<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/include, branch v6.0.7</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>net/mlx5: Fix possible use-after-free in async command interface</title>
<updated>2022-11-03T15:00:34+00:00</updated>
<author>
<name>Tariq Toukan</name>
<email>tariqt@nvidia.com</email>
</author>
<published>2022-10-26T13:51:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0aa3ee1e4e5c9ed5dda11249450d609c3072c54e'/>
<id>0aa3ee1e4e5c9ed5dda11249450d609c3072c54e</id>
<content type='text'>
[ Upstream commit bacd22df95147ed673bec4692ab2d4d585935241 ]

mlx5_cmd_cleanup_async_ctx should return only after all its callback
handlers were completed. Before this patch, the below race between
mlx5_cmd_cleanup_async_ctx and mlx5_cmd_exec_cb_handler was possible and
lead to a use-after-free:

1. mlx5_cmd_cleanup_async_ctx is called while num_inflight is 2 (i.e.
   elevated by 1, a single inflight callback).
2. mlx5_cmd_cleanup_async_ctx decreases num_inflight to 1.
3. mlx5_cmd_exec_cb_handler is called, decreases num_inflight to 0 and
   is about to call wake_up().
4. mlx5_cmd_cleanup_async_ctx calls wait_event, which returns
   immediately as the condition (num_inflight == 0) holds.
5. mlx5_cmd_cleanup_async_ctx returns.
6. The caller of mlx5_cmd_cleanup_async_ctx frees the mlx5_async_ctx
   object.
7. mlx5_cmd_exec_cb_handler goes on and calls wake_up() on the freed
   object.

Fix it by syncing using a completion object. Mark it completed when
num_inflight reaches 0.

Trace:

BUG: KASAN: use-after-free in do_raw_spin_lock+0x23d/0x270
Read of size 4 at addr ffff888139cd12f4 by task swapper/5/0

CPU: 5 PID: 0 Comm: swapper/5 Not tainted 6.0.0-rc3_for_upstream_debug_2022_08_30_13_10 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
 &lt;IRQ&gt;
 dump_stack_lvl+0x57/0x7d
 print_report.cold+0x2d5/0x684
 ? do_raw_spin_lock+0x23d/0x270
 kasan_report+0xb1/0x1a0
 ? do_raw_spin_lock+0x23d/0x270
 do_raw_spin_lock+0x23d/0x270
 ? rwlock_bug.part.0+0x90/0x90
 ? __delete_object+0xb8/0x100
 ? lock_downgrade+0x6e0/0x6e0
 _raw_spin_lock_irqsave+0x43/0x60
 ? __wake_up_common_lock+0xb9/0x140
 __wake_up_common_lock+0xb9/0x140
 ? __wake_up_common+0x650/0x650
 ? destroy_tis_callback+0x53/0x70 [mlx5_core]
 ? kasan_set_track+0x21/0x30
 ? destroy_tis_callback+0x53/0x70 [mlx5_core]
 ? kfree+0x1ba/0x520
 ? do_raw_spin_unlock+0x54/0x220
 mlx5_cmd_exec_cb_handler+0x136/0x1a0 [mlx5_core]
 ? mlx5_cmd_cleanup_async_ctx+0x220/0x220 [mlx5_core]
 ? mlx5_cmd_cleanup_async_ctx+0x220/0x220 [mlx5_core]
 mlx5_cmd_comp_handler+0x65a/0x12b0 [mlx5_core]
 ? dump_command+0xcc0/0xcc0 [mlx5_core]
 ? lockdep_hardirqs_on_prepare+0x400/0x400
 ? cmd_comp_notifier+0x7e/0xb0 [mlx5_core]
 cmd_comp_notifier+0x7e/0xb0 [mlx5_core]
 atomic_notifier_call_chain+0xd7/0x1d0
 mlx5_eq_async_int+0x3ce/0xa20 [mlx5_core]
 atomic_notifier_call_chain+0xd7/0x1d0
 ? irq_release+0x140/0x140 [mlx5_core]
 irq_int_handler+0x19/0x30 [mlx5_core]
 __handle_irq_event_percpu+0x1f2/0x620
 handle_irq_event+0xb2/0x1d0
 handle_edge_irq+0x21e/0xb00
 __common_interrupt+0x79/0x1a0
 common_interrupt+0x78/0xa0
 &lt;/IRQ&gt;
 &lt;TASK&gt;
 asm_common_interrupt+0x22/0x40
RIP: 0010:default_idle+0x42/0x60
Code: c1 83 e0 07 48 c1 e9 03 83 c0 03 0f b6 14 11 38 d0 7c 04 84 d2 75 14 8b 05 eb 47 22 02 85 c0 7e 07 0f 00 2d e0 9f 48 00 fb f4 &lt;c3&gt; 48 c7 c7 80 08 7f 85 e8 d1 d3 3e fe eb de 66 66 2e 0f 1f 84 00
RSP: 0018:ffff888100dbfdf0 EFLAGS: 00000242
RAX: 0000000000000001 RBX: ffffffff84ecbd48 RCX: 1ffffffff0afe110
RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffffffff835cc9bc
RBP: 0000000000000005 R08: 0000000000000001 R09: ffff88881dec4ac3
R10: ffffed1103bd8958 R11: 0000017d0ca571c9 R12: 0000000000000005
R13: ffffffff84f024e0 R14: 0000000000000000 R15: dffffc0000000000
 ? default_idle_call+0xcc/0x450
 default_idle_call+0xec/0x450
 do_idle+0x394/0x450
 ? arch_cpu_idle_exit+0x40/0x40
 ? do_idle+0x17/0x450
 cpu_startup_entry+0x19/0x20
 start_secondary+0x221/0x2b0
 ? set_cpu_sibling_map+0x2070/0x2070
 secondary_startup_64_no_verify+0xcd/0xdb
 &lt;/TASK&gt;

Allocated by task 49502:
 kasan_save_stack+0x1e/0x40
 __kasan_kmalloc+0x81/0xa0
 kvmalloc_node+0x48/0xe0
 mlx5e_bulk_async_init+0x35/0x110 [mlx5_core]
 mlx5e_tls_priv_tx_list_cleanup+0x84/0x3e0 [mlx5_core]
 mlx5e_ktls_cleanup_tx+0x38f/0x760 [mlx5_core]
 mlx5e_cleanup_nic_tx+0xa7/0x100 [mlx5_core]
 mlx5e_detach_netdev+0x1ca/0x2b0 [mlx5_core]
 mlx5e_suspend+0xdb/0x140 [mlx5_core]
 mlx5e_remove+0x89/0x190 [mlx5_core]
 auxiliary_bus_remove+0x52/0x70
 device_release_driver_internal+0x40f/0x650
 driver_detach+0xc1/0x180
 bus_remove_driver+0x125/0x2f0
 auxiliary_driver_unregister+0x16/0x50
 mlx5e_cleanup+0x26/0x30 [mlx5_core]
 cleanup+0xc/0x4e [mlx5_core]
 __x64_sys_delete_module+0x2b5/0x450
 do_syscall_64+0x3d/0x90
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

Freed by task 49502:
 kasan_save_stack+0x1e/0x40
 kasan_set_track+0x21/0x30
 kasan_set_free_info+0x20/0x30
 ____kasan_slab_free+0x11d/0x1b0
 kfree+0x1ba/0x520
 mlx5e_tls_priv_tx_list_cleanup+0x2e7/0x3e0 [mlx5_core]
 mlx5e_ktls_cleanup_tx+0x38f/0x760 [mlx5_core]
 mlx5e_cleanup_nic_tx+0xa7/0x100 [mlx5_core]
 mlx5e_detach_netdev+0x1ca/0x2b0 [mlx5_core]
 mlx5e_suspend+0xdb/0x140 [mlx5_core]
 mlx5e_remove+0x89/0x190 [mlx5_core]
 auxiliary_bus_remove+0x52/0x70
 device_release_driver_internal+0x40f/0x650
 driver_detach+0xc1/0x180
 bus_remove_driver+0x125/0x2f0
 auxiliary_driver_unregister+0x16/0x50
 mlx5e_cleanup+0x26/0x30 [mlx5_core]
 cleanup+0xc/0x4e [mlx5_core]
 __x64_sys_delete_module+0x2b5/0x450
 do_syscall_64+0x3d/0x90
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

Fixes: e355477ed9e4 ("net/mlx5: Make mlx5_cmd_exec_cb() a safe API")
Signed-off-by: Tariq Toukan &lt;tariqt@nvidia.com&gt;
Reviewed-by: Moshe Shemesh &lt;moshe@nvidia.com&gt;
Signed-off-by: Saeed Mahameed &lt;saeedm@nvidia.com&gt;
Link: https://lore.kernel.org/r/20221026135153.154807-8-saeed@kernel.org
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 bacd22df95147ed673bec4692ab2d4d585935241 ]

mlx5_cmd_cleanup_async_ctx should return only after all its callback
handlers were completed. Before this patch, the below race between
mlx5_cmd_cleanup_async_ctx and mlx5_cmd_exec_cb_handler was possible and
lead to a use-after-free:

1. mlx5_cmd_cleanup_async_ctx is called while num_inflight is 2 (i.e.
   elevated by 1, a single inflight callback).
2. mlx5_cmd_cleanup_async_ctx decreases num_inflight to 1.
3. mlx5_cmd_exec_cb_handler is called, decreases num_inflight to 0 and
   is about to call wake_up().
4. mlx5_cmd_cleanup_async_ctx calls wait_event, which returns
   immediately as the condition (num_inflight == 0) holds.
5. mlx5_cmd_cleanup_async_ctx returns.
6. The caller of mlx5_cmd_cleanup_async_ctx frees the mlx5_async_ctx
   object.
7. mlx5_cmd_exec_cb_handler goes on and calls wake_up() on the freed
   object.

Fix it by syncing using a completion object. Mark it completed when
num_inflight reaches 0.

Trace:

BUG: KASAN: use-after-free in do_raw_spin_lock+0x23d/0x270
Read of size 4 at addr ffff888139cd12f4 by task swapper/5/0

CPU: 5 PID: 0 Comm: swapper/5 Not tainted 6.0.0-rc3_for_upstream_debug_2022_08_30_13_10 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
 &lt;IRQ&gt;
 dump_stack_lvl+0x57/0x7d
 print_report.cold+0x2d5/0x684
 ? do_raw_spin_lock+0x23d/0x270
 kasan_report+0xb1/0x1a0
 ? do_raw_spin_lock+0x23d/0x270
 do_raw_spin_lock+0x23d/0x270
 ? rwlock_bug.part.0+0x90/0x90
 ? __delete_object+0xb8/0x100
 ? lock_downgrade+0x6e0/0x6e0
 _raw_spin_lock_irqsave+0x43/0x60
 ? __wake_up_common_lock+0xb9/0x140
 __wake_up_common_lock+0xb9/0x140
 ? __wake_up_common+0x650/0x650
 ? destroy_tis_callback+0x53/0x70 [mlx5_core]
 ? kasan_set_track+0x21/0x30
 ? destroy_tis_callback+0x53/0x70 [mlx5_core]
 ? kfree+0x1ba/0x520
 ? do_raw_spin_unlock+0x54/0x220
 mlx5_cmd_exec_cb_handler+0x136/0x1a0 [mlx5_core]
 ? mlx5_cmd_cleanup_async_ctx+0x220/0x220 [mlx5_core]
 ? mlx5_cmd_cleanup_async_ctx+0x220/0x220 [mlx5_core]
 mlx5_cmd_comp_handler+0x65a/0x12b0 [mlx5_core]
 ? dump_command+0xcc0/0xcc0 [mlx5_core]
 ? lockdep_hardirqs_on_prepare+0x400/0x400
 ? cmd_comp_notifier+0x7e/0xb0 [mlx5_core]
 cmd_comp_notifier+0x7e/0xb0 [mlx5_core]
 atomic_notifier_call_chain+0xd7/0x1d0
 mlx5_eq_async_int+0x3ce/0xa20 [mlx5_core]
 atomic_notifier_call_chain+0xd7/0x1d0
 ? irq_release+0x140/0x140 [mlx5_core]
 irq_int_handler+0x19/0x30 [mlx5_core]
 __handle_irq_event_percpu+0x1f2/0x620
 handle_irq_event+0xb2/0x1d0
 handle_edge_irq+0x21e/0xb00
 __common_interrupt+0x79/0x1a0
 common_interrupt+0x78/0xa0
 &lt;/IRQ&gt;
 &lt;TASK&gt;
 asm_common_interrupt+0x22/0x40
RIP: 0010:default_idle+0x42/0x60
Code: c1 83 e0 07 48 c1 e9 03 83 c0 03 0f b6 14 11 38 d0 7c 04 84 d2 75 14 8b 05 eb 47 22 02 85 c0 7e 07 0f 00 2d e0 9f 48 00 fb f4 &lt;c3&gt; 48 c7 c7 80 08 7f 85 e8 d1 d3 3e fe eb de 66 66 2e 0f 1f 84 00
RSP: 0018:ffff888100dbfdf0 EFLAGS: 00000242
RAX: 0000000000000001 RBX: ffffffff84ecbd48 RCX: 1ffffffff0afe110
RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffffffff835cc9bc
RBP: 0000000000000005 R08: 0000000000000001 R09: ffff88881dec4ac3
R10: ffffed1103bd8958 R11: 0000017d0ca571c9 R12: 0000000000000005
R13: ffffffff84f024e0 R14: 0000000000000000 R15: dffffc0000000000
 ? default_idle_call+0xcc/0x450
 default_idle_call+0xec/0x450
 do_idle+0x394/0x450
 ? arch_cpu_idle_exit+0x40/0x40
 ? do_idle+0x17/0x450
 cpu_startup_entry+0x19/0x20
 start_secondary+0x221/0x2b0
 ? set_cpu_sibling_map+0x2070/0x2070
 secondary_startup_64_no_verify+0xcd/0xdb
 &lt;/TASK&gt;

Allocated by task 49502:
 kasan_save_stack+0x1e/0x40
 __kasan_kmalloc+0x81/0xa0
 kvmalloc_node+0x48/0xe0
 mlx5e_bulk_async_init+0x35/0x110 [mlx5_core]
 mlx5e_tls_priv_tx_list_cleanup+0x84/0x3e0 [mlx5_core]
 mlx5e_ktls_cleanup_tx+0x38f/0x760 [mlx5_core]
 mlx5e_cleanup_nic_tx+0xa7/0x100 [mlx5_core]
 mlx5e_detach_netdev+0x1ca/0x2b0 [mlx5_core]
 mlx5e_suspend+0xdb/0x140 [mlx5_core]
 mlx5e_remove+0x89/0x190 [mlx5_core]
 auxiliary_bus_remove+0x52/0x70
 device_release_driver_internal+0x40f/0x650
 driver_detach+0xc1/0x180
 bus_remove_driver+0x125/0x2f0
 auxiliary_driver_unregister+0x16/0x50
 mlx5e_cleanup+0x26/0x30 [mlx5_core]
 cleanup+0xc/0x4e [mlx5_core]
 __x64_sys_delete_module+0x2b5/0x450
 do_syscall_64+0x3d/0x90
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

Freed by task 49502:
 kasan_save_stack+0x1e/0x40
 kasan_set_track+0x21/0x30
 kasan_set_free_info+0x20/0x30
 ____kasan_slab_free+0x11d/0x1b0
 kfree+0x1ba/0x520
 mlx5e_tls_priv_tx_list_cleanup+0x2e7/0x3e0 [mlx5_core]
 mlx5e_ktls_cleanup_tx+0x38f/0x760 [mlx5_core]
 mlx5e_cleanup_nic_tx+0xa7/0x100 [mlx5_core]
 mlx5e_detach_netdev+0x1ca/0x2b0 [mlx5_core]
 mlx5e_suspend+0xdb/0x140 [mlx5_core]
 mlx5e_remove+0x89/0x190 [mlx5_core]
 auxiliary_bus_remove+0x52/0x70
 device_release_driver_internal+0x40f/0x650
 driver_detach+0xc1/0x180
 bus_remove_driver+0x125/0x2f0
 auxiliary_driver_unregister+0x16/0x50
 mlx5e_cleanup+0x26/0x30 [mlx5_core]
 cleanup+0xc/0x4e [mlx5_core]
 __x64_sys_delete_module+0x2b5/0x450
 do_syscall_64+0x3d/0x90
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

Fixes: e355477ed9e4 ("net/mlx5: Make mlx5_cmd_exec_cb() a safe API")
Signed-off-by: Tariq Toukan &lt;tariqt@nvidia.com&gt;
Reviewed-by: Moshe Shemesh &lt;moshe@nvidia.com&gt;
Signed-off-by: Saeed Mahameed &lt;saeedm@nvidia.com&gt;
Link: https://lore.kernel.org/r/20221026135153.154807-8-saeed@kernel.org
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>media: videodev2.h: V4L2_DV_BT_BLANKING_HEIGHT should check 'interlaced'</title>
<updated>2022-11-03T15:00:32+00:00</updated>
<author>
<name>Hans Verkuil</name>
<email>hverkuil-cisco@xs4all.nl</email>
</author>
<published>2022-10-12T15:46:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=648d545c12134cafa7b80968fbf948329bf89f16'/>
<id>648d545c12134cafa7b80968fbf948329bf89f16</id>
<content type='text'>
[ Upstream commit 8da7f0976b9071b528c545008de9d10cc81883b1 ]

If it is a progressive (non-interlaced) format, then ignore the
interlaced timing values.

Signed-off-by: Hans Verkuil &lt;hverkuil-cisco@xs4all.nl&gt;
Fixes: 7f68127fa11f ([media] videodev2.h: defines to calculate blanking and frame sizes)
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab@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 8da7f0976b9071b528c545008de9d10cc81883b1 ]

If it is a progressive (non-interlaced) format, then ignore the
interlaced timing values.

Signed-off-by: Hans Verkuil &lt;hverkuil-cisco@xs4all.nl&gt;
Fixes: 7f68127fa11f ([media] videodev2.h: defines to calculate blanking and frame sizes)
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net-memcg: avoid stalls when under memory pressure</title>
<updated>2022-11-03T15:00:31+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2022-10-21T16:03:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=568737b2829631927b6aed7308e37bc33a3bd3a4'/>
<id>568737b2829631927b6aed7308e37bc33a3bd3a4</id>
<content type='text'>
[ Upstream commit 720ca52bcef225b967a339e0fffb6d0c7e962240 ]

As Shakeel explains the commit under Fixes had the unintended
side-effect of no longer pre-loading the cached memory allowance.
Even tho we previously dropped the first packet received when
over memory limit - the consecutive ones would get thru by using
the cache. The charging was happening in batches of 128kB, so
we'd let in 128kB (truesize) worth of packets per one drop.

After the change we no longer force charge, there will be no
cache filling side effects. This causes significant drops and
connection stalls for workloads which use a lot of page cache,
since we can't reclaim page cache under GFP_NOWAIT.

Some of the latency can be recovered by improving SACK reneg
handling but nowhere near enough to get back to the pre-5.15
performance (the application I'm experimenting with still
sees 5-10x worst latency).

Apply the suggested workaround of using GFP_ATOMIC. We will now
be more permissive than previously as we'll drop _no_ packets
in softirq when under pressure. But I can't think of any good
and simple way to address that within networking.

Link: https://lore.kernel.org/all/20221012163300.795e7b86@kernel.org/
Suggested-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Fixes: 4b1327be9fe5 ("net-memcg: pass in gfp_t mask to mem_cgroup_charge_skmem()")
Acked-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Acked-by: Roman Gushchin &lt;roman.gushchin@linux.dev&gt;
Link: https://lore.kernel.org/r/20221021160304.1362511-1-kuba@kernel.org
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 720ca52bcef225b967a339e0fffb6d0c7e962240 ]

As Shakeel explains the commit under Fixes had the unintended
side-effect of no longer pre-loading the cached memory allowance.
Even tho we previously dropped the first packet received when
over memory limit - the consecutive ones would get thru by using
the cache. The charging was happening in batches of 128kB, so
we'd let in 128kB (truesize) worth of packets per one drop.

After the change we no longer force charge, there will be no
cache filling side effects. This causes significant drops and
connection stalls for workloads which use a lot of page cache,
since we can't reclaim page cache under GFP_NOWAIT.

Some of the latency can be recovered by improving SACK reneg
handling but nowhere near enough to get back to the pre-5.15
performance (the application I'm experimenting with still
sees 5-10x worst latency).

Apply the suggested workaround of using GFP_ATOMIC. We will now
be more permissive than previously as we'll drop _no_ packets
in softirq when under pressure. But I can't think of any good
and simple way to address that within networking.

Link: https://lore.kernel.org/all/20221012163300.795e7b86@kernel.org/
Suggested-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Fixes: 4b1327be9fe5 ("net-memcg: pass in gfp_t mask to mem_cgroup_charge_skmem()")
Acked-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Acked-by: Roman Gushchin &lt;roman.gushchin@linux.dev&gt;
Link: https://lore.kernel.org/r/20221021160304.1362511-1-kuba@kernel.org
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>ASoC: Intel: common: add ACPI matching tables for Raptor Lake</title>
<updated>2022-11-03T15:00:28+00:00</updated>
<author>
<name>Kai Vehmanen</name>
<email>kai.vehmanen@linux.intel.com</email>
</author>
<published>2022-08-16T13:05:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dde19797bdf37432a87fe0753f9e85baa146a757'/>
<id>dde19797bdf37432a87fe0753f9e85baa146a757</id>
<content type='text'>
[ Upstream commit 5f3db54cfbc21772d984372fdcc5bb17b57f425f ]

Initial support for RPL w/ RT711

Signed-off-by: Kai Vehmanen &lt;kai.vehmanen@linux.intel.com&gt;
Reviewed-by: Bard Liao &lt;yung-chuan.liao@linux.intel.com&gt;
Reviewed-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Tested-by: Gopal Vamshi Krishna &lt;vamshi.krishna.gopal@intel.com&gt;
Link: https://lore.kernel.org/r/20220816130510.190427-1-kai.vehmanen@linux.intel.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Stable-dep-of: 05de5cf6fb7d ("ASoC: SOF: Intel: pci-tgl: fix ADL-N descriptor")
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 5f3db54cfbc21772d984372fdcc5bb17b57f425f ]

Initial support for RPL w/ RT711

Signed-off-by: Kai Vehmanen &lt;kai.vehmanen@linux.intel.com&gt;
Reviewed-by: Bard Liao &lt;yung-chuan.liao@linux.intel.com&gt;
Reviewed-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Tested-by: Gopal Vamshi Krishna &lt;vamshi.krishna.gopal@intel.com&gt;
Link: https://lore.kernel.org/r/20220816130510.190427-1-kai.vehmanen@linux.intel.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Stable-dep-of: 05de5cf6fb7d ("ASoC: SOF: Intel: pci-tgl: fix ADL-N descriptor")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf: Fix missing SIGTRAPs</title>
<updated>2022-11-03T15:00:27+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2022-10-06T13:00:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=078c12ccf1fb943cc18c84894c76113dc89e5975'/>
<id>078c12ccf1fb943cc18c84894c76113dc89e5975</id>
<content type='text'>
[ Upstream commit ca6c21327c6af02b7eec31ce4b9a740a18c6c13f ]

Marco reported:

Due to the implementation of how SIGTRAP are delivered if
perf_event_attr::sigtrap is set, we've noticed 3 issues:

  1. Missing SIGTRAP due to a race with event_sched_out() (more
     details below).

  2. Hardware PMU events being disabled due to returning 1 from
     perf_event_overflow(). The only way to re-enable the event is
     for user space to first "properly" disable the event and then
     re-enable it.

  3. The inability to automatically disable an event after a
     specified number of overflows via PERF_EVENT_IOC_REFRESH.

The worst of the 3 issues is problem (1), which occurs when a
pending_disable is "consumed" by a racing event_sched_out(), observed
as follows:

		CPU0			|	CPU1
	--------------------------------+---------------------------
	__perf_event_overflow()		|
	 perf_event_disable_inatomic()	|
	  pending_disable = CPU0	| ...
					| _perf_event_enable()
					|  event_function_call()
					|   task_function_call()
					|    /* sends IPI to CPU0 */
	&lt;IPI&gt;				| ...
	 __perf_event_enable()		+---------------------------
	  ctx_resched()
	   task_ctx_sched_out()
	    ctx_sched_out()
	     group_sched_out()
	      event_sched_out()
	       pending_disable = -1
	&lt;/IPI&gt;
	&lt;IRQ-work&gt;
	 perf_pending_event()
	  perf_pending_event_disable()
	   /* Fails to send SIGTRAP because no pending_disable! */
	&lt;/IRQ-work&gt;

In the above case, not only is that particular SIGTRAP missed, but also
all future SIGTRAPs because 'event_limit' is not reset back to 1.

To fix, rework pending delivery of SIGTRAP via IRQ-work by introduction
of a separate 'pending_sigtrap', no longer using 'event_limit' and
'pending_disable' for its delivery.

Additionally; and different to Marco's proposed patch:

 - recognise that pending_disable effectively duplicates oncpu for
   the case where it is set. As such, change the irq_work handler to
   use -&gt;oncpu to target the event and use pending_* as boolean toggles.

 - observe that SIGTRAP targets the ctx-&gt;task, so the context switch
   optimization that carries contexts between tasks is invalid. If
   the irq_work were delayed enough to hit after a context switch the
   SIGTRAP would be delivered to the wrong task.

 - observe that if the event gets scheduled out
   (rotation/migration/context-switch/...) the irq-work would be
   insufficient to deliver the SIGTRAP when the event gets scheduled
   back in (the irq-work might still be pending on the old CPU).

   Therefore have event_sched_out() convert the pending sigtrap into a
   task_work which will deliver the signal at return_to_user.

Fixes: 97ba62b27867 ("perf: Add support for SIGTRAP on perf events")
Reported-by: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Debugged-by: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Reported-by: Marco Elver &lt;elver@google.com&gt;
Debugged-by: Marco Elver &lt;elver@google.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Reviewed-by: Marco Elver &lt;elver@google.com&gt;
Tested-by: Marco Elver &lt;elver@google.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 ca6c21327c6af02b7eec31ce4b9a740a18c6c13f ]

Marco reported:

Due to the implementation of how SIGTRAP are delivered if
perf_event_attr::sigtrap is set, we've noticed 3 issues:

  1. Missing SIGTRAP due to a race with event_sched_out() (more
     details below).

  2. Hardware PMU events being disabled due to returning 1 from
     perf_event_overflow(). The only way to re-enable the event is
     for user space to first "properly" disable the event and then
     re-enable it.

  3. The inability to automatically disable an event after a
     specified number of overflows via PERF_EVENT_IOC_REFRESH.

The worst of the 3 issues is problem (1), which occurs when a
pending_disable is "consumed" by a racing event_sched_out(), observed
as follows:

		CPU0			|	CPU1
	--------------------------------+---------------------------
	__perf_event_overflow()		|
	 perf_event_disable_inatomic()	|
	  pending_disable = CPU0	| ...
					| _perf_event_enable()
					|  event_function_call()
					|   task_function_call()
					|    /* sends IPI to CPU0 */
	&lt;IPI&gt;				| ...
	 __perf_event_enable()		+---------------------------
	  ctx_resched()
	   task_ctx_sched_out()
	    ctx_sched_out()
	     group_sched_out()
	      event_sched_out()
	       pending_disable = -1
	&lt;/IPI&gt;
	&lt;IRQ-work&gt;
	 perf_pending_event()
	  perf_pending_event_disable()
	   /* Fails to send SIGTRAP because no pending_disable! */
	&lt;/IRQ-work&gt;

In the above case, not only is that particular SIGTRAP missed, but also
all future SIGTRAPs because 'event_limit' is not reset back to 1.

To fix, rework pending delivery of SIGTRAP via IRQ-work by introduction
of a separate 'pending_sigtrap', no longer using 'event_limit' and
'pending_disable' for its delivery.

Additionally; and different to Marco's proposed patch:

 - recognise that pending_disable effectively duplicates oncpu for
   the case where it is set. As such, change the irq_work handler to
   use -&gt;oncpu to target the event and use pending_* as boolean toggles.

 - observe that SIGTRAP targets the ctx-&gt;task, so the context switch
   optimization that carries contexts between tasks is invalid. If
   the irq_work were delayed enough to hit after a context switch the
   SIGTRAP would be delivered to the wrong task.

 - observe that if the event gets scheduled out
   (rotation/migration/context-switch/...) the irq-work would be
   insufficient to deliver the SIGTRAP when the event gets scheduled
   back in (the irq-work might still be pending on the old CPU).

   Therefore have event_sched_out() convert the pending sigtrap into a
   task_work which will deliver the signal at return_to_user.

Fixes: 97ba62b27867 ("perf: Add support for SIGTRAP on perf events")
Reported-by: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Debugged-by: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Reported-by: Marco Elver &lt;elver@google.com&gt;
Debugged-by: Marco Elver &lt;elver@google.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Reviewed-by: Marco Elver &lt;elver@google.com&gt;
Tested-by: Marco Elver &lt;elver@google.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>media: v4l2: Fix v4l2_i2c_subdev_set_name function documentation</title>
<updated>2022-11-03T15:00:25+00:00</updated>
<author>
<name>Alexander Stein</name>
<email>alexander.stein@ew.tq-group.com</email>
</author>
<published>2022-07-22T07:11:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cf4cae3929cf29a7534d7b4dc99c40516737bf06'/>
<id>cf4cae3929cf29a7534d7b4dc99c40516737bf06</id>
<content type='text'>
[ Upstream commit bb9ea2c31fa11b789ade4c3abcdda3c5370a76ab ]

The doc says the I²C device's name is used if devname is NULL, but
actually the I²C device driver's name is used.

Fixes: 0658293012af ("media: v4l: subdev: Add a function to set an I²C sub-device's name")
Signed-off-by: Alexander Stein &lt;alexander.stein@ew.tq-group.com&gt;
Signed-off-by: Sakari Ailus &lt;sakari.ailus@linux.intel.com&gt;
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab@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 bb9ea2c31fa11b789ade4c3abcdda3c5370a76ab ]

The doc says the I²C device's name is used if devname is NULL, but
actually the I²C device driver's name is used.

Fixes: 0658293012af ("media: v4l: subdev: Add a function to set an I²C sub-device's name")
Signed-off-by: Alexander Stein &lt;alexander.stein@ew.tq-group.com&gt;
Signed-off-by: Sakari Ailus &lt;sakari.ailus@linux.intel.com&gt;
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm/uffd: fix vma check on userfault for wp</title>
<updated>2022-11-03T15:00:23+00:00</updated>
<author>
<name>Peter Xu</name>
<email>peterx@redhat.com</email>
</author>
<published>2022-10-24T19:33:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d77f1fb83c0ec79d8038d4c5cd7e33f9fd08b389'/>
<id>d77f1fb83c0ec79d8038d4c5cd7e33f9fd08b389</id>
<content type='text'>
commit 67eae54bc227b30dedcce9db68b063ba1adb7838 upstream.

We used to have a report that pte-marker code can be reached even when
uffd-wp is not compiled in for file memories, here:

https://lore.kernel.org/all/YzeR+R6b4bwBlBHh@x1n/T/#u

I just got time to revisit this and found that the root cause is we simply
messed up with the vma check, so that for !PTE_MARKER_UFFD_WP system, we
will allow UFFDIO_REGISTER of MINOR &amp; WP upon shmem as the check was
wrong:

    if (vm_flags &amp; VM_UFFD_MINOR)
        return is_vm_hugetlb_page(vma) || vma_is_shmem(vma);

Where we'll allow anything to pass on shmem as long as minor mode is
requested.

Axel did it right when introducing minor mode but I messed it up in
b1f9e876862d when moving code around.  Fix it.

Link: https://lkml.kernel.org/r/20221024193336.1233616-1-peterx@redhat.com
Link: https://lkml.kernel.org/r/20221024193336.1233616-2-peterx@redhat.com
Fixes: b1f9e876862d ("mm/uffd: enable write protection for shmem &amp; hugetlbfs")
Signed-off-by: Peter Xu &lt;peterx@redhat.com&gt;
Cc: Axel Rasmussen &lt;axelrasmussen@google.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Nadav Amit &lt;nadav.amit@gmail.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.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 67eae54bc227b30dedcce9db68b063ba1adb7838 upstream.

We used to have a report that pte-marker code can be reached even when
uffd-wp is not compiled in for file memories, here:

https://lore.kernel.org/all/YzeR+R6b4bwBlBHh@x1n/T/#u

I just got time to revisit this and found that the root cause is we simply
messed up with the vma check, so that for !PTE_MARKER_UFFD_WP system, we
will allow UFFDIO_REGISTER of MINOR &amp; WP upon shmem as the check was
wrong:

    if (vm_flags &amp; VM_UFFD_MINOR)
        return is_vm_hugetlb_page(vma) || vma_is_shmem(vma);

Where we'll allow anything to pass on shmem as long as minor mode is
requested.

Axel did it right when introducing minor mode but I messed it up in
b1f9e876862d when moving code around.  Fix it.

Link: https://lkml.kernel.org/r/20221024193336.1233616-1-peterx@redhat.com
Link: https://lkml.kernel.org/r/20221024193336.1233616-2-peterx@redhat.com
Fixes: b1f9e876862d ("mm/uffd: enable write protection for shmem &amp; hugetlbfs")
Signed-off-by: Peter Xu &lt;peterx@redhat.com&gt;
Cc: Axel Rasmussen &lt;axelrasmussen@google.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Nadav Amit &lt;nadav.amit@gmail.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ALSA: control: add snd_ctl_rename()</title>
<updated>2022-11-03T15:00:17+00:00</updated>
<author>
<name>Maciej S. Szmigiero</name>
<email>maciej.szmigiero@oracle.com</email>
</author>
<published>2022-10-20T20:46:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=862678dfec33f8ff7d9e4ae2875028a9c97b543d'/>
<id>862678dfec33f8ff7d9e4ae2875028a9c97b543d</id>
<content type='text'>
commit 966f015fe4329199cc49084ee2886cfb626b34d3 upstream.

Add a snd_ctl_rename() function that takes care of updating the control
hash entries for callers that already have the relevant struct snd_kcontrol
at hand and hold the control write lock (or simply haven't registered the
card yet).

Fixes: c27e1efb61c5 ("ALSA: control: Use xarray for faster lookups")
Cc: stable@vger.kernel.org
Signed-off-by: Maciej S. Szmigiero &lt;maciej.szmigiero@oracle.com&gt;
Link: https://lore.kernel.org/r/4170b71117ea81357a4f7eb8410f7cde20836c70.1666296963.git.maciej.szmigiero@oracle.com
Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&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 966f015fe4329199cc49084ee2886cfb626b34d3 upstream.

Add a snd_ctl_rename() function that takes care of updating the control
hash entries for callers that already have the relevant struct snd_kcontrol
at hand and hold the control write lock (or simply haven't registered the
card yet).

Fixes: c27e1efb61c5 ("ALSA: control: Use xarray for faster lookups")
Cc: stable@vger.kernel.org
Signed-off-by: Maciej S. Szmigiero &lt;maciej.szmigiero@oracle.com&gt;
Link: https://lore.kernel.org/r/4170b71117ea81357a4f7eb8410f7cde20836c70.1666296963.git.maciej.szmigiero@oracle.com
Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: sched: delete duplicate cleanup of backlog and qlen</title>
<updated>2022-10-29T08:08:34+00:00</updated>
<author>
<name>Zhengchao Shao</name>
<email>shaozhengchao@huawei.com</email>
</author>
<published>2022-08-24T00:52:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3c23f9adda4ed31b074dfd4a4d86cbc5fe77f9e3'/>
<id>3c23f9adda4ed31b074dfd4a4d86cbc5fe77f9e3</id>
<content type='text'>
[ Upstream commit c19d893fbf3f2f8fa864ae39652c7fee939edde2 ]

qdisc_reset() is clearing qdisc-&gt;q.qlen and qdisc-&gt;qstats.backlog
_after_ calling qdisc-&gt;ops-&gt;reset. There is no need to clear them
again in the specific reset function.

Signed-off-by: Zhengchao Shao &lt;shaozhengchao@huawei.com&gt;
Link: https://lore.kernel.org/r/20220824005231.345727-1-shaozhengchao@huawei.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Stable-dep-of: 2a3fc78210b9 ("net: sched: sfb: fix null pointer access issue when sfb_init() fails")
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 c19d893fbf3f2f8fa864ae39652c7fee939edde2 ]

qdisc_reset() is clearing qdisc-&gt;q.qlen and qdisc-&gt;qstats.backlog
_after_ calling qdisc-&gt;ops-&gt;reset. There is no need to clear them
again in the specific reset function.

Signed-off-by: Zhengchao Shao &lt;shaozhengchao@huawei.com&gt;
Link: https://lore.kernel.org/r/20220824005231.345727-1-shaozhengchao@huawei.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Stable-dep-of: 2a3fc78210b9 ("net: sched: sfb: fix null pointer access issue when sfb_init() fails")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>udp: Update reuse-&gt;has_conns under reuseport_lock.</title>
<updated>2022-10-29T08:08:33+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-10-14T18:26:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1fb3a672317fba2a54f1bc8a6401235c6f11f883'/>
<id>1fb3a672317fba2a54f1bc8a6401235c6f11f883</id>
<content type='text'>
[ Upstream commit 69421bf98482d089e50799f45e48b25ce4a8d154 ]

When we call connect() for a UDP socket in a reuseport group, we have
to update sk-&gt;sk_reuseport_cb-&gt;has_conns to 1.  Otherwise, the kernel
could select a unconnected socket wrongly for packets sent to the
connected socket.

However, the current way to set has_conns is illegal and possible to
trigger that problem.  reuseport_has_conns() changes has_conns under
rcu_read_lock(), which upgrades the RCU reader to the updater.  Then,
it must do the update under the updater's lock, reuseport_lock, but
it doesn't for now.

For this reason, there is a race below where we fail to set has_conns
resulting in the wrong socket selection.  To avoid the race, let's split
the reader and updater with proper locking.

 cpu1                               cpu2
+----+                             +----+

__ip[46]_datagram_connect()        reuseport_grow()
.                                  .
|- reuseport_has_conns(sk, true)   |- more_reuse = __reuseport_alloc(more_socks_size)
|  .                               |
|  |- rcu_read_lock()
|  |- reuse = rcu_dereference(sk-&gt;sk_reuseport_cb)
|  |
|  |                               |  /* reuse-&gt;has_conns == 0 here */
|  |                               |- more_reuse-&gt;has_conns = reuse-&gt;has_conns
|  |- reuse-&gt;has_conns = 1         |  /* more_reuse-&gt;has_conns SHOULD BE 1 HERE */
|  |                               |
|  |                               |- rcu_assign_pointer(reuse-&gt;socks[i]-&gt;sk_reuseport_cb,
|  |                               |                     more_reuse)
|  `- rcu_read_unlock()            `- kfree_rcu(reuse, rcu)
|
|- sk-&gt;sk_state = TCP_ESTABLISHED

Note the likely(reuse) in reuseport_has_conns_set() is always true,
but we put the test there for ease of review.  [0]

For the record, usually, sk_reuseport_cb is changed under lock_sock().
The only exception is reuseport_grow() &amp; TCP reqsk migration case.

  1) shutdown() TCP listener, which is moved into the latter part of
     reuse-&gt;socks[] to migrate reqsk.

  2) New listen() overflows reuse-&gt;socks[] and call reuseport_grow().

  3) reuse-&gt;max_socks overflows u16 with the new listener.

  4) reuseport_grow() pops the old shutdown()ed listener from the array
     and update its sk-&gt;sk_reuseport_cb as NULL without lock_sock().

shutdown()ed TCP sk-&gt;sk_reuseport_cb can be changed without lock_sock(),
but, reuseport_has_conns_set() is called only for UDP under lock_sock(),
so likely(reuse) never be false in reuseport_has_conns_set().

[0]: https://lore.kernel.org/netdev/CANn89iLja=eQHbsM_Ta2sQF0tOGU8vAGrh_izRuuHjuO1ouUag@mail.gmail.com/

Fixes: acdcecc61285 ("udp: correct reuseport selection with connected sockets")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Link: https://lore.kernel.org/r/20221014182625.89913-1-kuniyu@amazon.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'>
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[ Upstream commit 69421bf98482d089e50799f45e48b25ce4a8d154 ]

When we call connect() for a UDP socket in a reuseport group, we have
to update sk-&gt;sk_reuseport_cb-&gt;has_conns to 1.  Otherwise, the kernel
could select a unconnected socket wrongly for packets sent to the
connected socket.

However, the current way to set has_conns is illegal and possible to
trigger that problem.  reuseport_has_conns() changes has_conns under
rcu_read_lock(), which upgrades the RCU reader to the updater.  Then,
it must do the update under the updater's lock, reuseport_lock, but
it doesn't for now.

For this reason, there is a race below where we fail to set has_conns
resulting in the wrong socket selection.  To avoid the race, let's split
the reader and updater with proper locking.

 cpu1                               cpu2
+----+                             +----+

__ip[46]_datagram_connect()        reuseport_grow()
.                                  .
|- reuseport_has_conns(sk, true)   |- more_reuse = __reuseport_alloc(more_socks_size)
|  .                               |
|  |- rcu_read_lock()
|  |- reuse = rcu_dereference(sk-&gt;sk_reuseport_cb)
|  |
|  |                               |  /* reuse-&gt;has_conns == 0 here */
|  |                               |- more_reuse-&gt;has_conns = reuse-&gt;has_conns
|  |- reuse-&gt;has_conns = 1         |  /* more_reuse-&gt;has_conns SHOULD BE 1 HERE */
|  |                               |
|  |                               |- rcu_assign_pointer(reuse-&gt;socks[i]-&gt;sk_reuseport_cb,
|  |                               |                     more_reuse)
|  `- rcu_read_unlock()            `- kfree_rcu(reuse, rcu)
|
|- sk-&gt;sk_state = TCP_ESTABLISHED

Note the likely(reuse) in reuseport_has_conns_set() is always true,
but we put the test there for ease of review.  [0]

For the record, usually, sk_reuseport_cb is changed under lock_sock().
The only exception is reuseport_grow() &amp; TCP reqsk migration case.

  1) shutdown() TCP listener, which is moved into the latter part of
     reuse-&gt;socks[] to migrate reqsk.

  2) New listen() overflows reuse-&gt;socks[] and call reuseport_grow().

  3) reuse-&gt;max_socks overflows u16 with the new listener.

  4) reuseport_grow() pops the old shutdown()ed listener from the array
     and update its sk-&gt;sk_reuseport_cb as NULL without lock_sock().

shutdown()ed TCP sk-&gt;sk_reuseport_cb can be changed without lock_sock(),
but, reuseport_has_conns_set() is called only for UDP under lock_sock(),
so likely(reuse) never be false in reuseport_has_conns_set().

[0]: https://lore.kernel.org/netdev/CANn89iLja=eQHbsM_Ta2sQF0tOGU8vAGrh_izRuuHjuO1ouUag@mail.gmail.com/

Fixes: acdcecc61285 ("udp: correct reuseport selection with connected sockets")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Link: https://lore.kernel.org/r/20221014182625.89913-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
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