CVE-2024-35824 misc: lis3lv02d_i2c: Fix regulators getting en-/dis-abled twice on suspend/resume

2024-05-1713:27:25

Linux

www.cve.org

linux kernel

vulnerability

regulators

suspend/resume

power en-/dis-abling

fix

6.3 Medium

AI Score

Confidence

High

0.0004 Low

EPSS

Percentile

15.7%

JSON

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().

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/misc/lis3lv02d/lis3lv02d_i2c.c"
    ],
    "versions": [
      {
        "version": "2c1164ad927e",
        "lessThan": "4154e7673541",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1229ce1c4acd",
        "lessThan": "997ca4153846",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "755182e1e866",
        "lessThan": "f6df761182fc",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "b1b9f7a49440",
        "lessThan": "ac3e0384073b",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/misc/lis3lv02d/lis3lv02d_i2c.c"
    ],
    "versions": [
      {
        "version": "6.1.77",
        "lessThan": "6.1.84",
        "status": "affected",
        "versionType": "custom"
      },
      {
        "version": "6.6.16",
        "lessThan": "6.6.24",
        "status": "affected",
        "versionType": "custom"
      },
      {
        "version": "6.7.4",
        "lessThan": "6.7.12",
        "status": "affected",
        "versionType": "custom"
      }
    ]
  }
]