linux.git/drivers/base, branch v6.6.45

devres: Fix memory leakage caused by driver API devm_free_percpu()

2024-08-03T06:54:25+00:00

commit bd50a974097bb82d52a458bd3ee39fb723129a0c upstream.

It will cause memory leakage when use driver API devm_free_percpu()
to free memory allocated by devm_alloc_percpu(), fixed by using
devres_release() instead of devres_destroy() within devm_free_percpu().

Fixes: ff86aae3b411 ("devres: add devm_alloc_percpu()")
Cc: stable@vger.kernel.org
Signed-off-by: Zijun Hu 
Link: https://lore.kernel.org/r/1719931914-19035-3-git-send-email-quic_zijuhu@quicinc.com
Signed-off-by: Greg Kroah-Hartman

devres: Fix devm_krealloc() wasting memory

2024-08-03T06:54:25+00:00

commit c884e3249f753dcef7a2b2023541ac1dc46b318e upstream.

Driver API devm_krealloc() calls alloc_dr() with wrong argument
@total_new_size, so causes more memory to be allocated than required
fix this memory waste by using @new_size as the argument for alloc_dr().

Fixes: f82485722e5d ("devres: provide devm_krealloc()")
Cc: stable@vger.kernel.org
Signed-off-by: Zijun Hu 
Link: https://lore.kernel.org/r/1719931914-19035-2-git-send-email-quic_zijuhu@quicinc.com
Signed-off-by: Greg Kroah-Hartman

regmap-i2c: Subtract reg size from max_write

2024-07-11T10:49:20+00:00

[ Upstream commit 611b7eb19d0a305d4de00280e4a71a1b15c507fc ]

Currently, when an adapter defines a max_write_len quirk,
the data will be chunked into data sizes equal to the
max_write_len quirk value.  But the payload will be increased by
the size of the register address before transmission.  The
resulting value always ends up larger than the limit set
by the quirk.

Avoid this error by setting regmap's max_write to the quirk's
max_write_len minus the number of bytes for the register and
padding.  This allows the chunking to work correctly for this
limited case without impacting other use-cases.

Signed-off-by: Jim Wylder 
Link: https://msgid.link/r/20240523211437.2839942-1-jwylder@google.com
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

drivers: core: synchronize really_probe() and dev_uevent()

2024-06-21T12:38:37+00:00

commit c0a40097f0bc81deafc15f9195d1fb54595cd6d0 upstream.

Synchronize the dev->driver usage in really_probe() and dev_uevent().
These can run in different threads, what can result in the following
race condition for dev->driver uninitialization:

Thread #1:
==========

really_probe() {
...
probe_failed:
...
device_unbind_cleanup(dev) {
    ...
    dev->driver = NULL;   // <= Failed probe sets dev->driver to NULL
    ...
    }
...
}

Thread #2:
==========

dev_uevent() {
...
if (dev->driver)
      // If dev->driver is NULLed from really_probe() from here on,
      // after above check, the system crashes
      add_uevent_var(env, "DRIVER=%s", dev->driver->name);
...
}

really_probe() holds the lock, already. So nothing needs to be done
there. dev_uevent() is called with lock held, often, too. But not
always. What implies that we can't add any locking in dev_uevent()
itself. So fix this race by adding the lock to the non-protected
path. This is the path where above race is observed:

 dev_uevent+0x235/0x380
 uevent_show+0x10c/0x1f0  <= Add lock here
 dev_attr_show+0x3a/0xa0
 sysfs_kf_seq_show+0x17c/0x250
 kernfs_seq_show+0x7c/0x90
 seq_read_iter+0x2d7/0x940
 kernfs_fop_read_iter+0xc6/0x310
 vfs_read+0x5bc/0x6b0
 ksys_read+0xeb/0x1b0
 __x64_sys_read+0x42/0x50
 x64_sys_call+0x27ad/0x2d30
 do_syscall_64+0xcd/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Similar cases are reported by syzkaller in

https://syzkaller.appspot.com/bug?extid=ffa8143439596313a85a

But these are regarding the *initialization* of dev->driver

dev->driver = drv;

As this switches dev->driver to non-NULL these reports can be considered
to be false-positives (which should be "fixed" by this commit, as well,
though).

The same issue was reported and tried to be fixed back in 2015 in

https://lore.kernel.org/lkml/1421259054-2574-1-git-send-email-a.sangwan@samsung.com/

already.

Fixes: 239378f16aa1 ("Driver core: add uevent vars for devices of a class")
Cc: stable 
Cc: syzbot+ffa8143439596313a85a@syzkaller.appspotmail.com
Cc: Ashish Sangwan 
Cc: Namjae Jeon 
Signed-off-by: Dirk Behme 
Link: https://lore.kernel.org/r/20240513050634.3964461-1-dirk.behme@de.bosch.com
Signed-off-by: Greg Kroah-Hartman

module: don't ignore sysfs_create_link() failures

2024-06-12T09:12:17+00:00

[ Upstream commit 85d2b0aa170351380be39fe4ff7973df1427fe76 ]

The sysfs_create_link() return code is marked as __must_check, but the
module_add_driver() function tries hard to not care, by assigning the
return code to a variable. When building with 'make W=1', gcc still
warns because this variable is only assigned but not used:

drivers/base/module.c: In function 'module_add_driver':
drivers/base/module.c:36:6: warning: variable 'no_warn' set but not used [-Wunused-but-set-variable]

Rework the code to properly unwind and return the error code to the
caller. My reading of the original code was that it tries to
not fail when the links already exist, so keep ignoring -EEXIST
errors.

Fixes: e17e0f51aeea ("Driver core: show drivers in /sys/module/")
See-also: 4a7fb6363f2d ("add __must_check to device management code")
Signed-off-by: Arnd Bergmann 
Reviewed-by: Luis Chamberlain 
Link: https://lore.kernel.org/r/20240408080616.3911573-1-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

regmap: Add regmap_read_bypassed()

2024-05-17T10:01:59+00:00

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-only mode.

A typical use for this is to keep the cache in cache-only mode until
the hardware has reached a valid state, but one or more status registers
must be polled to determine when this state is reached.

For example, firmware download on the cs35l56 can take several seconds if
there are multiple amps sharing limited bus bandwidth. This is too long
to block in probe() so it is done as a background task. The device must
be soft-reset to reboot the firmware and during this time the registers are
not accessible, so the cache should be in cache-only. But the driver must
poll a register to detect when reboot has completed.

Signed-off-by: Richard Fitzgerald 
Fixes: 8a731fd37f8b ("ASoC: cs35l56: Move utility functions to shared file")
Link: https://msgid.link/r/20240408101803.43183-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

driver core: Introduce device_link_wait_removal()

2024-04-10T14:36:03+00:00

commit 0462c56c290a99a7f03e817ae5b843116dfb575c upstream.

The commit 80dd33cf72d1 ("drivers: base: Fix device link removal")
introduces a workqueue to release the consumer and supplier devices used
in the devlink.
In the job queued, devices are release and in turn, when all the
references to these devices are dropped, the release function of the
device itself is called.

Nothing is present to provide some synchronisation with this workqueue
in order to ensure that all ongoing releasing operations are done and
so, some other operations can be started safely.

For instance, in the following sequence:
  1) of_platform_depopulate()
  2) of_overlay_remove()

During the step 1, devices are released and related devlinks are removed
(jobs pushed in the workqueue).
During the step 2, OF nodes are destroyed but, without any
synchronisation with devlink removal jobs, of_overlay_remove() can raise
warnings related to missing of_node_put():
  ERROR: memory leak, expected refcount 1 instead of 2

Indeed, the missing of_node_put() call is going to be done, too late,
from the workqueue job execution.

Introduce device_link_wait_removal() to offer a way to synchronize
operations waiting for the end of devlink removals (i.e. end of
workqueue jobs).
Also, as a flushing operation is done on the workqueue, the workqueue
used is moved from a system-wide workqueue to a local one.

Cc: stable@vger.kernel.org
Signed-off-by: Herve Codina 
Tested-by: Luca Ceresoli 
Reviewed-by: Nuno Sa 
Reviewed-by: Saravana Kannan 
Acked-by: Greg Kroah-Hartman 
Link: https://lore.kernel.org/r/20240325152140.198219-2-herve.codina@bootlin.com
Signed-off-by: Rob Herring 
Signed-off-by: Greg Kroah-Hartman

regmap: maple: Fix uninitialized symbol 'ret' warnings

2024-04-10T14:36:00+00:00

[ Upstream commit eaa03486d932572dfd1c5f64f9dfebe572ad88c0 ]

Fix warnings reported by smatch by initializing local 'ret' variable
to 0.

drivers/base/regmap/regcache-maple.c:186 regcache_maple_drop()
error: uninitialized symbol 'ret'.
drivers/base/regmap/regcache-maple.c:290 regcache_maple_sync()
error: uninitialized symbol 'ret'.

Signed-off-by: Richard Fitzgerald 
Fixes: f033c26de5a5 ("regmap: Add maple tree based register cache")
Link: https://lore.kernel.org/r/20240329144630.1965159-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regmap: maple: Fix cache corruption in regcache_maple_drop()

2024-04-10T14:35:58+00:00

[ Upstream commit 00bb549d7d63a21532e76e4a334d7807a54d9f31 ]

When keeping the upper end of a cache block entry, the entry[] array
must be indexed by the offset from the base register of the block,
i.e. max - mas.index.

The code was indexing entry[] by only the register address, leading
to an out-of-bounds access that copied some part of the kernel
memory over the cache contents.

This bug was not detected by the regmap KUnit test because it only
tests with a block of registers starting at 0, so mas.index == 0.

Signed-off-by: Richard Fitzgerald 
Fixes: f033c26de5a5 ("regmap: Add maple tree based register cache")
Link: https://msgid.link/r/20240327114406.976986-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

PM: sleep: wakeirq: fix wake irq warning in system suspend

2024-04-03T13:28:24+00:00

[ Upstream commit e7a7681c859643f3f2476b2a28a494877fd89442 ]

When driver uses pm_runtime_force_suspend() as the system suspend callback
function and registers the wake irq with reverse enable ordering, the wake
irq will be re-enabled when entering system suspend, triggering an
'Unbalanced enable for IRQ xxx' warning. In this scenario, the call
sequence during system suspend is as follows:
  suspend_devices_and_enter()
    -> dpm_suspend_start()
      -> dpm_run_callback()
        -> pm_runtime_force_suspend()
          -> dev_pm_enable_wake_irq_check()
          -> dev_pm_enable_wake_irq_complete()

    -> suspend_enter()
      -> dpm_suspend_noirq()
        -> device_wakeup_arm_wake_irqs()
          -> dev_pm_arm_wake_irq()

To fix this issue, complete the setting of WAKE_IRQ_DEDICATED_ENABLED flag
in dev_pm_enable_wake_irq_complete() to avoid redundant irq enablement.

Fixes: 8527beb12087 ("PM: sleep: wakeirq: fix wake irq arming")
Reviewed-by: Dhruva Gole 
Signed-off-by: Qingliang Li 
Reviewed-by: Johan Hovold 
Cc: 5.16+  # 5.16+
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin