<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/include/net, branch v4.19.306</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>Bluetooth: Fix bogus check for re-auth no supported with non-ssp</title>
<updated>2024-01-25T22:33:34+00:00</updated>
<author>
<name>Luiz Augusto von Dentz</name>
<email>luiz.von.dentz@intel.com</email>
</author>
<published>2023-11-30T13:58:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f7f627ac761b2fb0c487e5aaff1585f1014ab9a6'/>
<id>f7f627ac761b2fb0c487e5aaff1585f1014ab9a6</id>
<content type='text'>
[ Upstream commit d03376c185926098cb4d668d6458801eb785c0a5 ]

This reverts 19f8def031bfa50c579149b200bfeeb919727b27
"Bluetooth: Fix auth_complete_evt for legacy units" which seems to be
working around a bug on a broken controller rather then any limitation
imposed by the Bluetooth spec, in fact if there ws not possible to
re-auth the command shall fail not succeed.

Fixes: 19f8def031bf ("Bluetooth: Fix auth_complete_evt for legacy units")
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.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 d03376c185926098cb4d668d6458801eb785c0a5 ]

This reverts 19f8def031bfa50c579149b200bfeeb919727b27
"Bluetooth: Fix auth_complete_evt for legacy units" which seems to be
working around a bug on a broken controller rather then any limitation
imposed by the Bluetooth spec, in fact if there ws not possible to
re-auth the command shall fail not succeed.

Fixes: 19f8def031bf ("Bluetooth: Fix auth_complete_evt for legacy units")
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6: remove max_size check inline with ipv4</title>
<updated>2024-01-15T17:23:44+00:00</updated>
<author>
<name>Jon Maxwell</name>
<email>jmaxwell37@gmail.com</email>
</author>
<published>2024-01-13T00:53:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=95372b040ae689293c6863b90049f1af68410c8b'/>
<id>95372b040ae689293c6863b90049f1af68410c8b</id>
<content type='text'>
commit af6d10345ca76670c1b7c37799f0d5576ccef277 upstream.

In ip6_dst_gc() replace:

  if (entries &gt; gc_thresh)

With:

  if (entries &gt; ops-&gt;gc_thresh)

Sending Ipv6 packets in a loop via a raw socket triggers an issue where a
route is cloned by ip6_rt_cache_alloc() for each packet sent. This quickly
consumes the Ipv6 max_size threshold which defaults to 4096 resulting in
these warnings:

[1]   99.187805] dst_alloc: 7728 callbacks suppressed
[2] Route cache is full: consider increasing sysctl net.ipv6.route.max_size.
.
.
[300] Route cache is full: consider increasing sysctl net.ipv6.route.max_size.

When this happens the packet is dropped and sendto() gets a network is
unreachable error:

remaining pkt 200557 errno 101
remaining pkt 196462 errno 101
.
.
remaining pkt 126821 errno 101

Implement David Aherns suggestion to remove max_size check seeing that Ipv6
has a GC to manage memory usage. Ipv4 already does not check max_size.

Here are some memory comparisons for Ipv4 vs Ipv6 with the patch:

Test by running 5 instances of a program that sends UDP packets to a raw
socket 5000000 times. Compare Ipv4 and Ipv6 performance with a similar
program.

Ipv4:

Before test:

MemFree:        29427108 kB
Slab:             237612 kB

ip6_dst_cache       1912   2528    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        2881   3990    192   42    2 : tunables    0    0    0

During test:

MemFree:        29417608 kB
Slab:             247712 kB

ip6_dst_cache       1912   2528    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache       44394  44394    192   42    2 : tunables    0    0    0

After test:

MemFree:        29422308 kB
Slab:             238104 kB

ip6_dst_cache       1912   2528    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        3048   4116    192   42    2 : tunables    0    0    0

Ipv6 with patch:

Errno 101 errors are not observed anymore with the patch.

Before test:

MemFree:        29422308 kB
Slab:             238104 kB

ip6_dst_cache       1912   2528    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        3048   4116    192   42    2 : tunables    0    0    0

During Test:

MemFree:        29431516 kB
Slab:             240940 kB

ip6_dst_cache      11980  12064    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        3048   4116    192   42    2 : tunables    0    0    0

After Test:

MemFree:        29441816 kB
Slab:             238132 kB

ip6_dst_cache       1902   2432    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        3048   4116    192   42    2 : tunables    0    0    0

Tested-by: Andrea Mayer &lt;andrea.mayer@uniroma2.it&gt;
Signed-off-by: Jon Maxwell &lt;jmaxwell37@gmail.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20230112012532.311021-1-jmaxwell37@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Suraj Jitindar Singh &lt;surajjs@amazon.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 4.19.x
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 af6d10345ca76670c1b7c37799f0d5576ccef277 upstream.

In ip6_dst_gc() replace:

  if (entries &gt; gc_thresh)

With:

  if (entries &gt; ops-&gt;gc_thresh)

Sending Ipv6 packets in a loop via a raw socket triggers an issue where a
route is cloned by ip6_rt_cache_alloc() for each packet sent. This quickly
consumes the Ipv6 max_size threshold which defaults to 4096 resulting in
these warnings:

[1]   99.187805] dst_alloc: 7728 callbacks suppressed
[2] Route cache is full: consider increasing sysctl net.ipv6.route.max_size.
.
.
[300] Route cache is full: consider increasing sysctl net.ipv6.route.max_size.

When this happens the packet is dropped and sendto() gets a network is
unreachable error:

remaining pkt 200557 errno 101
remaining pkt 196462 errno 101
.
.
remaining pkt 126821 errno 101

Implement David Aherns suggestion to remove max_size check seeing that Ipv6
has a GC to manage memory usage. Ipv4 already does not check max_size.

Here are some memory comparisons for Ipv4 vs Ipv6 with the patch:

Test by running 5 instances of a program that sends UDP packets to a raw
socket 5000000 times. Compare Ipv4 and Ipv6 performance with a similar
program.

Ipv4:

Before test:

MemFree:        29427108 kB
Slab:             237612 kB

ip6_dst_cache       1912   2528    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        2881   3990    192   42    2 : tunables    0    0    0

During test:

MemFree:        29417608 kB
Slab:             247712 kB

ip6_dst_cache       1912   2528    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache       44394  44394    192   42    2 : tunables    0    0    0

After test:

MemFree:        29422308 kB
Slab:             238104 kB

ip6_dst_cache       1912   2528    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        3048   4116    192   42    2 : tunables    0    0    0

Ipv6 with patch:

Errno 101 errors are not observed anymore with the patch.

Before test:

MemFree:        29422308 kB
Slab:             238104 kB

ip6_dst_cache       1912   2528    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        3048   4116    192   42    2 : tunables    0    0    0

During Test:

MemFree:        29431516 kB
Slab:             240940 kB

ip6_dst_cache      11980  12064    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        3048   4116    192   42    2 : tunables    0    0    0

After Test:

MemFree:        29441816 kB
Slab:             238132 kB

ip6_dst_cache       1902   2432    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        3048   4116    192   42    2 : tunables    0    0    0

Tested-by: Andrea Mayer &lt;andrea.mayer@uniroma2.it&gt;
Signed-off-by: Jon Maxwell &lt;jmaxwell37@gmail.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20230112012532.311021-1-jmaxwell37@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Suraj Jitindar Singh &lt;surajjs@amazon.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 4.19.x
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6: make ip6_rt_gc_expire an atomic_t</title>
<updated>2024-01-15T17:23:44+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2024-01-13T00:53:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b4cfbeaebeb355dbaefb218470055de2e8a73020'/>
<id>b4cfbeaebeb355dbaefb218470055de2e8a73020</id>
<content type='text'>
commit 9cb7c013420f98fa6fd12fc6a5dc055170c108db upstream.

Reads and Writes to ip6_rt_gc_expire always have been racy,
as syzbot reported lately [1]

There is a possible risk of under-flow, leading
to unexpected high value passed to fib6_run_gc(),
although I have not observed this in the field.

Hosts hitting ip6_dst_gc() very hard are under pretty bad
state anyway.

[1]
BUG: KCSAN: data-race in ip6_dst_gc / ip6_dst_gc

read-write to 0xffff888102110744 of 4 bytes by task 13165 on cpu 1:
 ip6_dst_gc+0x1f3/0x220 net/ipv6/route.c:3311
 dst_alloc+0x9b/0x160 net/core/dst.c:86
 ip6_dst_alloc net/ipv6/route.c:344 [inline]
 icmp6_dst_alloc+0xb2/0x360 net/ipv6/route.c:3261
 mld_sendpack+0x2b9/0x580 net/ipv6/mcast.c:1807
 mld_send_cr net/ipv6/mcast.c:2119 [inline]
 mld_ifc_work+0x576/0x800 net/ipv6/mcast.c:2651
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

read-write to 0xffff888102110744 of 4 bytes by task 11607 on cpu 0:
 ip6_dst_gc+0x1f3/0x220 net/ipv6/route.c:3311
 dst_alloc+0x9b/0x160 net/core/dst.c:86
 ip6_dst_alloc net/ipv6/route.c:344 [inline]
 icmp6_dst_alloc+0xb2/0x360 net/ipv6/route.c:3261
 mld_sendpack+0x2b9/0x580 net/ipv6/mcast.c:1807
 mld_send_cr net/ipv6/mcast.c:2119 [inline]
 mld_ifc_work+0x576/0x800 net/ipv6/mcast.c:2651
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

value changed: 0x00000bb3 -&gt; 0x00000ba9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 11607 Comm: kworker/0:21 Not tainted 5.18.0-rc1-syzkaller-00037-g42e7a03d3bad-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: mld mld_ifc_work

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20220413181333.649424-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
[ 4.19: context adjustment in include/net/netns/ipv6.h ]
Signed-off-by: Suraj Jitindar Singh &lt;surajjs@amazon.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 4.19.x
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 9cb7c013420f98fa6fd12fc6a5dc055170c108db upstream.

Reads and Writes to ip6_rt_gc_expire always have been racy,
as syzbot reported lately [1]

There is a possible risk of under-flow, leading
to unexpected high value passed to fib6_run_gc(),
although I have not observed this in the field.

Hosts hitting ip6_dst_gc() very hard are under pretty bad
state anyway.

[1]
BUG: KCSAN: data-race in ip6_dst_gc / ip6_dst_gc

read-write to 0xffff888102110744 of 4 bytes by task 13165 on cpu 1:
 ip6_dst_gc+0x1f3/0x220 net/ipv6/route.c:3311
 dst_alloc+0x9b/0x160 net/core/dst.c:86
 ip6_dst_alloc net/ipv6/route.c:344 [inline]
 icmp6_dst_alloc+0xb2/0x360 net/ipv6/route.c:3261
 mld_sendpack+0x2b9/0x580 net/ipv6/mcast.c:1807
 mld_send_cr net/ipv6/mcast.c:2119 [inline]
 mld_ifc_work+0x576/0x800 net/ipv6/mcast.c:2651
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

read-write to 0xffff888102110744 of 4 bytes by task 11607 on cpu 0:
 ip6_dst_gc+0x1f3/0x220 net/ipv6/route.c:3311
 dst_alloc+0x9b/0x160 net/core/dst.c:86
 ip6_dst_alloc net/ipv6/route.c:344 [inline]
 icmp6_dst_alloc+0xb2/0x360 net/ipv6/route.c:3261
 mld_sendpack+0x2b9/0x580 net/ipv6/mcast.c:1807
 mld_send_cr net/ipv6/mcast.c:2119 [inline]
 mld_ifc_work+0x576/0x800 net/ipv6/mcast.c:2651
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

value changed: 0x00000bb3 -&gt; 0x00000ba9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 11607 Comm: kworker/0:21 Not tainted 5.18.0-rc1-syzkaller-00037-g42e7a03d3bad-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: mld mld_ifc_work

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20220413181333.649424-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
[ 4.19: context adjustment in include/net/netns/ipv6.h ]
Signed-off-by: Suraj Jitindar Singh &lt;surajjs@amazon.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 4.19.x
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net/dst: use a smaller percpu_counter batch for dst entries accounting</title>
<updated>2024-01-15T17:23:44+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2024-01-13T00:53:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9635bd0a5296e2e725c6b33e530d0ef582e2f64e'/>
<id>9635bd0a5296e2e725c6b33e530d0ef582e2f64e</id>
<content type='text'>
commit cf86a086a18095e33e0637cb78cda1fcf5280852 upstream.

percpu_counter_add() uses a default batch size which is quite big
on platforms with 256 cpus. (2*256 -&gt; 512)

This means dst_entries_get_fast() can be off by +/- 2*(nr_cpus^2)
(131072 on servers with 256 cpus)

Reduce the batch size to something more reasonable, and
add logic to ip6_dst_gc() to call dst_entries_get_slow()
before calling the _very_ expensive fib6_run_gc() function.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Suraj Jitindar Singh &lt;surajjs@amazon.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 4.19.x
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 cf86a086a18095e33e0637cb78cda1fcf5280852 upstream.

percpu_counter_add() uses a default batch size which is quite big
on platforms with 256 cpus. (2*256 -&gt; 512)

This means dst_entries_get_fast() can be off by +/- 2*(nr_cpus^2)
(131072 on servers with 256 cpus)

Reduce the batch size to something more reasonable, and
add logic to ip6_dst_gc() to call dst_entries_get_slow()
before calling the _very_ expensive fib6_run_gc() function.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Suraj Jitindar Singh &lt;surajjs@amazon.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 4.19.x
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drop_monitor: Require 'CAP_SYS_ADMIN' when joining "events" group</title>
<updated>2023-12-13T16:42:20+00:00</updated>
<author>
<name>Ido Schimmel</name>
<email>idosch@nvidia.com</email>
</author>
<published>2023-12-11T12:42:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=855a2b559df16b0cf7b5dcc1a31042347afcabf2'/>
<id>855a2b559df16b0cf7b5dcc1a31042347afcabf2</id>
<content type='text'>
commit e03781879a0d524ce3126678d50a80484a513c4b upstream.

The "NET_DM" generic netlink family notifies drop locations over the
"events" multicast group. This is problematic since by default generic
netlink allows non-root users to listen to these notifications.

Fix by adding a new field to the generic netlink multicast group
structure that when set prevents non-root users or root without the
'CAP_SYS_ADMIN' capability (in the user namespace owning the network
namespace) from joining the group. Set this field for the "events"
group. Use 'CAP_SYS_ADMIN' rather than 'CAP_NET_ADMIN' because of the
nature of the information that is shared over this group.

Note that the capability check in this case will always be performed
against the initial user namespace since the family is not netns aware
and only operates in the initial network namespace.

A new field is added to the structure rather than using the "flags"
field because the existing field uses uAPI flags and it is inappropriate
to add a new uAPI flag for an internal kernel check. In net-next we can
rework the "flags" field to use internal flags and fold the new field
into it. But for now, in order to reduce the amount of changes, add a
new field.

Since the information can only be consumed by root, mark the control
plane operations that start and stop the tracing as root-only using the
'GENL_ADMIN_PERM' flag.

Tested using [1].

Before:

 # capsh -- -c ./dm_repo
 # capsh --drop=cap_sys_admin -- -c ./dm_repo

After:

 # capsh -- -c ./dm_repo
 # capsh --drop=cap_sys_admin -- -c ./dm_repo
 Failed to join "events" multicast group

[1]
 $ cat dm.c
 #include &lt;stdio.h&gt;
 #include &lt;netlink/genl/ctrl.h&gt;
 #include &lt;netlink/genl/genl.h&gt;
 #include &lt;netlink/socket.h&gt;

 int main(int argc, char **argv)
 {
 	struct nl_sock *sk;
 	int grp, err;

 	sk = nl_socket_alloc();
 	if (!sk) {
 		fprintf(stderr, "Failed to allocate socket\n");
 		return -1;
 	}

 	err = genl_connect(sk);
 	if (err) {
 		fprintf(stderr, "Failed to connect socket\n");
 		return err;
 	}

 	grp = genl_ctrl_resolve_grp(sk, "NET_DM", "events");
 	if (grp &lt; 0) {
 		fprintf(stderr,
 			"Failed to resolve \"events\" multicast group\n");
 		return grp;
 	}

 	err = nl_socket_add_memberships(sk, grp, NFNLGRP_NONE);
 	if (err) {
 		fprintf(stderr, "Failed to join \"events\" multicast group\n");
 		return err;
 	}

 	return 0;
 }
 $ gcc -I/usr/include/libnl3 -lnl-3 -lnl-genl-3 -o dm_repo dm.c

Fixes: 9a8afc8d3962 ("Network Drop Monitor: Adding drop monitor implementation &amp; Netlink protocol")
Reported-by: "The UK's National Cyber Security Centre (NCSC)" &lt;security@ncsc.gov.uk&gt;
Signed-off-by: Ido Schimmel &lt;idosch@nvidia.com&gt;
Reviewed-by: Jacob Keller &lt;jacob.e.keller@intel.com&gt;
Reviewed-by: Jiri Pirko &lt;jiri@nvidia.com&gt;
Link: https://lore.kernel.org/r/20231206213102.1824398-3-idosch@nvidia.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&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 e03781879a0d524ce3126678d50a80484a513c4b upstream.

The "NET_DM" generic netlink family notifies drop locations over the
"events" multicast group. This is problematic since by default generic
netlink allows non-root users to listen to these notifications.

Fix by adding a new field to the generic netlink multicast group
structure that when set prevents non-root users or root without the
'CAP_SYS_ADMIN' capability (in the user namespace owning the network
namespace) from joining the group. Set this field for the "events"
group. Use 'CAP_SYS_ADMIN' rather than 'CAP_NET_ADMIN' because of the
nature of the information that is shared over this group.

Note that the capability check in this case will always be performed
against the initial user namespace since the family is not netns aware
and only operates in the initial network namespace.

A new field is added to the structure rather than using the "flags"
field because the existing field uses uAPI flags and it is inappropriate
to add a new uAPI flag for an internal kernel check. In net-next we can
rework the "flags" field to use internal flags and fold the new field
into it. But for now, in order to reduce the amount of changes, add a
new field.

Since the information can only be consumed by root, mark the control
plane operations that start and stop the tracing as root-only using the
'GENL_ADMIN_PERM' flag.

Tested using [1].

Before:

 # capsh -- -c ./dm_repo
 # capsh --drop=cap_sys_admin -- -c ./dm_repo

After:

 # capsh -- -c ./dm_repo
 # capsh --drop=cap_sys_admin -- -c ./dm_repo
 Failed to join "events" multicast group

[1]
 $ cat dm.c
 #include &lt;stdio.h&gt;
 #include &lt;netlink/genl/ctrl.h&gt;
 #include &lt;netlink/genl/genl.h&gt;
 #include &lt;netlink/socket.h&gt;

 int main(int argc, char **argv)
 {
 	struct nl_sock *sk;
 	int grp, err;

 	sk = nl_socket_alloc();
 	if (!sk) {
 		fprintf(stderr, "Failed to allocate socket\n");
 		return -1;
 	}

 	err = genl_connect(sk);
 	if (err) {
 		fprintf(stderr, "Failed to connect socket\n");
 		return err;
 	}

 	grp = genl_ctrl_resolve_grp(sk, "NET_DM", "events");
 	if (grp &lt; 0) {
 		fprintf(stderr,
 			"Failed to resolve \"events\" multicast group\n");
 		return grp;
 	}

 	err = nl_socket_add_memberships(sk, grp, NFNLGRP_NONE);
 	if (err) {
 		fprintf(stderr, "Failed to join \"events\" multicast group\n");
 		return err;
 	}

 	return 0;
 }
 $ gcc -I/usr/include/libnl3 -lnl-3 -lnl-genl-3 -o dm_repo dm.c

Fixes: 9a8afc8d3962 ("Network Drop Monitor: Adding drop monitor implementation &amp; Netlink protocol")
Reported-by: "The UK's National Cyber Security Centre (NCSC)" &lt;security@ncsc.gov.uk&gt;
Signed-off-by: Ido Schimmel &lt;idosch@nvidia.com&gt;
Reviewed-by: Jacob Keller &lt;jacob.e.keller@intel.com&gt;
Reviewed-by: Jiri Pirko &lt;jiri@nvidia.com&gt;
Link: https://lore.kernel.org/r/20231206213102.1824398-3-idosch@nvidia.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>genetlink: add CAP_NET_ADMIN test for multicast bind</title>
<updated>2023-12-13T16:42:20+00:00</updated>
<author>
<name>Ido Schimmel</name>
<email>idosch@nvidia.com</email>
</author>
<published>2023-12-11T12:42:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=30cc13fe89401588a52a0aa148dceff8f3796486'/>
<id>30cc13fe89401588a52a0aa148dceff8f3796486</id>
<content type='text'>
This is a partial backport of upstream commit 4d54cc32112d ("mptcp:
avoid lock_fast usage in accept path"). It is only a partial backport
because the patch in the link below was erroneously squash-merged into
upstream commit 4d54cc32112d ("mptcp: avoid lock_fast usage in accept
path"). Below is the original patch description from Florian Westphal:

"
genetlink sets NL_CFG_F_NONROOT_RECV for its netlink socket so anyone can
subscribe to multicast messages.

rtnetlink doesn't allow this unconditionally,  rtnetlink_bind() restricts
bind requests to CAP_NET_ADMIN for a few groups.

This allows to set GENL_UNS_ADMIN_PERM flag on genl mcast groups to
mandate CAP_NET_ADMIN.

This will be used by the upcoming mptcp netlink event facility which
exposes the token (mptcp connection identifier) to userspace.
"

Link: https://lore.kernel.org/mptcp/20210213000001.379332-8-mathew.j.martineau@linux.intel.com/
Signed-off-by: Ido Schimmel &lt;idosch@nvidia.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>
This is a partial backport of upstream commit 4d54cc32112d ("mptcp:
avoid lock_fast usage in accept path"). It is only a partial backport
because the patch in the link below was erroneously squash-merged into
upstream commit 4d54cc32112d ("mptcp: avoid lock_fast usage in accept
path"). Below is the original patch description from Florian Westphal:

"
genetlink sets NL_CFG_F_NONROOT_RECV for its netlink socket so anyone can
subscribe to multicast messages.

rtnetlink doesn't allow this unconditionally,  rtnetlink_bind() restricts
bind requests to CAP_NET_ADMIN for a few groups.

This allows to set GENL_UNS_ADMIN_PERM flag on genl mcast groups to
mandate CAP_NET_ADMIN.

This will be used by the upcoming mptcp netlink event facility which
exposes the token (mptcp connection identifier) to userspace.
"

Link: https://lore.kernel.org/mptcp/20210213000001.379332-8-mathew.j.martineau@linux.intel.com/
Signed-off-by: Ido Schimmel &lt;idosch@nvidia.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: annotate data-races around sk-&gt;sk_dst_pending_confirm</title>
<updated>2023-11-28T16:46:31+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-09-21T20:28:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ac41b10e834f5f7479f91220668e90c505808d1c'/>
<id>ac41b10e834f5f7479f91220668e90c505808d1c</id>
<content type='text'>
[ Upstream commit eb44ad4e635132754bfbcb18103f1dcb7058aedd ]

This field can be read or written without socket lock being held.

Add annotations to avoid load-store tearing.

Signed-off-by: Eric Dumazet &lt;edumazet@google.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 eb44ad4e635132754bfbcb18103f1dcb7058aedd ]

This field can be read or written without socket lock being held.

Add annotations to avoid load-store tearing.

Signed-off-by: Eric Dumazet &lt;edumazet@google.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>net: annotate data-races around sk-&gt;sk_tx_queue_mapping</title>
<updated>2023-11-28T16:46:31+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-09-21T20:28:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bd4f1843a141fc77995108b08d9cc07f67d5d894'/>
<id>bd4f1843a141fc77995108b08d9cc07f67d5d894</id>
<content type='text'>
[ Upstream commit 0bb4d124d34044179b42a769a0c76f389ae973b6 ]

This field can be read or written without socket lock being held.

Add annotations to avoid load-store tearing.

Signed-off-by: Eric Dumazet &lt;edumazet@google.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 0bb4d124d34044179b42a769a0c76f389ae973b6 ]

This field can be read or written without socket lock being held.

Add annotations to avoid load-store tearing.

Signed-off-by: Eric Dumazet &lt;edumazet@google.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>Bluetooth: hci_core: Fix build warnings</title>
<updated>2023-10-25T09:16:56+00:00</updated>
<author>
<name>Luiz Augusto von Dentz</name>
<email>luiz.von.dentz@intel.com</email>
</author>
<published>2023-09-15T21:42:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=194ab82c1ea187512ff2f822124bd05b63fc9f76'/>
<id>194ab82c1ea187512ff2f822124bd05b63fc9f76</id>
<content type='text'>
[ Upstream commit dcda165706b9fbfd685898d46a6749d7d397e0c0 ]

This fixes the following warnings:

net/bluetooth/hci_core.c: In function ‘hci_register_dev’:
net/bluetooth/hci_core.c:2620:54: warning: ‘%d’ directive output may
be truncated writing between 1 and 10 bytes into a region of size 5
[-Wformat-truncation=]
 2620 |         snprintf(hdev-&gt;name, sizeof(hdev-&gt;name), "hci%d", id);
      |                                                      ^~
net/bluetooth/hci_core.c:2620:50: note: directive argument in the range
[0, 2147483647]
 2620 |         snprintf(hdev-&gt;name, sizeof(hdev-&gt;name), "hci%d", id);
      |                                                  ^~~~~~~
net/bluetooth/hci_core.c:2620:9: note: ‘snprintf’ output between 5 and
14 bytes into a destination of size 8
 2620 |         snprintf(hdev-&gt;name, sizeof(hdev-&gt;name), "hci%d", id);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.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 dcda165706b9fbfd685898d46a6749d7d397e0c0 ]

This fixes the following warnings:

net/bluetooth/hci_core.c: In function ‘hci_register_dev’:
net/bluetooth/hci_core.c:2620:54: warning: ‘%d’ directive output may
be truncated writing between 1 and 10 bytes into a region of size 5
[-Wformat-truncation=]
 2620 |         snprintf(hdev-&gt;name, sizeof(hdev-&gt;name), "hci%d", id);
      |                                                      ^~
net/bluetooth/hci_core.c:2620:50: note: directive argument in the range
[0, 2147483647]
 2620 |         snprintf(hdev-&gt;name, sizeof(hdev-&gt;name), "hci%d", id);
      |                                                  ^~~~~~~
net/bluetooth/hci_core.c:2620:9: note: ‘snprintf’ output between 5 and
14 bytes into a destination of size 8
 2620 |         snprintf(hdev-&gt;name, sizeof(hdev-&gt;name), "hci%d", id);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tcp: fix excessive TLP and RACK timeouts from HZ rounding</title>
<updated>2023-10-25T09:16:46+00:00</updated>
<author>
<name>Neal Cardwell</name>
<email>ncardwell@google.com</email>
</author>
<published>2023-10-15T17:47:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6d022a7abf7278f5317bf3000e4ba5d8e55875dc'/>
<id>6d022a7abf7278f5317bf3000e4ba5d8e55875dc</id>
<content type='text'>
commit 1c2709cfff1dedbb9591e989e2f001484208d914 upstream.

We discovered from packet traces of slow loss recovery on kernels with
the default HZ=250 setting (and min_rtt &lt; 1ms) that after reordering,
when receiving a SACKed sequence range, the RACK reordering timer was
firing after about 16ms rather than the desired value of roughly
min_rtt/4 + 2ms. The problem is largely due to the RACK reorder timer
calculation adding in TCP_TIMEOUT_MIN, which is 2 jiffies. On kernels
with HZ=250, this is 2*4ms = 8ms. The TLP timer calculation has the
exact same issue.

This commit fixes the TLP transmit timer and RACK reordering timer
floor calculation to more closely match the intended 2ms floor even on
kernels with HZ=250. It does this by adding in a new
TCP_TIMEOUT_MIN_US floor of 2000 us and then converting to jiffies,
instead of the current approach of converting to jiffies and then
adding th TCP_TIMEOUT_MIN value of 2 jiffies.

Our testing has verified that on kernels with HZ=1000, as expected,
this does not produce significant changes in behavior, but on kernels
with the default HZ=250 the latency improvement can be large. For
example, our tests show that for HZ=250 kernels at low RTTs this fix
roughly halves the latency for the RACK reorder timer: instead of
mostly firing at 16ms it mostly fires at 8ms.

Suggested-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Signed-off-by: Yuchung Cheng &lt;ycheng@google.com&gt;
Fixes: bb4d991a28cc ("tcp: adjust tail loss probe timeout")
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20231015174700.2206872-1-ncardwell.sw@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&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 1c2709cfff1dedbb9591e989e2f001484208d914 upstream.

We discovered from packet traces of slow loss recovery on kernels with
the default HZ=250 setting (and min_rtt &lt; 1ms) that after reordering,
when receiving a SACKed sequence range, the RACK reordering timer was
firing after about 16ms rather than the desired value of roughly
min_rtt/4 + 2ms. The problem is largely due to the RACK reorder timer
calculation adding in TCP_TIMEOUT_MIN, which is 2 jiffies. On kernels
with HZ=250, this is 2*4ms = 8ms. The TLP timer calculation has the
exact same issue.

This commit fixes the TLP transmit timer and RACK reordering timer
floor calculation to more closely match the intended 2ms floor even on
kernels with HZ=250. It does this by adding in a new
TCP_TIMEOUT_MIN_US floor of 2000 us and then converting to jiffies,
instead of the current approach of converting to jiffies and then
adding th TCP_TIMEOUT_MIN value of 2 jiffies.

Our testing has verified that on kernels with HZ=1000, as expected,
this does not produce significant changes in behavior, but on kernels
with the default HZ=250 the latency improvement can be large. For
example, our tests show that for HZ=250 kernels at low RTTs this fix
roughly halves the latency for the RACK reorder timer: instead of
mostly firing at 16ms it mostly fires at 8ms.

Suggested-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Signed-off-by: Yuchung Cheng &lt;ycheng@google.com&gt;
Fixes: bb4d991a28cc ("tcp: adjust tail loss probe timeout")
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20231015174700.2206872-1-ncardwell.sw@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
