CVE-2024-46697

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

nfsd: ensure that nfsd4_fattr_args.context is zeroed out

If nfsd4_encode_fattr4 ends up doing a goto out before we get to checking for the security label, then args.context will be set to uninitialized junk on the stack, which well then try to free. Initialize it early.

Weakness

The product does not initialize or incorrectly initializes a resource, which might leave the resource in an unexpected state when it is accessed or used.

Affected Software

Potential Mitigations

• Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
• For example, in Java, if the programmer does not explicitly initialize a variable, then the code could produce a compile-time error (if the variable is local) or automatically initialize the variable to the default value for the variable’s type. In Perl, if explicit initialization is not performed, then a default value of undef is assigned, which is interpreted as 0, false, or an equivalent value depending on the context in which the variable is accessed.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/26.html
• https://cwe.mitre.org/data/definitions/29.html

References

• https://git.kernel.org/stable/c/dd65b324174a64558a16ebbf4c3266e5701185d0
• https://git.kernel.org/stable/c/f58bab6fd4063913bd8321e99874b8239e9ba726