace information:
BUG: KASAN: use-after-free in nfqnl_nf_hook_drop+0x264/0x280
Read of size 8 at addr ffff88810396b240 by task ip/15855
Call Trace:
&lt;TASK&gt;
dump_stack_lvl+0x8e/0xd1
print_report+0x155/0x454
kasan_report+0xba/0x1f0
nfqnl_nf_hook_drop+0x264/0x280
nf_queue_nf_hook_drop+0x8b/0x1b0
__nf_unregister_net_hook+0x1ae/0x5a0
nf_unregister_net_hooks+0xde/0x130
ops_exit_list+0xb0/0x170
setup_net+0x7ac/0xbd0
copy_net_ns+0x2e6/0x6b0
create_new_namespaces+0x382/0xa50
unshare_nsproxy_namespaces+0xa6/0x1c0
ksys_unshare+0x3a4/0x7e0
__x64_sys_unshare+0x2d/0x40
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
&lt;/TASK&gt;

Allocated by task 15855:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x30
__kasan_kmalloc+0xa1/0xb0
__kmalloc+0x49/0xb0
ops_init+0xe7/0x410
setup_net+0x5aa/0xbd0
copy_net_ns+0x2e6/0x6b0
create_new_namespaces+0x382/0xa50
unshare_nsproxy_namespaces+0xa6/0x1c0
ksys_unshare+0x3a4/0x7e0
__x64_sys_unshare+0x2d/0x40
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0

Freed by task 15855:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x30
kasan_save_free_info+0x2a/0x40
____kasan_slab_free+0x155/0x1b0
slab_free_freelist_hook+0x11b/0x220
__kmem_cache_free+0xa4/0x360
ops_init+0xb9/0x410
setup_net+0x5aa/0xbd0
copy_net_ns+0x2e6/0x6b0
create_new_namespaces+0x382/0xa50
unshare_nsproxy_namespaces+0xa6/0x1c0
ksys_unshare+0x3a4/0x7e0
__x64_sys_unshare+0x2d/0x40
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0

Fixes: f875bae06533 ("net: Automatically allocate per namespace data.")
Signed-off-by: Zhengchao Shao &lt;shaozhengchao@huawei.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netns: add schedule point in ops_exit_list()</title>
<updated>2022-01-27T08:19:54+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2022-01-18T11:43:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d6bfcc8d9541a1cdf30eec29d84a66633bc4a22e'/>
<id>d6bfcc8d9541a1cdf30eec29d84a66633bc4a22e</id>
<content type='text'>
commit 2836615aa22de55b8fca5e32fe1b27a67cda625e upstream.

When under stress, cleanup_net() can have to dismantle
netns in big numbers. ops_exit_list() currently calls
many helpers [1] that have no schedule point, and we can
end up with soft lockups, particularly on hosts
with many cpus.

Even for moderate amount of netns processed by cleanup_net()
this patch avoids latency spikes.

[1] Some of these helpers like fib_sync_up() and fib_sync_down_dev()
are very slow because net/ipv4/fib_semantics.c uses host-wide hash tables,
and ifindex is used as the only input of two hash functions.
    ifindexes tend to be the same for all netns (lo.ifindex==1 per instance)
    This will be fixed in a separate patch.

Fixes: 72ad937abd0a ("net: Add support for batching network namespace cleanups")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 2836615aa22de55b8fca5e32fe1b27a67cda625e upstream.

When under stress, cleanup_net() can have to dismantle
netns in big numbers. ops_exit_list() currently calls
many helpers [1] that have no schedule point, and we can
end up with soft lockups, particularly on hosts
with many cpus.

Even for moderate amount of netns processed by cleanup_net()
this patch avoids latency spikes.

[1] Some of these helpers like fib_sync_up() and fib_sync_down_dev()
are very slow because net/ipv4/fib_semantics.c uses host-wide hash tables,
and ifindex is used as the only input of two hash functions.
    ifindexes tend to be the same for all netns (lo.ifindex==1 per instance)
    This will be fixed in a separate patch.

Fixes: 72ad937abd0a ("net: Add support for batching network namespace cleanups")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: net_namespace: Fix undefined member in key_remove_domain()</title>
<updated>2021-11-17T08:48:34+00:00</updated>
<author>
<name>Yajun Deng</name>
<email>yajun.deng@linux.dev</email>
</author>
<published>2021-09-18T09:04:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bd76ec43f14e16658804f6c7db10d1651da83123'/>
<id>bd76ec43f14e16658804f6c7db10d1651da83123</id>
<content type='text'>
[ Upstream commit aed0826b0cf2e488900ab92193893e803d65c070 ]

The key_domain member in struct net only exists if we define CONFIG_KEYS.
So we should add the define when we used key_domain.

Fixes: 9b242610514f ("keys: Network namespace domain tag")
Signed-off-by: Yajun Deng &lt;yajun.deng@linux.dev&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit aed0826b0cf2e488900ab92193893e803d65c070 ]

The key_domain member in struct net only exists if we define CONFIG_KEYS.
So we should add the define when we used key_domain.

Fixes: 9b242610514f ("keys: Network namespace domain tag")
Signed-off-by: Yajun Deng &lt;yajun.deng@linux.dev&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netns: protect netns ID lookups with RCU</title>
<updated>2021-09-15T07:47:31+00:00</updated>
<author>
<name>Guillaume Nault</name>
<email>gnault@redhat.com</email>
</author>
<published>2020-01-13T21:39:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=252fad3d023484d3f258ebb29979960c345b9e80'/>
<id>252fad3d023484d3f258ebb29979960c345b9e80</id>
<content type='text'>
commit 2dce224f469f060b9998a5a869151ef83c08ce77 upstream.

__peernet2id() can be protected by RCU as it only calls idr_for_each(),
which is RCU-safe, and never modifies the nsid table.

rtnl_net_dumpid() can also do lockless lookups. It does two nested
idr_for_each() calls on nsid tables (one direct call and one indirect
call because of rtnl_net_dumpid_one() calling __peernet2id()). The
netnsid tables are never updated. Therefore it is safe to not take the
nsid_lock and run within an RCU-critical section instead.

Signed-off-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Håkon Bugge &lt;haakon.bugge@oracle.com&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 2dce224f469f060b9998a5a869151ef83c08ce77 upstream.

__peernet2id() can be protected by RCU as it only calls idr_for_each(),
which is RCU-safe, and never modifies the nsid table.

rtnl_net_dumpid() can also do lockless lookups. It does two nested
idr_for_each() calls on nsid tables (one direct call and one indirect
call because of rtnl_net_dumpid_one() calling __peernet2id()). The
netnsid tables are never updated. Therefore it is safe to not take the
nsid_lock and run within an RCU-critical section instead.

Signed-off-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Håkon Bugge &lt;haakon.bugge@oracle.com&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>net: make get_net_ns return error if NET_NS is disabled</title>
<updated>2021-06-23T12:41:25+00:00</updated>
<author>
<name>Changbin Du</name>
<email>changbin.du@gmail.com</email>
</author>
<published>2021-06-11T14:29:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b0bb49b0fbc30bc22ff8a70e8fc857dae01187e0'/>
<id>b0bb49b0fbc30bc22ff8a70e8fc857dae01187e0</id>
<content type='text'>
[ Upstream commit ea6932d70e223e02fea3ae20a4feff05d7c1ea9a ]

There is a panic in socket ioctl cmd SIOCGSKNS when NET_NS is not enabled.
The reason is that nsfs tries to access ns-&gt;ops but the proc_ns_operations
is not implemented in this case.

[7.670023] Unable to handle kernel NULL pointer dereference at virtual address 00000010
[7.670268] pgd = 32b54000
[7.670544] [00000010] *pgd=00000000
[7.671861] Internal error: Oops: 5 [#1] SMP ARM
[7.672315] Modules linked in:
[7.672918] CPU: 0 PID: 1 Comm: systemd Not tainted 5.13.0-rc3-00375-g6799d4f2da49 #16
[7.673309] Hardware name: Generic DT based system
[7.673642] PC is at nsfs_evict+0x24/0x30
[7.674486] LR is at clear_inode+0x20/0x9c

The same to tun SIOCGSKNS command.

To fix this problem, we make get_net_ns() return -EINVAL when NET_NS is
disabled. Meanwhile move it to right place net/core/net_namespace.c.

Signed-off-by: Changbin Du &lt;changbin.du@gmail.com&gt;
Fixes: c62cce2caee5 ("net: add an ioctl to get a socket network namespace")
Cc: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Cc: Jakub Kicinski &lt;kuba@kernel.org&gt;
Cc: David Laight &lt;David.Laight@ACULAB.COM&gt;
Cc: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Suggested-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit ea6932d70e223e02fea3ae20a4feff05d7c1ea9a ]

There is a panic in socket ioctl cmd SIOCGSKNS when NET_NS is not enabled.
The reason is that nsfs tries to access ns-&gt;ops but the proc_ns_operations
is not implemented in this case.

[7.670023] Unable to handle kernel NULL pointer dereference at virtual address 00000010
[7.670268] pgd = 32b54000
[7.670544] [00000010] *pgd=00000000
[7.671861] Internal error: Oops: 5 [#1] SMP ARM
[7.672315] Modules linked in:
[7.672918] CPU: 0 PID: 1 Comm: systemd Not tainted 5.13.0-rc3-00375-g6799d4f2da49 #16
[7.673309] Hardware name: Generic DT based system
[7.673642] PC is at nsfs_evict+0x24/0x30
[7.674486] LR is at clear_inode+0x20/0x9c

The same to tun SIOCGSKNS command.

To fix this problem, we make get_net_ns() return -EINVAL when NET_NS is
disabled. Meanwhile move it to right place net/core/net_namespace.c.

Signed-off-by: Changbin Du &lt;changbin.du@gmail.com&gt;
Fixes: c62cce2caee5 ("net: add an ioctl to get a socket network namespace")
Cc: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Cc: Jakub Kicinski &lt;kuba@kernel.org&gt;
Cc: David Laight &lt;David.Laight@ACULAB.COM&gt;
Cc: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Suggested-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
