CVE-2026-46190

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

mtd: spi-nor: debugfs: fix out-of-bounds read in spi_nor_params_show()

Sashiko noticed an out-of-bounds read [1].

In spi_nor_params_show(), the snor_f_names array is passed to spi_nor_print_flags() using sizeof(snor_f_names).

Since snor_f_names is an array of pointers, sizeof() returns the total number of bytes occupied by the pointers (element_count * sizeof(void *)) rather than the element count itself. On 64-bit systems, this makes the passed length 8x larger than intended.

Inside spi_nor_print_flags(), the names_len argument is used to bounds-check the names array access. An out-of-bounds read occurs if a flag bit is set that exceeds the arrays actual element count but is within the inflated byte-size count.

Correct this by using ARRAY_SIZE() to pass the actual number of string pointers in the array.

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/231b8e1f604f6e0a7e100536f506cdf482e2c5f5
• https://git.kernel.org/stable/c/34bdcfb496b29f9a52431194f94473b37fb8c162
• https://git.kernel.org/stable/c/9a80c458320e0514e11945402dd6e48fcee05524
• https://git.kernel.org/stable/c/c0b654bc0b76a1da102d9138be1ed1223bd99310
• https://git.kernel.org/stable/c/ca18c180b053f6ce80394322b314ac721c316af7
• https://git.kernel.org/stable/c/e47029b977e747cb3a9174308fd55762cce70147