CVE-2021-47655

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

media: venus: vdec: fixed possible memory leak issue

The venus_helper_alloc_dpb_bufs() implementation allows an early return on an error path when checking the id from ida_alloc_min() which would not release the earlier buffer allocation.

Move the direct kfree() from the error checking of dma_alloc_attrs() to the common fail path to ensure that allocations are released on all error paths in this function.

Addresses-Coverity: 1494120 (Resource leak)

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/55bccafc246b2e64763a155ec454470c07a54a6e
• https://git.kernel.org/stable/c/5cedfe8aaf1875a5305897107b7f298db4260019
• https://git.kernel.org/stable/c/5f89d05ba93df9c2cdfe493843f93288e55e99eb
• https://git.kernel.org/stable/c/8403fdd775858a7bf04868d43daea0acbe49ddfc