linux-stable.git/drivers/base, branch v6.6.98

x86/bugs: Add a Transient Scheduler Attacks mitigation

2025-07-10T14:03:21+00:00

Commit d8010d4ba43e9f790925375a7de100604a5e2dba upstream.

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

Co-developed-by: Kim Phillips 
Signed-off-by: Kim Phillips 
Signed-off-by: Borislav Petkov (AMD) 
Reviewed-by: Pawan Gupta 
Signed-off-by: Greg Kroah-Hartman

software node: Correct a OOB check in software_node_get_reference_args()

2025-06-27T10:08:56+00:00

[ Upstream commit 31e4e12e0e9609850cefd4b2e1adf782f56337d6 ]

software_node_get_reference_args() wants to get @index-th element, so
the property value requires at least '(index + 1) * sizeof(*ref)' bytes
but that can not be guaranteed by current OOB check, and may cause OOB
for malformed property.

Fix by using as OOB check '((index + 1) * sizeof(*ref) > prop->length)'.

Reviewed-by: Sakari Ailus 
Signed-off-by: Zijun Hu 
Link: https://lore.kernel.org/r/20250414-fix_swnode-v2-1-9c9e6ae11eab@quicinc.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

PM: runtime: fix denying of auto suspend in pm_suspend_timer_fn()

2025-06-27T10:08:52+00:00

[ Upstream commit 40d3b40dce375d6f1c1dbf08d79eed3aed6c691d ]

pm_runtime_put_autosuspend() schedules a hrtimer to expire
at "dev->power.timer_expires". If the hrtimer's callback,
pm_suspend_timer_fn(), observes that the current time equals
"dev->power.timer_expires", it unexpectedly bails out instead of
proceeding with runtime suspend.

pm_suspend_timer_fn():

 if (expires > 0 && expires < ktime_get_mono_fast_ns()) {
 	dev->power.timer_expires = 0;
 	rpm_suspend(..)
 }

Additionally, as ->timer_expires is not cleared, all the future auto
suspend requests will not schedule hrtimer to perform auto suspend.

rpm_suspend():

 if ((rpmflags & RPM_AUTO) &&...) {
 	if (!(dev->power.timer_expires && ...) { <-- this will fail.
 		hrtimer_start_range_ns(&dev->power.suspend_timer,...);
 	}
 }

Fix this by as well checking if current time reaches the set expiration.

Co-developed-by: Patrick Daly 
Signed-off-by: Patrick Daly 
Signed-off-by: Charan Teja Kalla 
Link: https://patch.msgid.link/20250515064125.1211561-1-quic_charante@quicinc.com
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

pmdomain: core: Fix error checking in genpd_dev_pm_attach_by_id()

2025-06-19T13:28:36+00:00

[ Upstream commit 0f5757667ec0aaf2456c3b76fcf0c6c3ea3591fe ]

The error checking for of_count_phandle_with_args() does not handle
negative error codes correctly.  The problem is that "index" is a u32 so
in the condition "if (index >= num_domains)" negative error codes stored
in "num_domains" are type promoted to very high positive values and
"index" is always going to be valid.

Test for negative error codes first and then test if "index" is valid.

Fixes: 3ccf3f0cd197 ("PM / Domains: Enable genpd_dev_pm_attach_by_id|name() for single PM domain")
Signed-off-by: Dan Carpenter 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/aBxPQ8AI8N5v-7rL@stanley.mountain
Signed-off-by: Ulf Hansson 
Signed-off-by: Sasha Levin

PM: sleep: Fix power.is_suspended cleanup for direct-complete devices

2025-06-19T13:28:34+00:00

[ Upstream commit d46c4c839c20a599a0eb8d73708ce401f9c7d06d ]

Commit 03f1444016b7 ("PM: sleep: Fix handling devices with direct_complete
set on errors") caused power.is_suspended to be set for devices with
power.direct_complete set, but it forgot to ensure the clearing of that
flag for them in device_resume(), so power.is_suspended is still set for
them during the next system suspend-resume cycle.

If that cycle is aborted in dpm_suspend(), the subsequent invocation of
dpm_resume() will trigger a device_resume() call for every device and
because power.is_suspended is set for the devices in question, they will
not be skipped by device_resume() as expected which causes scary error
messages to be logged (as appropriate).

To address this issue, move the clearing of power.is_suspended in
device_resume() immediately after the power.is_suspended check so it
will be always cleared for all devices processed by that function.

Fixes: 03f1444016b7 ("PM: sleep: Fix handling devices with direct_complete set on errors")
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4280
Reported-and-tested-by: Chris Bainbridge 
Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Mario Limonciello 
Link: https://patch.msgid.link/4990586.GXAFRqVoOG@rjwysocki.net
Signed-off-by: Sasha Levin

x86/its: Enable Indirect Target Selection mitigation

2025-05-18T06:24:11+00:00

commit f4818881c47fd91fcb6d62373c57c7844e3de1c0 upstream.

Indirect Target Selection (ITS) is a bug in some pre-ADL Intel CPUs with
eIBRS. It affects prediction of indirect branch and RETs in the
lower half of cacheline. Due to ITS such branches may get wrongly predicted
to a target of (direct or indirect) branch that is located in the upper
half of the cacheline.

Scope of impact
===============

Guest/host isolation
--------------------
When eIBRS is used for guest/host isolation, the indirect branches in the
VMM may still be predicted with targets corresponding to branches in the
guest.

Intra-mode
----------
cBPF or other native gadgets can be used for intra-mode training and
disclosure using ITS.

User/kernel isolation
---------------------
When eIBRS is enabled user/kernel isolation is not impacted.

Indirect Branch Prediction Barrier (IBPB)
-----------------------------------------
After an IBPB, indirect branches may be predicted with targets
corresponding to direct branches which were executed prior to IBPB. This is
mitigated by a microcode update.

Add cmdline parameter indirect_target_selection=off|on|force to control the
mitigation to relocate the affected branches to an ITS-safe thunk i.e.
located in the upper half of cacheline. Also add the sysfs reporting.

When retpoline mitigation is deployed, ITS safe-thunks are not needed,
because retpoline sequence is already ITS-safe. Similarly, when call depth
tracking (CDT) mitigation is deployed (retbleed=stuff), ITS safe return
thunk is not used, as CDT prevents RSB-underflow.

To not overcomplicate things, ITS mitigation is not supported with
spectre-v2 lfence;jmp mitigation. Moreover, it is less practical to deploy
lfence;jmp mitigation on ITS affected parts anyways.

Signed-off-by: Pawan Gupta 
Signed-off-by: Dave Hansen 
Reviewed-by: Josh Poimboeuf 
Reviewed-by: Alexandre Chartre 
Signed-off-by: Greg Kroah-Hartman

drivers: base: handle module_kobject creation

2025-05-09T07:44:07+00:00

[ Upstream commit f95bbfe18512c5c018720468959edac056a17196 ]

module_add_driver() relies on module_kset list for
/sys/module//drivers directory creation.

Since,
commit 96a1a2412acba ("kernel/params.c: defer most of param_sysfs_init() to late_initcall time")
drivers which are initialized from subsys_initcall() or any other
higher precedence initcall couldn't find the related kobject entry
in the module_kset list because module_kset is not fully populated
by the time module_add_driver() refers it. As a consequence,
module_add_driver() returns early without calling make_driver_name().
Therefore, /sys/module//drivers is never created.

Fix this issue by letting module_add_driver() handle module_kobject
creation itself.

Fixes: 96a1a2412acb ("kernel/params.c: defer most of param_sysfs_init() to late_initcall time")
Cc: stable@vger.kernel.org # requires all other patches from the series
Suggested-by: Rasmus Villemoes 
Signed-off-by: Shyam Saini 
Acked-by: Greg Kroah-Hartman 
Link: https://lore.kernel.org/r/20250227184930.34163-5-shyamsaini@linux.microsoft.com
Signed-off-by: Petr Pavlu 
Signed-off-by: Sasha Levin

driver core: fix potential NULL pointer dereference in dev_uevent()

2025-05-02T05:51:03+00:00

commit 18daa52418e7e4629ed1703b64777294209d2622 upstream.

If userspace reads "uevent" device attribute at the same time as another
threads unbinds the device from its driver, change to dev->driver from a
valid pointer to NULL may result in crash. Fix this by using READ_ONCE()
when fetching the pointer, and take bus' drivers klist lock to make sure
driver instance will not disappear while we access it.

Use WRITE_ONCE() when setting the driver pointer to ensure there is no
tearing.

Signed-off-by: Dmitry Torokhov 
Reviewed-by: Masami Hiramatsu (Google) 
Link: https://lore.kernel.org/r/20250311052417.1846985-3-dmitry.torokhov@gmail.com
Signed-off-by: Greg Kroah-Hartman

driver core: introduce device_set_driver() helper

2025-05-02T05:51:03+00:00

commit 04d3e5461c1f5cf8eec964ab64948ebed826e95e upstream.

In preparation to closing a race when reading driver pointer in
dev_uevent() code, instead of setting device->driver pointer directly
introduce device_set_driver() helper.

Signed-off-by: Dmitry Torokhov 
Reviewed-by: Masami Hiramatsu (Google) 
Link: https://lore.kernel.org/r/20250311052417.1846985-2-dmitry.torokhov@gmail.com
Signed-off-by: Greg Kroah-Hartman

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

2025-05-02T05:51:02+00:00

commit dc1771f718548f7d4b93991b174c6e7b5e1ba410 upstream.

This reverts commit c0a40097f0bc81deafc15f9195d1fb54595cd6d0.

Probing a device can take arbitrary long time. In the field we observed
that, for example, probing a bad micro-SD cards in an external USB card
reader (or maybe cards were good but cables were flaky) sometimes takes
longer than 2 minutes due to multiple retries at various levels of the
stack. We can not block uevent_show() method for that long because udev
is reading that attribute very often and that blocks udev and interferes
with booting of the system.

The change that introduced locking was concerned with dev_uevent()
racing with unbinding the driver. However we can handle it without
locking (which will be done in subsequent patch).

There was also claim that synchronization with probe() is needed to
properly load USB drivers, however this is a red herring: the change
adding the lock was introduced in May of last year and USB loading and
probing worked properly for many years before that.

Revert the harmful locking.

Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov 
Reviewed-by: Masami Hiramatsu (Google) 
Link: https://lore.kernel.org/r/20250311052417.1846985-1-dmitry.torokhov@gmail.com
Signed-off-by: Greg Kroah-Hartman