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160,408 commits

Author SHA1 Message Date
Chris Down
cca34a0a76 Bluetooth: hci_event: Mask data status from LE ext adv reports
[ Upstream commit 0cadf8534f ]

The Event_Type field in an LE Extended Advertising Report uses bits 5
and 6 for data status (e.g. truncation or fragmentation), not the PDU
type itself.

The ext_evt_type_to_legacy() function fails to mask these status bits
before evaluation. This causes valid advertisements with status bits set
(e.g. a truncated non-connectable advertisement, which ends up showing
as PDU type 0x40) to be misclassified as unknown and subsequently
dropped. This is okay for most checks which use bitwise AND on the
relevant event type bits, but it doesn't work for non-connectable types,
which are checked with '== LE_EXT_ADV_NON_CONN_IND' (that is, zero).

In terms of behaviour, first the device sends a truncated report:

> HCI Event: LE Meta Event (0x3e) plen 26
      LE Extended Advertising Report (0x0d)
        Entry 0
          Event type: 0x0040
            Data status: Incomplete, data truncated, no more to come
          Address type: Random (0x01)
          Address: 1D:12:46:FA:F8:6E (Non-Resolvable)
          SID: 0x03
          RSSI: -98 dBm (0x9e)
          Data length: 0x00

Then, a few seconds later, it sends the subsequent complete report:

> HCI Event: LE Meta Event (0x3e) plen 122
      LE Extended Advertising Report (0x0d)
        Entry 0
          Event type: 0x0000
            Data status: Complete
          Address type: Random (0x01)
          Address: 1D:12:46:FA:F8:6E (Non-Resolvable)
          SID: 0x03
          RSSI: -97 dBm (0x9f)
          Data length: 0x60
          Service Data: Google (0xfef3)
            Data[92]: ...

These devices often send multiple truncated reports per second.

This patch introduces a PDU type mask to ensure only the relevant bits
are evaluated, allowing for the correct translation of all valid
extended advertising packets.

Fixes: b2cc9761f1 ("Bluetooth: Handle extended ADV PDU types")
Signed-off-by: Chris Down <chris@chrisdown.name>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:13:46 +02:00
Arseniy Krasnov
16852eccbd Bluetooth: hci_sync: fix double free in 'hci_discovery_filter_clear()'
[ Upstream commit 2935e55685 ]

Function 'hci_discovery_filter_clear()' frees 'uuids' array and then
sets it to NULL. There is a tiny chance of the following race:

'hci_cmd_sync_work()'

 'update_passive_scan_sync()'

   'hci_update_passive_scan_sync()'

     'hci_discovery_filter_clear()'
       kfree(uuids);

       <-------------------------preempted-------------------------------->
                                           'start_service_discovery()'

                                             'hci_discovery_filter_clear()'
                                               kfree(uuids); // DOUBLE FREE

       <-------------------------preempted-------------------------------->

      uuids = NULL;

To fix it let's add locking around 'kfree()' call and NULL pointer
assignment. Otherwise the following backtrace fires:

[ ] ------------[ cut here ]------------
[ ] kernel BUG at mm/slub.c:547!
[ ] Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
[ ] CPU: 3 UID: 0 PID: 246 Comm: bluetoothd Tainted: G O 6.12.19-kernel #1
[ ] Tainted: [O]=OOT_MODULE
[ ] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ ] pc : __slab_free+0xf8/0x348
[ ] lr : __slab_free+0x48/0x348
...
[ ] Call trace:
[ ]  __slab_free+0xf8/0x348
[ ]  kfree+0x164/0x27c
[ ]  start_service_discovery+0x1d0/0x2c0
[ ]  hci_sock_sendmsg+0x518/0x924
[ ]  __sock_sendmsg+0x54/0x60
[ ]  sock_write_iter+0x98/0xf8
[ ]  do_iter_readv_writev+0xe4/0x1c8
[ ]  vfs_writev+0x128/0x2b0
[ ]  do_writev+0xfc/0x118
[ ]  __arm64_sys_writev+0x20/0x2c
[ ]  invoke_syscall+0x68/0xf0
[ ]  el0_svc_common.constprop.0+0x40/0xe0
[ ]  do_el0_svc+0x1c/0x28
[ ]  el0_svc+0x30/0xd0
[ ]  el0t_64_sync_handler+0x100/0x12c
[ ]  el0t_64_sync+0x194/0x198
[ ] Code: 8b0002e6 eb17031f 54fffbe1 d503201f (d4210000)
[ ] ---[ end trace 0000000000000000 ]---

Fixes: ad383c2c65 ("Bluetooth: hci_sync: Enable advertising when LL privacy is enabled")
Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:13:46 +02:00
Steven Rostedt
5763daf5ca ring-buffer: Remove ring_buffer_read_prepare_sync()
[ Upstream commit 119a5d5736 ]

When the ring buffer was first introduced, reading the non-consuming
"trace" file required disabling the writing of the ring buffer. To make
sure the writing was fully disabled before iterating the buffer with a
non-consuming read, it would set the disable flag of the buffer and then
call an RCU synchronization to make sure all the buffers were
synchronized.

The function ring_buffer_read_start() originally  would initialize the
iterator and call an RCU synchronization, but this was for each individual
per CPU buffer where this would get called many times on a machine with
many CPUs before the trace file could be read. The commit 72c9ddfd4c
("ring-buffer: Make non-consuming read less expensive with lots of cpus.")
separated ring_buffer_read_start into ring_buffer_read_prepare(),
ring_buffer_read_sync() and then ring_buffer_read_start() to allow each of
the per CPU buffers to be prepared, call the read_buffer_read_sync() once,
and then the ring_buffer_read_start() for each of the CPUs which made
things much faster.

The commit 1039221cc2 ("ring-buffer: Do not disable recording when there
is an iterator") removed the requirement of disabling the recording of the
ring buffer in order to iterate it, but it did not remove the
synchronization that was happening that was required to wait for all the
buffers to have no more writers. It's now OK for the buffers to have
writers and no synchronization is needed.

Remove the synchronization and put back the interface for the ring buffer
iterator back before commit 72c9ddfd4c was applied.

Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250630180440.3eabb514@batman.local.home
Reported-by: David Howells <dhowells@redhat.com>
Fixes: 1039221cc2 ("ring-buffer: Do not disable recording when there is an iterator")
Tested-by: David Howells <dhowells@redhat.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:13:46 +02:00
Edward Srouji
19c262401e RDMA/mlx5: Fix UMR modifying of mkey page size
[ Upstream commit c4f96972c3 ]

When changing the page size on an mkey, the driver needs to set the
appropriate bits in the mkey mask to indicate which fields are being
modified.
The 6th bit of a page size in mlx5 driver is considered an extension,
and this bit has a dedicated capability and mask bits.

Previously, the driver was not setting this mask in the mkey mask when
performing page size changes, regardless of its hardware support,
potentially leading to an incorrect page size updates.

This fixes the issue by setting the relevant bit in the mkey mask when
performing page size changes on an mkey and the 6th bit of this field is
supported by the hardware.

Fixes: cef7dde883 ("net/mlx5: Expand mkey page size to support 6 bits")
Signed-off-by: Edward Srouji <edwards@nvidia.com>
Reviewed-by: Michael Guralnik <michaelgur@nvidia.com>
Link: https://patch.msgid.link/9f43a9c73bf2db6085a99dc836f7137e76579f09.1751979184.git.leon@kernel.org
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:13:43 +02:00
Eric Dumazet
bdb956891c net_sched: act_ctinfo: use atomic64_t for three counters
[ Upstream commit d300335b4e ]

Commit 21c167aa0b ("net/sched: act_ctinfo: use percpu stats")
missed that stats_dscp_set, stats_dscp_error and stats_cpmark_set
might be written (and read) locklessly.

Use atomic64_t for these three fields, I doubt act_ctinfo is used
heavily on big SMP hosts anyway.

Fixes: 24ec483cec ("net: sched: Introduce act_ctinfo action")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Pedro Tammela <pctammela@mojatatu.com>
Link: https://patch.msgid.link/20250709090204.797558-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:13:43 +02:00
Peter Zijlstra
c1cbee3aae sched/psi: Optimize psi_group_change() cpu_clock() usage
[ Upstream commit 570c8efd5e ]

Dietmar reported that commit 3840cbe24c ("sched: psi: fix bogus
pressure spikes from aggregation race") caused a regression for him on
a high context switch rate benchmark (schbench) due to the now
repeating cpu_clock() calls.

In particular the problem is that get_recent_times() will extrapolate
the current state to 'now'. But if an update uses a timestamp from
before the start of the update, it is possible to get two reads
with inconsistent results. It is effectively back-dating an update.

(note that this all hard-relies on the clock being synchronized across
CPUs -- if this is not the case, all bets are off).

Combine this problem with the fact that there are per-group-per-cpu
seqcounts, the commit in question pushed the clock read into the group
iteration, causing tree-depth cpu_clock() calls. On architectures
where cpu_clock() has appreciable overhead, this hurts.

Instead move to a per-cpu seqcount, which allows us to have a single
clock read for all group updates, increasing internal consistency and
lowering update overhead. This comes at the cost of a longer update
side (proportional to the tree depth) which can cause the read side to
retry more often.

Fixes: 3840cbe24c ("sched: psi: fix bogus pressure spikes from aggregation race")
Reported-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>,
Link: https://lkml.kernel.org/20250522084844.GC31726@noisy.programming.kicks-ass.net
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:13:42 +02:00
Eric Dumazet
939135ddea net: dst: annotate data-races around dst->output
[ Upstream commit 2dce8c52a9 ]

dst_dev_put() can overwrite dst->output while other
cpus might read this field (for instance from dst_output())

Add READ_ONCE()/WRITE_ONCE() annotations to suppress
potential issues.

We will likely need RCU protection in the future.

Fixes: 4a6ce2b6f2 ("net: introduce a new function dst_dev_put()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250630121934.3399505-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:13:41 +02:00
Eric Dumazet
002bb5722d net: dst: annotate data-races around dst->input
[ Upstream commit f1c5fd3489 ]

dst_dev_put() can overwrite dst->input while other
cpus might read this field (for instance from dst_input())

Add READ_ONCE()/WRITE_ONCE() annotations to suppress
potential issues.

We will likely need full RCU protection later.

Fixes: 4a6ce2b6f2 ("net: introduce a new function dst_dev_put()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250630121934.3399505-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:13:41 +02:00
Boris Brezillon
66d64d42d2 drm/panthor: Add missing explicit padding in drm_panthor_gpu_info
[ Upstream commit 95cbab4878 ]

drm_panthor_gpu_info::shader_present is currently automatically offset
by 4 byte to meet Arm's 32-bit/64-bit field alignment rules, but those
constraints don't stand on 32-bit x86 and cause a mismatch when running
an x86 binary in a user emulated environment like FEX. It's also
generally agreed that uAPIs should explicitly pad their struct fields,
which we originally intended to do, but a mistake slipped through during
the submission process, leading drm_panthor_gpu_info::shader_present to
be misaligned.

This uAPI change doesn't break any of the existing users of panthor
which are either arm32 or arm64 where the 64-bit alignment of
u64 fields is already enforced a the compiler level.

Changes in v2:
- Rename the garbage field into pad0 and adjust the comment accordingly
- Add Liviu's A-b

Changes in v3:
- Add R-bs

Fixes: 0f25e493a2 ("drm/panthor: Add uAPI")
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Adrián Larumbe <adrian.larumbe@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/20250606080932.4140010-2-boris.brezillon@collabora.com
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:13:39 +02:00
Denis OSTERLAND-HEIM
6ee761012d pps: fix poll support
[ Upstream commit 12c409aa1e ]

Because pps_cdev_poll() returns unconditionally EPOLLIN,
a user space program that calls select/poll get always an immediate data
ready-to-read response. As a result the intended use to wait until next
data becomes ready does not work.

User space snippet:

    struct pollfd pollfd = {
      .fd = open("/dev/pps0", O_RDONLY),
      .events = POLLIN|POLLERR,
      .revents = 0 };
    while(1) {
      poll(&pollfd, 1, 2000/*ms*/); // returns immediate, but should wait
      if(revents & EPOLLIN) { // always true
        struct pps_fdata fdata;
        memset(&fdata, 0, sizeof(memdata));
        ioctl(PPS_FETCH, &fdata); // currently fetches data at max speed
      }
    }

Lets remember the last fetch event counter and compare this value
in pps_cdev_poll() with most recent event counter
and return 0 if they are equal.

Signed-off-by: Denis OSTERLAND-HEIM <denis.osterland@diehl.com>
Co-developed-by: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Rodolfo Giometti <giometti@enneenne.com>
Fixes: eae9d2ba0c ("LinuxPPS: core support")
Link: https://lore.kernel.org/all/f6bed779-6d59-4f0f-8a59-b6312bd83b4e@enneenne.com/
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Link: https://lore.kernel.org/r/c3c50ad1eb19ef553eca8a57c17f4c006413ab70.camel@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:13:35 +02:00
RubenKelevra
47706f9acf fs_context: fix parameter name in infofc() macro
[ Upstream commit ffaf1bf373 ]

The macro takes a parameter called "p" but references "fc" internally.
This happens to compile as long as callers pass a variable named fc,
but breaks otherwise. Rename the first parameter to “fc” to match the
usage and to be consistent with warnfc() / errorfc().

Fixes: a3ff937b33 ("prefix-handling analogues of errorf() and friends")
Signed-off-by: RubenKelevra <rubenkelevra@gmail.com>
Link: https://lore.kernel.org/20250617230927.1790401-1-rubenkelevra@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:13:31 +02:00
Richard Guy Briggs
2f6c33b9fa audit,module: restore audit logging in load failure case
[ Upstream commit ae1ae11fb2 ]

The move of the module sanity check to earlier skipped the audit logging
call in the case of failure and to a place where the previously used
context is unavailable.

Add an audit logging call for the module loading failure case and get
the module name when possible.

Link: https://issues.redhat.com/browse/RHEL-52839
Fixes: 02da2cbab4 ("module: move check_modinfo() early to early_mod_check()")
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:13:31 +02:00
Stephen Rothwell
ba8e8a8a2e sprintf.h requires stdarg.h
commit 0dec720178 upstream.

In file included from drivers/crypto/intel/qat/qat_common/adf_pm_dbgfs_utils.c:4:
include/linux/sprintf.h:11:54: error: unknown type name 'va_list'
   11 | __printf(2, 0) int vsprintf(char *buf, const char *, va_list);
      |                                                      ^~~~~~~
include/linux/sprintf.h:1:1: note: 'va_list' is defined in header '<stdarg.h>'; this is probably fixable by adding '#include <stdarg.h>'

Link: https://lkml.kernel.org/r/20250721173754.42865913@canb.auug.org.au
Fixes: 39ced19b9e ("lib/vsprintf: split out sprintf() and friends")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Andriy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-08-01 09:48:43 +01:00
Arunpravin Paneer Selvam
198604687f drm/amdgpu: Reset the clear flag in buddy during resume
commit 95a16160ca upstream.

- Added a handler in DRM buddy manager to reset the cleared
  flag for the blocks in the freelist.

- This is necessary because, upon resuming, the VRAM becomes
  cluttered with BIOS data, yet the VRAM backend manager
  believes that everything has been cleared.

v2:
  - Add lock before accessing drm_buddy_clear_reset_blocks()(Matthew Auld)
  - Force merge the two dirty blocks.(Matthew Auld)
  - Add a new unit test case for this issue.(Matthew Auld)
  - Having this function being able to flip the state either way would be
    good. (Matthew Brost)

v3(Matthew Auld):
  - Do merge step first to avoid the use of extra reset flag.

Signed-off-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
Suggested-by: Christian König <christian.koenig@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Cc: stable@vger.kernel.org
Fixes: a68c7eaa7a ("drm/amdgpu: Enable clear page functionality")
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3812
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20250716075125.240637-2-Arunpravin.PaneerSelvam@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-08-01 09:48:42 +01:00
Halil Pasic
1194ad0d44 s390/ism: fix concurrency management in ism_cmd()
[ Upstream commit 897e8601b9 ]

The s390x ISM device data sheet clearly states that only one
request-response sequence is allowable per ISM function at any point in
time.  Unfortunately as of today the s390/ism driver in Linux does not
honor that requirement. This patch aims to rectify that.

This problem was discovered based on Aliaksei's bug report which states
that for certain workloads the ISM functions end up entering error state
(with PEC 2 as seen from the logs) after a while and as a consequence
connections handled by the respective function break, and for future
connection requests the ISM device is not considered -- given it is in a
dysfunctional state. During further debugging PEC 3A was observed as
well.

A kernel message like
[ 1211.244319] zpci: 061a:00:00.0: Event 0x2 reports an error for PCI function 0x61a
is a reliable indicator of the stated function entering error state
with PEC 2. Let me also point out that a kernel message like
[ 1211.244325] zpci: 061a:00:00.0: The ism driver bound to the device does not support error recovery
is a reliable indicator that the ISM function won't be auto-recovered
because the ISM driver currently lacks support for it.

On a technical level, without this synchronization, commands (inputs to
the FW) may be partially or fully overwritten (corrupted) by another CPU
trying to issue commands on the same function. There is hard evidence that
this can lead to DMB token values being used as DMB IOVAs, leading to
PEC 2 PCI events indicating invalid DMA. But this is only one of the
failure modes imaginable. In theory even completely losing one command
and executing another one twice and then trying to interpret the outputs
as if the command we intended to execute was actually executed and not
the other one is also possible.  Frankly, I don't feel confident about
providing an exhaustive list of possible consequences.

Fixes: 684b89bc39 ("s390/ism: add device driver for internal shared memory")
Reported-by: Aliaksei Makarau <Aliaksei.Makarau@ibm.com>
Tested-by: Mahanta Jambigi <mjambigi@linux.ibm.com>
Tested-by: Aliaksei Makarau <Aliaksei.Makarau@ibm.com>
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250722161817.1298473-1-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-01 09:48:42 +01:00
David Howells
839fe96c15 rxrpc: Fix recv-recv race of completed call
[ Upstream commit 962fb1f651 ]

If a call receives an event (such as incoming data), the call gets placed
on the socket's queue and a thread in recvmsg can be awakened to go and
process it.  Once the thread has picked up the call off of the queue,
further events will cause it to be requeued, and once the socket lock is
dropped (recvmsg uses call->user_mutex to allow the socket to be used in
parallel), a second thread can come in and its recvmsg can pop the call off
the socket queue again.

In such a case, the first thread will be receiving stuff from the call and
the second thread will be blocked on call->user_mutex.  The first thread
can, at this point, process both the event that it picked call for and the
event that the second thread picked the call for and may see the call
terminate - in which case the call will be "released", decoupling the call
from the user call ID assigned to it (RXRPC_USER_CALL_ID in the control
message).

The first thread will return okay, but then the second thread will wake up
holding the user_mutex and, if it sees that the call has been released by
the first thread, it will BUG thusly:

	kernel BUG at net/rxrpc/recvmsg.c:474!

Fix this by just dequeuing the call and ignoring it if it is seen to be
already released.  We can't tell userspace about it anyway as the user call
ID has become stale.

Fixes: 248f219cb8 ("rxrpc: Rewrite the data and ack handling code")
Reported-by: Junvyyang, Tencent Zhuque Lab <zhuque@tencent.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
cc: LePremierHomme <kwqcheii@proton.me>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
Link: https://patch.msgid.link/20250717074350.3767366-3-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-24 08:56:35 +02:00
Florian Westphal
fc38c249c6 netfilter: nf_conntrack: fix crash due to removal of uninitialised entry
[ Upstream commit 2d72afb340 ]

A crash in conntrack was reported while trying to unlink the conntrack
entry from the hash bucket list:
    [exception RIP: __nf_ct_delete_from_lists+172]
    [..]
 #7 [ff539b5a2b043aa0] nf_ct_delete at ffffffffc124d421 [nf_conntrack]
 #8 [ff539b5a2b043ad0] nf_ct_gc_expired at ffffffffc124d999 [nf_conntrack]
 #9 [ff539b5a2b043ae0] __nf_conntrack_find_get at ffffffffc124efbc [nf_conntrack]
    [..]

The nf_conn struct is marked as allocated from slab but appears to be in
a partially initialised state:

 ct hlist pointer is garbage; looks like the ct hash value
 (hence crash).
 ct->status is equal to IPS_CONFIRMED|IPS_DYING, which is expected
 ct->timeout is 30000 (=30s), which is unexpected.

Everything else looks like normal udp conntrack entry.  If we ignore
ct->status and pretend its 0, the entry matches those that are newly
allocated but not yet inserted into the hash:
  - ct hlist pointers are overloaded and store/cache the raw tuple hash
  - ct->timeout matches the relative time expected for a new udp flow
    rather than the absolute 'jiffies' value.

If it were not for the presence of IPS_CONFIRMED,
__nf_conntrack_find_get() would have skipped the entry.

Theory is that we did hit following race:

cpu x 			cpu y			cpu z
 found entry E		found entry E
 E is expired		<preemption>
 nf_ct_delete()
 return E to rcu slab
					init_conntrack
					E is re-inited,
					ct->status set to 0
					reply tuplehash hnnode.pprev
					stores hash value.

cpu y found E right before it was deleted on cpu x.
E is now re-inited on cpu z.  cpu y was preempted before
checking for expiry and/or confirm bit.

					->refcnt set to 1
					E now owned by skb
					->timeout set to 30000

If cpu y were to resume now, it would observe E as
expired but would skip E due to missing CONFIRMED bit.

					nf_conntrack_confirm gets called
					sets: ct->status |= CONFIRMED
					This is wrong: E is not yet added
					to hashtable.

cpu y resumes, it observes E as expired but CONFIRMED:
			<resumes>
			nf_ct_expired()
			 -> yes (ct->timeout is 30s)
			confirmed bit set.

cpu y will try to delete E from the hashtable:
			nf_ct_delete() -> set DYING bit
			__nf_ct_delete_from_lists

Even this scenario doesn't guarantee a crash:
cpu z still holds the table bucket lock(s) so y blocks:

			wait for spinlock held by z

					CONFIRMED is set but there is no
					guarantee ct will be added to hash:
					"chaintoolong" or "clash resolution"
					logic both skip the insert step.
					reply hnnode.pprev still stores the
					hash value.

					unlocks spinlock
					return NF_DROP
			<unblocks, then
			 crashes on hlist_nulls_del_rcu pprev>

In case CPU z does insert the entry into the hashtable, cpu y will unlink
E again right away but no crash occurs.

Without 'cpu y' race, 'garbage' hlist is of no consequence:
ct refcnt remains at 1, eventually skb will be free'd and E gets
destroyed via: nf_conntrack_put -> nf_conntrack_destroy -> nf_ct_destroy.

To resolve this, move the IPS_CONFIRMED assignment after the table
insertion but before the unlock.

Pablo points out that the confirm-bit-store could be reordered to happen
before hlist add resp. the timeout fixup, so switch to set_bit and
before_atomic memory barrier to prevent this.

It doesn't matter if other CPUs can observe a newly inserted entry right
before the CONFIRMED bit was set:

Such event cannot be distinguished from above "E is the old incarnation"
case: the entry will be skipped.

Also change nf_ct_should_gc() to first check the confirmed bit.

The gc sequence is:
 1. Check if entry has expired, if not skip to next entry
 2. Obtain a reference to the expired entry.
 3. Call nf_ct_should_gc() to double-check step 1.

nf_ct_should_gc() is thus called only for entries that already failed an
expiry check. After this patch, once the confirmed bit check passes
ct->timeout has been altered to reflect the absolute 'best before' date
instead of a relative time.  Step 3 will therefore not remove the entry.

Without this change to nf_ct_should_gc() we could still get this sequence:

 1. Check if entry has expired.
 2. Obtain a reference.
 3. Call nf_ct_should_gc() to double-check step 1:
    4 - entry is still observed as expired
    5 - meanwhile, ct->timeout is corrected to absolute value on other CPU
      and confirm bit gets set
    6 - confirm bit is seen
    7 - valid entry is removed again

First do check 6), then 4) so the gc expiry check always picks up either
confirmed bit unset (entry gets skipped) or expiry re-check failure for
re-inited conntrack objects.

This change cannot be backported to releases before 5.19. Without
commit 8a75a2c174 ("netfilter: conntrack: remove unconfirmed list")
|= IPS_CONFIRMED line cannot be moved without further changes.

Cc: Razvan Cojocaru <rzvncj@gmail.com>
Link: https://lore.kernel.org/netfilter-devel/20250627142758.25664-1-fw@strlen.de/
Link: https://lore.kernel.org/netfilter-devel/4239da15-83ff-4ca4-939d-faef283471bb@gmail.com/
Fixes: 1397af5bfd ("netfilter: conntrack: remove the percpu dying list")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-24 08:56:33 +02:00
Christian Eggers
f5a40e54cd Bluetooth: hci_core: add missing braces when using macro parameters
[ Upstream commit cdee6a4416 ]

Macro parameters should always be put into braces when accessing it.

Fixes: 4fc9857ab8 ("Bluetooth: hci_sync: Add check simultaneous roles support")
Signed-off-by: Christian Eggers <ceggers@arri.de>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-24 08:56:33 +02:00
Johannes Berg
d57dda2056 wifi: cfg80211: remove scan request n_channels counted_by
[ Upstream commit 444020f4bf ]

This reverts commit e3eac9f32e ("wifi: cfg80211: Annotate struct
cfg80211_scan_request with __counted_by").

This really has been a completely failed experiment. There were
no actual bugs found, and yet at this point we already have four
"fixes" to it, with nothing to show for but code churn, and it
never even made the code any safer.

In all of the cases that ended up getting "fixed", the structure
is also internally inconsistent after the n_channels setting as
the channel list isn't actually filled yet. You cannot scan with
such a structure, that's just wrong. In mac80211, the struct is
also reused multiple times, so initializing it once is no good.

Some previous "fixes" (e.g. one in brcm80211) are also just setting
n_channels before accessing the array, under the assumption that the
code is correct and the array can be accessed, further showing that
the whole thing is just pointless when the allocation count and use
count are not separate.

If we really wanted to fix it, we'd need to separately track the
number of channels allocated and the number of channels currently
used, but given that no bugs were found despite the numerous syzbot
reports, that'd just be a waste of time.

Remove the __counted_by() annotation. We really should also remove
a number of the n_channels settings that are setting up a structure
that's inconsistent, but that can wait.

Reported-by: syzbot+e834e757bd9b3d3e1251@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=e834e757bd9b3d3e1251
Fixes: e3eac9f32e ("wifi: cfg80211: Annotate struct cfg80211_scan_request with __counted_by")
Link: https://patch.msgid.link/20250714142130.9b0bbb7e1f07.I09112ccde72d445e11348fc2bef68942cb2ffc94@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-24 08:56:31 +02:00
Lukas Wunner
f2133b849f crypto: ecdsa - Harden against integer overflows in DIV_ROUND_UP()
commit b16510a530 upstream.

Herbert notes that DIV_ROUND_UP() may overflow unnecessarily if an ecdsa
implementation's ->key_size() callback returns an unusually large value.
Herbert instead suggests (for a division by 8):

  X / 8 + !!(X & 7)

Based on this formula, introduce a generic DIV_ROUND_UP_POW2() macro and
use it in lieu of DIV_ROUND_UP() for ->key_size() return values.

Additionally, use the macro in ecc_digits_from_bytes(), whose "nbytes"
parameter is a ->key_size() return value in some instances, or a
user-specified ASN.1 length in the case of ecdsa_get_signature_rs().

Link: https://lore.kernel.org/r/Z3iElsILmoSu6FuC@gondor.apana.org.au/
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-17 18:37:24 +02:00
Eric Dumazet
e0dd2e9729 netfilter: flowtable: account for Ethernet header in nf_flow_pppoe_proto()
[ Upstream commit 18cdb3d982 ]

syzbot found a potential access to uninit-value in nf_flow_pppoe_proto()

Blamed commit forgot the Ethernet header.

BUG: KMSAN: uninit-value in nf_flow_offload_inet_hook+0x7e4/0x940 net/netfilter/nf_flow_table_inet.c:27
  nf_flow_offload_inet_hook+0x7e4/0x940 net/netfilter/nf_flow_table_inet.c:27
  nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline]
  nf_hook_slow+0xe1/0x3d0 net/netfilter/core.c:623
  nf_hook_ingress include/linux/netfilter_netdev.h:34 [inline]
  nf_ingress net/core/dev.c:5742 [inline]
  __netif_receive_skb_core+0x4aff/0x70c0 net/core/dev.c:5837
  __netif_receive_skb_one_core net/core/dev.c:5975 [inline]
  __netif_receive_skb+0xcc/0xac0 net/core/dev.c:6090
  netif_receive_skb_internal net/core/dev.c:6176 [inline]
  netif_receive_skb+0x57/0x630 net/core/dev.c:6235
  tun_rx_batched+0x1df/0x980 drivers/net/tun.c:1485
  tun_get_user+0x4ee0/0x6b40 drivers/net/tun.c:1938
  tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1984
  new_sync_write fs/read_write.c:593 [inline]
  vfs_write+0xb4b/0x1580 fs/read_write.c:686
  ksys_write fs/read_write.c:738 [inline]
  __do_sys_write fs/read_write.c:749 [inline]

Reported-by: syzbot+bf6ed459397e307c3ad2@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/686bc073.a00a0220.c7b3.0086.GAE@google.com/T/#u
Fixes: 87b3593bed ("netfilter: flowtable: validate pppoe header")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Pablo Neira Ayuso <pablo@netfilter.org>
Link: https://patch.msgid.link/20250707124517.614489-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-17 18:37:18 +02:00
Gao Xiang
ea2350dfa3 erofs: refine readahead tracepoint
[ Upstream commit 4eb56b0761 ]

 - trace_erofs_readpages => trace_erofs_readahead;

 - Rename a redundant statement `nrpages = readahead_count(rac);`;

 - Move the tracepoint to the beginning of z_erofs_readahead().

Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Hongbo Li <lihongbo22@huawei.com>
Link: https://lore.kernel.org/r/20250514120820.2739288-1-hsiangkao@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Stable-dep-of: d53238b614 ("erofs: fix to add missing tracepoint in erofs_readahead()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-17 18:37:18 +02:00
Lachlan Hodges
d4a7056ca9 wifi: mac80211: correctly identify S1G short beacon
[ Upstream commit c5fd399a24 ]

mac80211 identifies a short beacon by the presence of the next
TBTT field, however the standard actually doesn't explicitly state that
the next TBTT can't be in a long beacon or even that it is required in
a short beacon - and as a result this validation does not work for all
vendor implementations.

The standard explicitly states that an S1G long beacon shall contain
the S1G beacon compatibility element as the first element in a beacon
transmitted at a TBTT that is not a TSBTT (Target Short Beacon
Transmission Time) as per IEEE80211-2024 11.1.3.10.1. This is validated
by 9.3.4.3 Table 9-76 which states that the S1G beacon compatibility
element is only allowed in the full set and is not allowed in the
minimum set of elements permitted for use within short beacons.

Correctly identify short beacons by the lack of an S1G beacon
compatibility element as the first element in an S1G beacon frame.

Fixes: 9eaffe5078 ("cfg80211: convert S1G beacon to scan results")
Signed-off-by: Simon Wadsworth <simon@morsemicro.com>
Signed-off-by: Lachlan Hodges <lachlan.hodges@morsemicro.com>
Link: https://patch.msgid.link/20250701075541.162619-1-lachlan.hodges@morsemicro.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-17 18:37:16 +02:00
Baolin Wang
ee6c677ef3 mm: fix the inaccurate memory statistics issue for users
commit 82241a83cd upstream.

On some large machines with a high number of CPUs running a 64K pagesize
kernel, we found that the 'RES' field is always 0 displayed by the top
command for some processes, which will cause a lot of confusion for users.

    PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND
 875525 root      20   0   12480      0      0 R   0.3   0.0   0:00.08 top
      1 root      20   0  172800      0      0 S   0.0   0.0   0:04.52 systemd

The main reason is that the batch size of the percpu counter is quite
large on these machines, caching a significant percpu value, since
converting mm's rss stats into percpu_counter by commit f1a7941243 ("mm:
convert mm's rss stats into percpu_counter").  Intuitively, the batch
number should be optimized, but on some paths, performance may take
precedence over statistical accuracy.  Therefore, introducing a new
interface to add the percpu statistical count and display it to users,
which can remove the confusion.  In addition, this change is not expected
to be on a performance-critical path, so the modification should be
acceptable.

In addition, the 'mm->rss_stat' is updated by using add_mm_counter() and
dec/inc_mm_counter(), which are all wrappers around
percpu_counter_add_batch().  In percpu_counter_add_batch(), there is
percpu batch caching to avoid 'fbc->lock' contention.  This patch changes
task_mem() and task_statm() to get the accurate mm counters under the
'fbc->lock', but this should not exacerbate kernel 'mm->rss_stat' lock
contention due to the percpu batch caching of the mm counters.  The
following test also confirm the theoretical analysis.

I run the stress-ng that stresses anon page faults in 32 threads on my 32
cores machine, while simultaneously running a script that starts 32
threads to busy-loop pread each stress-ng thread's /proc/pid/status
interface.  From the following data, I did not observe any obvious impact
of this patch on the stress-ng tests.

w/o patch:
stress-ng: info:  [6848]          4,399,219,085,152 CPU Cycles          67.327 B/sec
stress-ng: info:  [6848]          1,616,524,844,832 Instructions          24.740 B/sec (0.367 instr. per cycle)
stress-ng: info:  [6848]          39,529,792 Page Faults Total           0.605 M/sec
stress-ng: info:  [6848]          39,529,792 Page Faults Minor           0.605 M/sec

w/patch:
stress-ng: info:  [2485]          4,462,440,381,856 CPU Cycles          68.382 B/sec
stress-ng: info:  [2485]          1,615,101,503,296 Instructions          24.750 B/sec (0.362 instr. per cycle)
stress-ng: info:  [2485]          39,439,232 Page Faults Total           0.604 M/sec
stress-ng: info:  [2485]          39,439,232 Page Faults Minor           0.604 M/sec

On comparing a very simple app which just allocates & touches some
memory against v6.1 (which doesn't have f1a7941243) and latest Linus
tree (4c06e63b92) I can see that on latest Linus tree the values for
VmRSS, RssAnon and RssFile from /proc/self/status are all zeroes while
they do report values on v6.1 and a Linus tree with this patch.

Link: https://lkml.kernel.org/r/f4586b17f66f97c174f7fd1f8647374fdb53de1c.1749119050.git.baolin.wang@linux.alibaba.com
Fixes: f1a7941243 ("mm: convert mm's rss stats into percpu_counter")
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Aboorva Devarajan <aboorvad@linux.ibm.com>
Tested-by: Aboorva Devarajan <aboorvad@linux.ibm.com>
Tested-by Donet Tom <donettom@linux.ibm.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: SeongJae Park <sj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: David Hildenbrand <david@redhat.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-17 18:37:13 +02:00
Thomas Zimmermann
065bd940ee drm/framebuffer: Acquire internal references on GEM handles
commit f6bfc9afc7 upstream.

Acquire GEM handles in drm_framebuffer_init() and release them in
the corresponding drm_framebuffer_cleanup(). Ties the handle's
lifetime to the framebuffer. Not all GEM buffer objects have GEM
handles. If not set, no refcounting takes place. This is the case
for some fbdev emulation. This is not a problem as these GEM objects
do not use dma-bufs and drivers will not release them while fbdev
emulation is running. Framebuffer flags keep a bit per color plane
of which the framebuffer holds a GEM handle reference.

As all drivers use drm_framebuffer_init(), they will now all hold
dma-buf references as fixed in commit 5307dce878 ("drm/gem: Acquire
references on GEM handles for framebuffers").

In the GEM framebuffer helpers, restore the original ref counting
on buffer objects. As the helpers for handle refcounting are now
no longer called from outside the DRM core, unexport the symbols.

v3:
- don't mix internal flags with mode flags (Christian)
v2:
- track framebuffer handle refs by flag
- drop gma500 cleanup (Christian)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 5307dce878 ("drm/gem: Acquire references on GEM handles for framebuffers")
Reported-by: Bert Karwatzki <spasswolf@web.de>
Closes: https://lore.kernel.org/dri-devel/20250703115915.3096-1-spasswolf@web.de/
Tested-by: Bert Karwatzki <spasswolf@web.de>
Tested-by: Mario Limonciello <superm1@kernel.org>
Tested-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Anusha Srivatsa <asrivats@redhat.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Cc: <stable@vger.kernel.org>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20250707131224.249496-1-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-17 18:37:12 +02:00
Simona Vetter
2d2f07a994 drm/gem: Fix race in drm_gem_handle_create_tail()
commit bd46cece51 upstream.

Object creation is a careful dance where we must guarantee that the
object is fully constructed before it is visible to other threads, and
GEM buffer objects are no difference.

Final publishing happens by calling drm_gem_handle_create(). After
that the only allowed thing to do is call drm_gem_object_put() because
a concurrent call to the GEM_CLOSE ioctl with a correctly guessed id
(which is trivial since we have a linear allocator) can already tear
down the object again.

Luckily most drivers get this right, the very few exceptions I've
pinged the relevant maintainers for. Unfortunately we also need
drm_gem_handle_create() when creating additional handles for an
already existing object (e.g. GETFB ioctl or the various bo import
ioctl), and hence we cannot have a drm_gem_handle_create_and_put() as
the only exported function to stop these issues from happening.

Now unfortunately the implementation of drm_gem_handle_create() isn't
living up to standards: It does correctly finishe object
initialization at the global level, and hence is safe against a
concurrent tear down. But it also sets up the file-private aspects of
the handle, and that part goes wrong: We fully register the object in
the drm_file.object_idr before calling drm_vma_node_allow() or
obj->funcs->open, which opens up races against concurrent removal of
that handle in drm_gem_handle_delete().

Fix this with the usual two-stage approach of first reserving the
handle id, and then only registering the object after we've completed
the file-private setup.

Jacek reported this with a testcase of concurrently calling GEM_CLOSE
on a freshly-created object (which also destroys the object), but it
should be possible to hit this with just additional handles created
through import or GETFB without completed destroying the underlying
object with the concurrent GEM_CLOSE ioctl calls.

Note that the close-side of this race was fixed in f6cd7daecf ("drm:
Release driver references to handle before making it available
again"), which means a cool 9 years have passed until someone noticed
that we need to make this symmetry or there's still gaps left :-/
Without the 2-stage close approach we'd still have a race, therefore
that's an integral part of this bugfix.

More importantly, this means we can have NULL pointers behind
allocated id in our drm_file.object_idr. We need to check for that
now:

- drm_gem_handle_delete() checks for ERR_OR_NULL already

- drm_gem.c:object_lookup() also chekcs for NULL

- drm_gem_release() should never be called if there's another thread
  still existing that could call into an IOCTL that creates a new
  handle, so cannot race. For paranoia I added a NULL check to
  drm_gem_object_release_handle() though.

- most drivers (etnaviv, i915, msm) are find because they use
  idr_find(), which maps both ENOENT and NULL to NULL.

- drivers using idr_for_each_entry() should also be fine, because
  idr_get_next does filter out NULL entries and continues the
  iteration.

- The same holds for drm_show_memory_stats().

v2: Use drm_WARN_ON (Thomas)

Reported-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Tested-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: stable@vger.kernel.org
Cc: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@gmail.com>
Cc: Simona Vetter <simona@ffwll.ch>
Signed-off-by: Simona Vetter <simona.vetter@intel.com>
Signed-off-by: Simona Vetter <simona.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20250707151814.603897-1-simona.vetter@ffwll.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-17 18:37:11 +02:00
Matthew Brost
e2d6547dc8 drm/sched: Increment job count before swapping tail spsc queue
commit 8af39ec5cf upstream.

A small race exists between spsc_queue_push and the run-job worker, in
which spsc_queue_push may return not-first while the run-job worker has
already idled due to the job count being zero. If this race occurs, job
scheduling stops, leading to hangs while waiting on the job’s DMA
fences.

Seal this race by incrementing the job count before appending to the
SPSC queue.

This race was observed on a drm-tip 6.16-rc1 build with the Xe driver in
an SVM test case.

Fixes: 1b1f42d8fd ("drm: move amd_gpu_scheduler into common location")
Fixes: 27105db6c6 ("drm/amdgpu: Add SPSC queue to scheduler.")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Link: https://lore.kernel.org/r/20250613212013.719312-1-matthew.brost@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-17 18:37:11 +02:00
Nikunj A Dadhania
5cb498b20b KVM: SVM: Add missing member in SNP_LAUNCH_START command structure
commit 51a4273dca upstream.

The sev_data_snp_launch_start structure should include a 4-byte
desired_tsc_khz field before the gosvw field, which was missed in the
initial implementation. As a result, the structure is 4 bytes shorter than
expected by the firmware, causing the gosvw field to start 4 bytes early.
Fix this by adding the missing 4-byte member for the desired TSC frequency.

Fixes: 3a45dc2b41 ("crypto: ccp: Define the SEV-SNP commands")
Cc: stable@vger.kernel.org
Suggested-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Tested-by: Vaishali Thakkar <vaishali.thakkar@suse.com>
Signed-off-by: Nikunj A Dadhania <nikunj@amd.com>
Link: https://lore.kernel.org/r/20250408093213.57962-3-nikunj@amd.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-17 18:37:08 +02:00
Stefano Garzarella
8fb2802a16 vsock: fix vsock_proto declaration
[ Upstream commit 1e3b66e326 ]

From commit 634f1a7110 ("vsock: support sockmap"), `struct proto
vsock_proto`, defined in af_vsock.c, is not static anymore, since it's
used by vsock_bpf.c.

If CONFIG_BPF_SYSCALL is not defined, `make C=2` will print a warning:
    $ make O=build C=2 W=1 net/vmw_vsock/
      ...
      CC [M]  net/vmw_vsock/af_vsock.o
      CHECK   ../net/vmw_vsock/af_vsock.c
    ../net/vmw_vsock/af_vsock.c:123:14: warning: symbol 'vsock_proto' was not declared. Should it be static?

Declare `vsock_proto` regardless of CONFIG_BPF_SYSCALL, since it's defined
in af_vsock.c, which is built regardless of CONFIG_BPF_SYSCALL.

Fixes: 634f1a7110 ("vsock: support sockmap")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://patch.msgid.link/20250703112329.28365-1-sgarzare@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-17 18:37:05 +02:00
Bard Liao
3653643584 ASoC: soc-acpi: add get_function_tplg_files ops
[ Upstream commit d1e70eed0b ]

We always use a single topology that contains all PCM devices belonging
to a machine configuration.
However, with SDCA, we want to be able to load function topologies based
on the supported device functions. This change is in preparation for
loading those function topologies.

Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Liam Girdwood <liam.r.girdwood@intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://patch.msgid.link/20250414063239.85200-4-yung-chuan.liao@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Stable-dep-of: a7528e9bea ("ASoC: Intel: soc-acpi: arl: Correct order of cs42l43 matches")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-17 18:37:02 +02:00
Borislav Petkov (AMD)
7a0395f660 x86/bugs: Add a Transient Scheduler Attacks mitigation
Commit d8010d4ba4 upstream.

Add the required features detection glue to bugs.c et all in order to
support the TSA mitigation.

Co-developed-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-10 16:05:14 +02:00
Heikki Krogerus
7cb8750160 usb: acpi: fix device link removal
commit 3b18405763 upstream.

The device link to the USB4 host interface has to be removed
manually since it's no longer auto removed.

Fixes: 623dae3e70 ("usb: acpi: fix boot hang due to early incorrect 'tunneled' USB3 device links")
Cc: stable <stable@kernel.org>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Link: https://lore.kernel.org/r/20250611111415.2707865-1-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-10 16:05:11 +02:00
Shivank Garg
f94c422157 fs: export anon_inode_make_secure_inode() and fix secretmem LSM bypass
[ Upstream commit cbe4134ea4 ]

Export anon_inode_make_secure_inode() to allow KVM guest_memfd to create
anonymous inodes with proper security context. This replaces the current
pattern of calling alloc_anon_inode() followed by
inode_init_security_anon() for creating security context manually.

This change also fixes a security regression in secretmem where the
S_PRIVATE flag was not cleared after alloc_anon_inode(), causing
LSM/SELinux checks to be bypassed for secretmem file descriptors.

As guest_memfd currently resides in the KVM module, we need to export this
symbol for use outside the core kernel. In the future, guest_memfd might be
moved to core-mm, at which point the symbols no longer would have to be
exported. When/if that happens is still unclear.

Fixes: 2bfe15c526 ("mm: create security context for memfd_secret inodes")
Suggested-by: David Hildenbrand <david@redhat.com>
Suggested-by: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://lore.kernel.org/20250620070328.803704-3-shivankg@amd.com
Acked-by: "Mike Rapoport (Microsoft)" <rppt@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10 16:05:09 +02:00
Peter Zijlstra
cdd9862252 module: Provide EXPORT_SYMBOL_GPL_FOR_MODULES() helper
[ Upstream commit 707f853d7f ]

Helper macro to more easily limit the export of a symbol to a given
list of modules.

Eg:

  EXPORT_SYMBOL_GPL_FOR_MODULES(preempt_notifier_inc, "kvm");

will limit the use of said function to kvm.ko, any other module trying
to use this symbol will refure to load (and get modpost build
failures).

Requested-by: Masahiro Yamada <masahiroy@kernel.org>
Requested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Stable-dep-of: cbe4134ea4 ("fs: export anon_inode_make_secure_inode() and fix secretmem LSM bypass")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10 16:05:08 +02:00
Al Viro
e036efbe58 add a string-to-qstr constructor
[ Upstream commit c1feab95e0 ]

Quite a few places want to build a struct qstr by given string;
it would be convenient to have a primitive doing that, rather
than open-coding it via QSTR_INIT().

The closest approximation was in bcachefs, but that expands to
initializer list - {.len = strlen(string), .name = string}.
It would be more useful to have it as compound literal -
(struct qstr){.len = strlen(string), .name = string}.

Unlike initializer list it's a valid expression.  What's more,
it's a valid lvalue - it's an equivalent of anonymous local
variable with such initializer, so the things like
	path->dentry = d_alloc_pseudo(mnt->mnt_sb, &QSTR(name));
are valid.  It can also be used as initializer, with identical
effect -
	struct qstr x = (struct qstr){.name = s, .len = strlen(s)};
is equivalent to
	struct qstr anon_variable = {.name = s, .len = strlen(s)};
	struct qstr x = anon_variable;
	// anon_variable is never used after that point
and any even remotely sane compiler will manage to collapse that
into
	struct qstr x = {.name = s, .len = strlen(s)};

What compound literals can't be used for is initialization of
global variables, but those are covered by QSTR_INIT().

This commit lifts definition(s) of QSTR() into linux/dcache.h,
converts it to compound literal (all bcachefs users are fine
with that) and converts assorted open-coded instances to using
that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Stable-dep-of: cbe4134ea4 ("fs: export anon_inode_make_secure_inode() and fix secretmem LSM bypass")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10 16:05:08 +02:00
Tasos Sahanidis
3ce57d493d ata: libata-acpi: Do not assume 40 wire cable if no devices are enabled
[ Upstream commit 33877220b8 ]

On at least an ASRock 990FX Extreme 4 with a VIA VT6330, the devices
have not yet been enabled by the first time ata_acpi_cbl_80wire() is
called. This means that the ata_for_each_dev loop is never entered,
and a 40 wire cable is assumed.

The VIA controller on this board does not report the cable in the PCI
config space, thus having to fall back to ACPI even though no SATA
bridge is present.

The _GTM values are correctly reported by the firmware through ACPI,
which has already set up faster transfer modes, but due to the above
the controller is forced down to a maximum of UDMA/33.

Resolve this by modifying ata_acpi_cbl_80wire() to directly return the
cable type. First, an unknown cable is assumed which preserves the mode
set by the firmware, and then on subsequent calls when the devices have
been enabled, an 80 wire cable is correctly detected.

Since the function now directly returns the cable type, it is renamed
to ata_acpi_cbl_pata_type().

Signed-off-by: Tasos Sahanidis <tasos@tasossah.com>
Link: https://lore.kernel.org/r/20250519085945.1399466-1-tasos@tasossah.com
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10 16:05:06 +02:00
Yonghong Song
4265682c29 bpf: Do not include stack ptr register in precision backtracking bookkeeping
[ Upstream commit e2d2115e56 ]

Yi Lai reported an issue ([1]) where the following warning appears
in kernel dmesg:
  [   60.643604] verifier backtracking bug
  [   60.643635] WARNING: CPU: 10 PID: 2315 at kernel/bpf/verifier.c:4302 __mark_chain_precision+0x3a6c/0x3e10
  [   60.648428] Modules linked in: bpf_testmod(OE)
  [   60.650471] CPU: 10 UID: 0 PID: 2315 Comm: test_progs Tainted: G           OE       6.15.0-rc4-gef11287f8289-dirty #327 PREEMPT(full)
  [   60.654385] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
  [   60.656682] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
  [   60.660475] RIP: 0010:__mark_chain_precision+0x3a6c/0x3e10
  [   60.662814] Code: 5a 30 84 89 ea e8 c4 d9 01 00 80 3d 3e 7d d8 04 00 0f 85 60 fa ff ff c6 05 31 7d d8 04
                       01 48 c7 c7 00 58 30 84 e8 c4 06 a5 ff <0f> 0b e9 46 fa ff ff 48 ...
  [   60.668720] RSP: 0018:ffff888116cc7298 EFLAGS: 00010246
  [   60.671075] RAX: 54d70e82dfd31900 RBX: ffff888115b65e20 RCX: 0000000000000000
  [   60.673659] RDX: 0000000000000001 RSI: 0000000000000004 RDI: 00000000ffffffff
  [   60.676241] RBP: 0000000000000400 R08: ffff8881f6f23bd3 R09: 1ffff1103ede477a
  [   60.678787] R10: dffffc0000000000 R11: ffffed103ede477b R12: ffff888115b60ae8
  [   60.681420] R13: 1ffff11022b6cbc4 R14: 00000000fffffff2 R15: 0000000000000001
  [   60.684030] FS:  00007fc2aedd80c0(0000) GS:ffff88826fa8a000(0000) knlGS:0000000000000000
  [   60.686837] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [   60.689027] CR2: 000056325369e000 CR3: 000000011088b002 CR4: 0000000000370ef0
  [   60.691623] Call Trace:
  [   60.692821]  <TASK>
  [   60.693960]  ? __pfx_verbose+0x10/0x10
  [   60.695656]  ? __pfx_disasm_kfunc_name+0x10/0x10
  [   60.697495]  check_cond_jmp_op+0x16f7/0x39b0
  [   60.699237]  do_check+0x58fa/0xab10
  ...

Further analysis shows the warning is at line 4302 as below:

  4294                 /* static subprog call instruction, which
  4295                  * means that we are exiting current subprog,
  4296                  * so only r1-r5 could be still requested as
  4297                  * precise, r0 and r6-r10 or any stack slot in
  4298                  * the current frame should be zero by now
  4299                  */
  4300                 if (bt_reg_mask(bt) & ~BPF_REGMASK_ARGS) {
  4301                         verbose(env, "BUG regs %x\n", bt_reg_mask(bt));
  4302                         WARN_ONCE(1, "verifier backtracking bug");
  4303                         return -EFAULT;
  4304                 }

With the below test (also in the next patch):
  __used __naked static void __bpf_jmp_r10(void)
  {
	asm volatile (
	"r2 = 2314885393468386424 ll;"
	"goto +0;"
	"if r2 <= r10 goto +3;"
	"if r1 >= -1835016 goto +0;"
	"if r2 <= 8 goto +0;"
	"if r3 <= 0 goto +0;"
	"exit;"
	::: __clobber_all);
  }

  SEC("?raw_tp")
  __naked void bpf_jmp_r10(void)
  {
	asm volatile (
	"r3 = 0 ll;"
	"call __bpf_jmp_r10;"
	"r0 = 0;"
	"exit;"
	::: __clobber_all);
  }

The following is the verifier failure log:
  0: (18) r3 = 0x0                      ; R3_w=0
  2: (85) call pc+2
  caller:
   R10=fp0
  callee:
   frame1: R1=ctx() R3_w=0 R10=fp0
  5: frame1: R1=ctx() R3_w=0 R10=fp0
  ; asm volatile ("                                 \ @ verifier_precision.c:184
  5: (18) r2 = 0x20202000256c6c78       ; frame1: R2_w=0x20202000256c6c78
  7: (05) goto pc+0
  8: (bd) if r2 <= r10 goto pc+3        ; frame1: R2_w=0x20202000256c6c78 R10=fp0
  9: (35) if r1 >= 0xffe3fff8 goto pc+0         ; frame1: R1=ctx()
  10: (b5) if r2 <= 0x8 goto pc+0
  mark_precise: frame1: last_idx 10 first_idx 0 subseq_idx -1
  mark_precise: frame1: regs=r2 stack= before 9: (35) if r1 >= 0xffe3fff8 goto pc+0
  mark_precise: frame1: regs=r2 stack= before 8: (bd) if r2 <= r10 goto pc+3
  mark_precise: frame1: regs=r2,r10 stack= before 7: (05) goto pc+0
  mark_precise: frame1: regs=r2,r10 stack= before 5: (18) r2 = 0x20202000256c6c78
  mark_precise: frame1: regs=r10 stack= before 2: (85) call pc+2
  BUG regs 400

The main failure reason is due to r10 in precision backtracking bookkeeping.
Actually r10 is always precise and there is no need to add it for the precision
backtracking bookkeeping.

One way to fix the issue is to prevent bt_set_reg() if any src/dst reg is
r10. Andrii suggested to go with push_insn_history() approach to avoid
explicitly checking r10 in backtrack_insn().

This patch added push_insn_history() support for cond_jmp like 'rX <op> rY'
operations. In check_cond_jmp_op(), if any of rX or rY is a stack pointer,
push_insn_history() will record such information, and later backtrack_insn()
will do bt_set_reg() properly for those register(s).

  [1] https://lore.kernel.org/bpf/Z%2F8q3xzpU59CIYQE@ly-workstation/

Reported by: Yi Lai <yi1.lai@linux.intel.com>

Fixes: 407958a0e9 ("bpf: encapsulate precision backtracking bookkeeping")
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250524041335.4046126-1-yonghong.song@linux.dev
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10 16:05:00 +02:00
Andrii Nakryiko
c5474a7b04 bpf: use common instruction history across all states
[ Upstream commit 96a30e469c ]

Instead of allocating and copying instruction history each time we
enqueue child verifier state, switch to a model where we use one common
dynamically sized array of instruction history entries across all states.

The key observation for proving this is correct is that instruction
history is only relevant while state is active, which means it either is
a current state (and thus we are actively modifying instruction history
and no other state can interfere with us) or we are checkpointed state
with some children still active (either enqueued or being current).

In the latter case our portion of instruction history is finalized and
won't change or grow, so as long as we keep it immutable until the state
is finalized, we are good.

Now, when state is finalized and is put into state hash for potentially
future pruning lookups, instruction history is not used anymore. This is
because instruction history is only used by precision marking logic, and
we never modify precision markings for finalized states.

So, instead of each state having its own small instruction history, we
keep a global dynamically-sized instruction history, where each state in
current DFS path from root to active state remembers its portion of
instruction history. Current state can append to this history, but
cannot modify any of its parent histories.

Async callback state enqueueing, while logically detached from parent
state, still is part of verification backtracking tree, so has to follow
the same schema as normal state checkpoints.

Because the insn_hist array can be grown through realloc, states don't
keep pointers, they instead maintain two indices, [start, end), into
global instruction history array. End is exclusive index, so
`start == end` means there is no relevant instruction history.

This eliminates a lot of allocations and minimizes overall memory usage.

For instance, running a worst-case test from [0] (but without the
heuristics-based fix [1]), it took 12.5 minutes until we get -ENOMEM.
With the changes in this patch the whole test succeeds in 10 minutes
(very slow, so heuristics from [1] is important, of course).

To further validate correctness, veristat-based comparison was performed for
Meta production BPF objects and BPF selftests objects. In both cases there
were no differences *at all* in terms of verdict or instruction and state
counts, providing a good confidence in the change.

Having this low-memory-overhead solution of keeping dynamic
per-instruction history cheaply opens up some new possibilities, like
keeping extra information for literally every single validated
instruction. This will be used for simplifying precision backpropagation
logic in follow up patches.

  [0] https://lore.kernel.org/bpf/20241029172641.1042523-2-eddyz87@gmail.com/
  [1] https://lore.kernel.org/bpf/20241029172641.1042523-1-eddyz87@gmail.com/

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20241115001303.277272-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Stable-dep-of: e2d2115e56 ("bpf: Do not include stack ptr register in precision backtracking bookkeeping")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10 16:05:00 +02:00
Christian Marangi
d78f79a2c1 spinlock: extend guard with spinlock_bh variants
[ Upstream commit d610473317 ]

Extend guard APIs with missing raw/spinlock_bh variants.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Stable-dep-of: c7e6804362 ("crypto: zynqmp-sha - Add locking")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10 16:04:54 +02:00
RD Babiera
5581e694d3 usb: typec: altmodes/displayport: do not index invalid pin_assignments
commit af4db5a35a upstream.

A poorly implemented DisplayPort Alt Mode port partner can indicate
that its pin assignment capabilities are greater than the maximum
value, DP_PIN_ASSIGN_F. In this case, calls to pin_assignment_show
will cause a BRK exception due to an out of bounds array access.

Prevent for loop in pin_assignment_show from accessing
invalid values in pin_assignments by adding DP_PIN_ASSIGN_MAX
value in typec_dp.h and using i < DP_PIN_ASSIGN_MAX as a loop
condition.

Fixes: 0e3bb7d689 ("usb: typec: Add driver for DisplayPort alternate mode")
Cc: stable <stable@kernel.org>
Signed-off-by: RD Babiera <rdbabiera@google.com>
Reviewed-by: Badhri Jagan Sridharan <badhri@google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20250618224943.3263103-2-rdbabiera@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-10 16:04:43 +02:00
Stefano Garzarella
dbcd546400 vsock/uapi: fix linux/vm_sockets.h userspace compilation errors
[ Upstream commit 22bbc1dcd0 ]

If a userspace application just include <linux/vm_sockets.h> will fail
to build with the following errors:

    /usr/include/linux/vm_sockets.h:182:39: error: invalid application of ‘sizeof’ to incomplete type ‘struct sockaddr’
      182 |         unsigned char svm_zero[sizeof(struct sockaddr) -
          |                                       ^~~~~~
    /usr/include/linux/vm_sockets.h:183:39: error: ‘sa_family_t’ undeclared here (not in a function)
      183 |                                sizeof(sa_family_t) -
          |

Include <sys/socket.h> for userspace (guarded by ifndef __KERNEL__)
where `struct sockaddr` and `sa_family_t` are defined.
We already do something similar in <linux/mptcp.h> and <linux/if.h>.

Fixes: d021c34405 ("VSOCK: Introduce VM Sockets")
Reported-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://patch.msgid.link/20250623100053.40979-1-sgarzare@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-06 11:01:40 +02:00
Kuniyuki Iwashima
ce23b73f0f Bluetooth: hci_core: Fix use-after-free in vhci_flush()
[ Upstream commit 1d6123102e ]

syzbot reported use-after-free in vhci_flush() without repro. [0]

From the splat, a thread close()d a vhci file descriptor while
its device was being used by iotcl() on another thread.

Once the last fd refcnt is released, vhci_release() calls
hci_unregister_dev(), hci_free_dev(), and kfree() for struct
vhci_data, which is set to hci_dev->dev->driver_data.

The problem is that there is no synchronisation after unlinking
hdev from hci_dev_list in hci_unregister_dev().  There might be
another thread still accessing the hdev which was fetched before
the unlink operation.

We can use SRCU for such synchronisation.

Let's run hci_dev_reset() under SRCU and wait for its completion
in hci_unregister_dev().

Another option would be to restore hci_dev->destruct(), which was
removed in commit 587ae086f6 ("Bluetooth: Remove unused
hci-destruct cb").  However, this would not be a good solution, as
we should not run hci_unregister_dev() while there are in-flight
ioctl() requests, which could lead to another data-race KCSAN splat.

Note that other drivers seem to have the same problem, for exmaple,
virtbt_remove().

[0]:
BUG: KASAN: slab-use-after-free in skb_queue_empty_lockless include/linux/skbuff.h:1891 [inline]
BUG: KASAN: slab-use-after-free in skb_queue_purge_reason+0x99/0x360 net/core/skbuff.c:3937
Read of size 8 at addr ffff88807cb8d858 by task syz.1.219/6718

CPU: 1 UID: 0 PID: 6718 Comm: syz.1.219 Not tainted 6.16.0-rc1-syzkaller-00196-g08207f42d3ff #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xd2/0x2b0 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 skb_queue_empty_lockless include/linux/skbuff.h:1891 [inline]
 skb_queue_purge_reason+0x99/0x360 net/core/skbuff.c:3937
 skb_queue_purge include/linux/skbuff.h:3368 [inline]
 vhci_flush+0x44/0x50 drivers/bluetooth/hci_vhci.c:69
 hci_dev_do_reset net/bluetooth/hci_core.c:552 [inline]
 hci_dev_reset+0x420/0x5c0 net/bluetooth/hci_core.c:592
 sock_do_ioctl+0xd9/0x300 net/socket.c:1190
 sock_ioctl+0x576/0x790 net/socket.c:1311
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcf5b98e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcf5c7b9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fcf5bbb6160 RCX: 00007fcf5b98e929
RDX: 0000000000000000 RSI: 00000000400448cb RDI: 0000000000000009
RBP: 00007fcf5ba10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fcf5bbb6160 R15: 00007ffd6353d528
 </TASK>

Allocated by task 6535:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 vhci_open+0x57/0x360 drivers/bluetooth/hci_vhci.c:635
 misc_open+0x2bc/0x330 drivers/char/misc.c:161
 chrdev_open+0x4c9/0x5e0 fs/char_dev.c:414
 do_dentry_open+0xdf0/0x1970 fs/open.c:964
 vfs_open+0x3b/0x340 fs/open.c:1094
 do_open fs/namei.c:3887 [inline]
 path_openat+0x2ee5/0x3830 fs/namei.c:4046
 do_filp_open+0x1fa/0x410 fs/namei.c:4073
 do_sys_openat2+0x121/0x1c0 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1463
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 6535:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kfree+0x18e/0x440 mm/slub.c:4842
 vhci_release+0xbc/0xd0 drivers/bluetooth/hci_vhci.c:671
 __fput+0x44c/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x6ad/0x22e0 kernel/exit.c:955
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1104
 __do_sys_exit_group kernel/exit.c:1115 [inline]
 __se_sys_exit_group kernel/exit.c:1113 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1113
 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807cb8d800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 88 bytes inside of
 freed 1024-byte region [ffff88807cb8d800, ffff88807cb8dc00)

Fixes: bf18c7118c ("Bluetooth: vhci: Free driver_data on file release")
Reported-by: syzbot+2faa4825e556199361f9@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=f62d64848fc4c7c30cd6
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Acked-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-06 11:01:39 +02:00
Andrzej Kacprowski
0c3fa6e844 accel/ivpu: Remove copy engine support
[ Upstream commit 94b2a2c0e7 ]

Copy engine was deprecated by the FW and is no longer supported.
Compute engine includes all copy engine functionality and should be used
instead.

This change does not affect user space as the copy engine was never
used outside of a couple of tests.

Signed-off-by: Andrzej Kacprowski <Andrzej.Kacprowski@intel.com>
Reviewed-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241017145817.121590-4-jacek.lawrynowicz@linux.intel.com
Stable-dep-of: a47e36dc5d ("accel/ivpu: Trigger device recovery on engine reset/resume failure")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-06 11:01:37 +02:00
Willem de Bruijn
3c44ebad5a ipv6: replace ipcm6_init calls with ipcm6_init_sk
commit 096208592b upstream.

This initializes tclass and dontfrag before cmsg parsing, removing the
need for explicit checks against -1 in each caller.

Leave hlimit set to -1, because its full initialization
(in ip6_sk_dst_hoplimit) requires more state (dst, flowi6, ..).

This also prepares for calling sockcm_init in a follow-on patch.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250214222720.3205500-7-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-27 11:11:41 +01:00
Gao Xiang
50189d9c5e erofs: remove unused trace event erofs_destroy_inode
commit 30b5844480 upstream.

The trace event `erofs_destroy_inode` was added but remains unused. This
unused event contributes approximately 5KB to the kernel module size.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Closes: https://lore.kernel.org/r/20250612224906.15000244@batman.local.home
Fixes: 13f06f48f7 ("staging: erofs: support tracepoint")
Cc: stable@vger.kernel.org
Reviewed-by: Hongbo Li <lihongbo22@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20250617054056.3232365-1-hsiangkao@linux.alibaba.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-27 11:11:40 +01:00
Paul Chaignon
2516299184 bpf: Fix L4 csum update on IPv6 in CHECKSUM_COMPLETE
commit ead7f9b8de upstream.

In Cilium, we use bpf_csum_diff + bpf_l4_csum_replace to, among other
things, update the L4 checksum after reverse SNATing IPv6 packets. That
use case is however not currently supported and leads to invalid
skb->csum values in some cases. This patch adds support for IPv6 address
changes in bpf_l4_csum_update via a new flag.

When calling bpf_l4_csum_replace in Cilium, it ends up calling
inet_proto_csum_replace_by_diff:

    1:  void inet_proto_csum_replace_by_diff(__sum16 *sum, struct sk_buff *skb,
    2:                                       __wsum diff, bool pseudohdr)
    3:  {
    4:      if (skb->ip_summed != CHECKSUM_PARTIAL) {
    5:          csum_replace_by_diff(sum, diff);
    6:          if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
    7:              skb->csum = ~csum_sub(diff, skb->csum);
    8:      } else if (pseudohdr) {
    9:          *sum = ~csum_fold(csum_add(diff, csum_unfold(*sum)));
    10:     }
    11: }

The bug happens when we're in the CHECKSUM_COMPLETE state. We've just
updated one of the IPv6 addresses. The helper now updates the L4 header
checksum on line 5. Next, it updates skb->csum on line 7. It shouldn't.

For an IPv6 packet, the updates of the IPv6 address and of the L4
checksum will cancel each other. The checksums are set such that
computing a checksum over the packet including its checksum will result
in a sum of 0. So the same is true here when we update the L4 checksum
on line 5. We'll update it as to cancel the previous IPv6 address
update. Hence skb->csum should remain untouched in this case.

The same bug doesn't affect IPv4 packets because, in that case, three
fields are updated: the IPv4 address, the IP checksum, and the L4
checksum. The change to the IPv4 address and one of the checksums still
cancel each other in skb->csum, but we're left with one checksum update
and should therefore update skb->csum accordingly. That's exactly what
inet_proto_csum_replace_by_diff does.

This special case for IPv6 L4 checksums is also described atop
inet_proto_csum_replace16, the function we should be using in this case.

This patch introduces a new bpf_l4_csum_replace flag, BPF_F_IPV6,
to indicate that we're updating the L4 checksum of an IPv6 packet. When
the flag is set, inet_proto_csum_replace_by_diff will skip the
skb->csum update.

Fixes: 7d672345ed ("bpf: add generic bpf_csum_diff helper")
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/96a6bc3a443e6f0b21ff7b7834000e17fb549e05.1748509484.git.paul.chaignon@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-27 11:11:40 +01:00
Paul Chaignon
dc5f0aef9e net: Fix checksum update for ILA adj-transport
commit 6043b794c7 upstream.

During ILA address translations, the L4 checksums can be handled in
different ways. One of them, adj-transport, consist in parsing the
transport layer and updating any found checksum. This logic relies on
inet_proto_csum_replace_by_diff and produces an incorrect skb->csum when
in state CHECKSUM_COMPLETE.

This bug can be reproduced with a simple ILA to SIR mapping, assuming
packets are received with CHECKSUM_COMPLETE:

  $ ip a show dev eth0
  14: eth0@if15: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
      link/ether 62:ae:35:9e:0f:8d brd ff:ff:ff:ff:ff:ff link-netnsid 0
      inet6 3333:0:0:1::c078/64 scope global
         valid_lft forever preferred_lft forever
      inet6 fd00:10:244:1::c078/128 scope global nodad
         valid_lft forever preferred_lft forever
      inet6 fe80::60ae:35ff:fe9e:f8d/64 scope link proto kernel_ll
         valid_lft forever preferred_lft forever
  $ ip ila add loc_match fd00:10:244:1 loc 3333:0:0:1 \
      csum-mode adj-transport ident-type luid dev eth0

Then I hit [fd00:10:244:1::c078]:8000 with a server listening only on
[3333:0:0:1::c078]:8000. With the bug, the SYN packet is dropped with
SKB_DROP_REASON_TCP_CSUM after inet_proto_csum_replace_by_diff changed
skb->csum. The translation and drop are visible on pwru [1] traces:

  IFACE   TUPLE                                                        FUNC
  eth0:9  [fd00:10:244:3::3d8]:51420->[fd00:10:244:1::c078]:8000(tcp)  ipv6_rcv
  eth0:9  [fd00:10:244:3::3d8]:51420->[fd00:10:244:1::c078]:8000(tcp)  ip6_rcv_core
  eth0:9  [fd00:10:244:3::3d8]:51420->[fd00:10:244:1::c078]:8000(tcp)  nf_hook_slow
  eth0:9  [fd00:10:244:3::3d8]:51420->[fd00:10:244:1::c078]:8000(tcp)  inet_proto_csum_replace_by_diff
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     tcp_v6_early_demux
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     ip6_route_input
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     ip6_input
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     ip6_input_finish
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     ip6_protocol_deliver_rcu
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     raw6_local_deliver
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     ipv6_raw_deliver
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     tcp_v6_rcv
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     __skb_checksum_complete
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     kfree_skb_reason(SKB_DROP_REASON_TCP_CSUM)
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     skb_release_head_state
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     skb_release_data
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     skb_free_head
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     kfree_skbmem

This is happening because inet_proto_csum_replace_by_diff is updating
skb->csum when it shouldn't. The L4 checksum is updated such that it
"cancels" the IPv6 address change in terms of checksum computation, so
the impact on skb->csum is null.

Note this would be different for an IPv4 packet since three fields
would be updated: the IPv4 address, the IP checksum, and the L4
checksum. Two would cancel each other and skb->csum would still need
to be updated to take the L4 checksum change into account.

This patch fixes it by passing an ipv6 flag to
inet_proto_csum_replace_by_diff, to skip the skb->csum update if we're
in the IPv6 case. Note the behavior of the only other user of
inet_proto_csum_replace_by_diff, the BPF subsystem, is left as is in
this patch and fixed in the subsequent patch.

With the fix, using the reproduction from above, I can confirm
skb->csum is not touched by inet_proto_csum_replace_by_diff and the TCP
SYN proceeds to the application after the ILA translation.

Link: https://github.com/cilium/pwru [1]
Fixes: 65d7ab8de5 ("net: Identifier Locator Addressing module")
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/b5539869e3550d46068504feb02d37653d939c0b.1748509484.git.paul.chaignon@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-27 11:11:40 +01:00
Jann Horn
9cf5b2a3b7 mm/hugetlb: unshare page tables during VMA split, not before
commit 081056dc00 upstream.

Currently, __split_vma() triggers hugetlb page table unsharing through
vm_ops->may_split().  This happens before the VMA lock and rmap locks are
taken - which is too early, it allows racing VMA-locked page faults in our
process and racing rmap walks from other processes to cause page tables to
be shared again before we actually perform the split.

Fix it by explicitly calling into the hugetlb unshare logic from
__split_vma() in the same place where THP splitting also happens.  At that
point, both the VMA and the rmap(s) are write-locked.

An annoying detail is that we can now call into the helper
hugetlb_unshare_pmds() from two different locking contexts:

1. from hugetlb_split(), holding:
    - mmap lock (exclusively)
    - VMA lock
    - file rmap lock (exclusively)
2. hugetlb_unshare_all_pmds(), which I think is designed to be able to
   call us with only the mmap lock held (in shared mode), but currently
   only runs while holding mmap lock (exclusively) and VMA lock

Backporting note:
This commit fixes a racy protection that was introduced in commit
b30c14cd61 ("hugetlb: unshare some PMDs when splitting VMAs"); that
commit claimed to fix an issue introduced in 5.13, but it should actually
also go all the way back.

[jannh@google.com: v2]
  Link: https://lkml.kernel.org/r/20250528-hugetlb-fixes-splitrace-v2-1-1329349bad1a@google.com
Link: https://lkml.kernel.org/r/20250528-hugetlb-fixes-splitrace-v2-0-1329349bad1a@google.com
Link: https://lkml.kernel.org/r/20250527-hugetlb-fixes-splitrace-v1-1-f4136f5ec58a@google.com
Fixes: 39dde65c99 ("[PATCH] shared page table for hugetlb page")
Signed-off-by: Jann Horn <jannh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>	[b30c14cd61: hugetlb: unshare some PMDs when splitting VMAs]
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[stable backport: added missing include]
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-27 11:11:40 +01:00
Kuniyuki Iwashima
3d828519bd atm: Revert atm_account_tx() if copy_from_iter_full() fails.
commit 7851263998 upstream.

In vcc_sendmsg(), we account skb->truesize to sk->sk_wmem_alloc by
atm_account_tx().

It is expected to be reverted by atm_pop_raw() later called by
vcc->dev->ops->send(vcc, skb).

However, vcc_sendmsg() misses the same revert when copy_from_iter_full()
fails, and then we will leak a socket.

Let's factorise the revert part as atm_return_tx() and call it in
the failure path.

Note that the corresponding sk_wmem_alloc operation can be found in
alloc_tx() as of the blamed commit.

  $ git blame -L:alloc_tx net/atm/common.c c55fa3cccb~

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: Simon Horman <horms@kernel.org>
Closes: https://lore.kernel.org/netdev/20250614161959.GR414686@horms.kernel.org/
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250616182147.963333-3-kuni1840@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-27 11:11:39 +01:00
Toke Høiland-Jørgensen
2112fba7b7 Revert "mac80211: Dynamically set CoDel parameters per station"
[ Upstream commit 4876376988 ]

This reverts commit 484a54c2e5. The CoDel
parameter change essentially disables CoDel on slow stations, with some
questionable assumptions, as Dave pointed out in [0]. Quoting from
there:

  But here are my pithy comments as to why this part of mac80211 is so
  wrong...

   static void sta_update_codel_params(struct sta_info *sta, u32 thr)
   {
  -       if (thr && thr < STA_SLOW_THRESHOLD * sta->local->num_sta) {

  1) sta->local->num_sta is the number of associated, rather than
  active, stations. "Active" stations in the last 50ms or so, might have
  been a better thing to use, but as most people have far more than that
  associated, we end up with really lousy codel parameters, all the
  time. Mistake numero uno!

  2) The STA_SLOW_THRESHOLD was completely arbitrary in 2016.

  -               sta->cparams.target = MS2TIME(50);

  This, by itself, was probably not too bad. 30ms might have been
  better, at the time, when we were battling powersave etc, but 20ms was
  enough, really, to cover most scenarios, even where we had low rate
  2Ghz multicast to cope with. Even then, codel has a hard time finding
  any sane drop rate at all, with a target this high.

  -               sta->cparams.interval = MS2TIME(300);

  But this was horrible, a total mistake, that is leading to codel being
  completely ineffective in almost any scenario on clients or APS.
  100ms, even 80ms, here, would be vastly better than this insanity. I'm
  seeing 5+seconds of delay accumulated in a bunch of otherwise happily
  fq-ing APs....

  100ms of observed jitter during a flow is enough. Certainly (in 2016)
  there were interactions with powersave that I did not understand, and
  still don't, but if you are transmitting in the first place, powersave
  shouldn't be a problemmmm.....

  -               sta->cparams.ecn = false;

  At the time we were pretty nervous about ecn, I'm kind of sanguine
  about it now, and reliably indicating ecn seems better than turning it
  off for any reason.

  [...]

  In production, on p2p wireless, I've had 8ms and 80ms for target and
  interval for years now, and it works great.

I think Dave's arguments above are basically sound on the face of it,
and various experimentation with tighter CoDel parameters in the OpenWrt
community have show promising results[1]. So I don't think there's any
reason to keep this parameter fiddling; hence this revert.

[0] https://lore.kernel.org/linux-wireless/CAA93jw6NJ2cmLmMauz0xAgC2MGbBq6n0ZiZzAdkK0u4b+O2yXg@mail.gmail.com/
[1] https://forum.openwrt.org/t/reducing-multiplexing-latencies-still-further-in-wifi/133605/130

Suggested-By: Dave Taht <dave.taht@gmail.com>
In-memory-of: Dave Taht <dave.taht@gmail.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Link: https://patch.msgid.link/20250403183930.197716-1-toke@toke.dk
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-27 11:11:33 +01:00