hwmon: (sht3x) Fix unaligned accesses

Overview

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

hwmon: (sht3x) Fix unaligned accesses

Sashiko reports:

In sht3x_update_client(), the 16-bit temperature and humidity values are extracted from a stack-allocated byte array using be16_to_cpup(). The pointers passed to this function are calculated as buf and buf + 3. Since the difference between the two pointers is an odd number of bytes, at least one of them is guaranteed to be at an unaligned offset.

This will trigger an alignment fault on strict-alignment architectures such as ARMv5 or SPARC, resulting in a kernel panic.

Fix the problem by using get_unaligned_be16() instead of be16_to_cpup(), and put_unaligned_be16() instead of cpu_to_be16().

Affected

• Linux >= 7c84f7f80d6fcea36246b793d06c3555ca53ddcd < c41fa44be44e452e7aec2081195488d685026761
• Linux >= 7c84f7f80d6fcea36246b793d06c3555ca53ddcd < 81529add4a2e3cca9240e0e2342973d62f88f02e
• Linux >= 7c84f7f80d6fcea36246b793d06c3555ca53ddcd < c498adfd4c3e85306ccdc19b76e639bfc215f0e7
• Linux >= 7c84f7f80d6fcea36246b793d06c3555ca53ddcd < 1fb41650bc3e14d2a5ddb4bb25e96811e5afe881
• Linux >= 7c84f7f80d6fcea36246b793d06c3555ca53ddcd < f46d5ab43a572b84773015a76966f5da56fc1748
• Linux 4.8

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.