CVE Published: 17/05/2024 |
CVE Updated: 05/11/2024 |
CVE Year: 2024 Source: Linux |
Vendor: Linux |
Product: Linux Status : PUBLISHED
CVE-2024-35824 Description
In the Linux kernel, the following vulnerability has been resolved:
misc: lis3lv02d_i2c: Fix regulators getting en-/dis-abled twice on suspend/resume
When not configured for wakeup lis3lv02d_i2c_suspend() will call
lis3lv02d_poweroff() even if the device has already been turned off
by the runtime-suspend handler and if configured for wakeup and
the device is runtime-suspended at this point then it is not turned
back on to serve as a wakeup source.
Before commit b1b9f7a49440 ("misc: lis3lv02d_i2c: Add missing setting
of the reg_ctrl callback"), lis3lv02d_poweroff() failed to disable
the regulators which as a side effect made calling poweroff() twice ok.
Now that poweroff() correctly disables the regulators, doing this twice
triggers a WARN() in the regulator core:
unbalanced disables for regulator-dummy
WARNING: CPU: 1 PID: 92 at drivers/regulator/core.c:2999 _regulator_disable
...
Fix lis3lv02d_i2c_suspend() to not call poweroff() a second time if
already runtime-suspended and add a poweron() call when necessary to
make wakeup work.
lis3lv02d_i2c_resume() has similar issues, with an added weirness that
it always powers on the device if it is runtime suspended, after which
the first runtime-resume will call poweron() again, causing the enabled
count for the regulator to increase by 1 every suspend/resume. These
unbalanced regulator_enable() calls cause the regulator to never
be turned off and trigger the following WARN() on driver unbind:
WARNING: CPU: 1 PID: 1724 at drivers/regulator/core.c:2396 _regulator_put
Fix this by making lis3lv02d_i2c_resume() mirror the new suspend().