CVE-2022-49749: i2c: designware: use casting of u64 in clock multiplication to avoid overflow

Vulnerability summary

CVE-2022-49749 is a medium (CVSS 5.5) Integer Overflow or Wraparound vulnerability in linux. EPSS estimates a 0.19% chance of exploitation in the next 30 days, higher than 9.1% of scored vulnerabilities.

Timeline

1. 27-03-2025
   PublishedVulnerability first disclosed.
2. 11-05-2026
   Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: i2c: designware: use casting of u64 in clock multiplication to avoid overflow In functions i2c_dw_scl_lcnt() and i2c_dw_scl_hcnt() may have overflow by depending on the values of the given parameters including the ic_clk. For example in our use case where ic_clk is larger than one million, multiplication of ic_clk * 4700 will result in 32 bit overflow. Add cast of u64 to the calculation to avoid multiplication overflow, and use the corresponding define for divide.

• CWE-190Integer Overflow or WraparoundThe product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.