CVE-2024-26912

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

drm/nouveau: fix several DMA buffer leaks

Nouveau manages GSP-RM DMA buffers with nvkm_gsp_mem objects. Several of these buffers are never dealloced. Some of them can be deallocated right after GSP-RM is initialized, but the rest need to stay until the driver unloads.

Also futher bullet-proof these objects by poisoning the buffer and clearing the nvkm_gsp_mem object when it is deallocated. Poisoning the buffer should trigger an error (or crash) from GSP-RM if it tries to access the buffer after weve deallocated it, because we were wrong about when it is safe to deallocate.

Finally, change the mem->size field to a size_t because thats the same type that dma_alloc_coherent expects.

Weakness

The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory.

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/042b5f83841fbf7ce39474412db3b5e4765a7ea7
• https://git.kernel.org/stable/c/6190d4c08897d748dd25f0b78267a90aa1694e15