CVE-2023-53465

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

soundwire: qcom: fix storing port config out-of-bounds

The qcom_swrm_ctrl->pconfig has size of QCOM_SDW_MAX_PORTS (14), however we index it starting from 1, not 0, to match real port numbers. This can lead to writing port config past pconfig bounds and overwriting next member of qcom_swrm_ctrl struct. Reported also by smatch:

drivers/soundwire/qcom.c:1269 qcom_swrm_get_port_config() error: buffer overflow ctrl->pconfig 14 <= 14

Weakness

The product reads data past the end, or before the beginning, of the intended buffer.

Affected Software

Potential Mitigations

• Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
• When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
• Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
• To reduce the likelihood of introducing an out-of-bounds read, ensure that you validate and ensure correct calculations for any length argument, buffer size calculation, or offset. Be especially careful of relying on a sentinel (i.e. special character such as NUL) in untrusted inputs.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/540.html

References

• https://git.kernel.org/stable/c/20f7c4d51c94abb1a1a7c21900db4fb5afe5c8ff
• https://git.kernel.org/stable/c/32eb67d7360d48c15883e0d21b29c0aab9da022e
• https://git.kernel.org/stable/c/490937d479abe5f6584e69b96df066bc87be92e9
• https://git.kernel.org/stable/c/801daff0078087b5df9145c9f5e643c28129734b