CVE-2021-47384

hwmon: (w83793) Fix NULL pointer dereference by removing unnecessary structure field

State: Published
Severity: 5.3 Medium
Published: May 21, 2024
Updated: May 11, 2026
Reserved: May 21, 2024

Description

In the Linux kernel, the following vulnerability has been resolved:

hwmon: (w83793) Fix NULL pointer dereference by removing unnecessary structure field

If driver read tmp value sufficient for (tmp & 0x08) && (!(tmp & 0x80)) && ((tmp & 0x7) == ((tmp >> 4) & 0x7)) from device then Null pointer dereference occurs. (It is possible if tmp = 0b0xyz1xyz, where same literals mean same numbers) Also lm75[] does not serve a purpose anymore after switching to devm_i2c_new_dummy_device() in w83791d_detect_subclients().

The patch fixes possible NULL pointer dereference by removing lm75[].

Found by Linux Driver Verification project (linuxtesting.org).

[groeck: Dropped unnecessary continuation lines, fixed multi-line alignments]

Scores

CVSS	Score	Vector	Source
3.1	5.3 Medium	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L	CISA-ADP

Weaknesses

The record names no weakness.

Affected Products

Product	Versions
LinuxLinux	cf48d17623281c2b3185030ed23f148bd47e15de to before 6cb01fe630eaffc5a2c3f7364436caddba286623Affected cf48d17623281c2b3185030ed23f148bd47e15de to before 7c4fd5de39f273626a2b0f3a446d2cc85cd47616Affected cf48d17623281c2b3185030ed23f148bd47e15de to before 746011193f44f97f8784edcf8327c587946745fcAffected cf48d17623281c2b3185030ed23f148bd47e15de to before dd4d747ef05addab887dc8ff0d6ab9860bbcd783Affected
LinuxLinux	5.4Affected before 5.4Not affected 5.4.151 through 5.4.Not affected 5.10.71 through 5.10.Not affected 5.14.10 through 5.14.*Not affected 5.15 and laterNot affected

References

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