CVE-2023-53241

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

nfsd: call op_release, even when op_func returns an error

For ops with trivial replies, nfsd4_encode_operation will shortcut most of the encoding work and skip to just marshalling up the status. One of the things it skips is calling op_release. This could cause a memory leak in the layoutget codepath if there is an error at an inopportune time.

Have the compound processing engine always call op_release, even when op_func sets an error in op->status. With this change, we also need nfsd4_block_get_device_info_scsi to set the gd_device pointer to NULL on error to avoid a double free.

Weakness

The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.

Affected Software

Potential Mitigations

• Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone.
• For example, glibc in Linux provides protection against free of invalid pointers.
• When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391].
• To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.

References

• https://git.kernel.org/stable/c/15a8b55dbb1ba154d82627547c5761cac884d810
• https://git.kernel.org/stable/c/3d0dcada384af22dec764c8374a2997870ec86ae
• https://git.kernel.org/stable/c/65a33135e91e6dd661ecdf1194b9d90c49ae3570
• https://git.kernel.org/stable/c/b11d8162c24af4a351d21e2c804d25ca493305e3
• https://git.kernel.org/stable/c/b623a8e5d38a69a3ef8644acb1030dd7c7bc28b3