Guest descriptors are host C runtime descriptors. Closing descriptor 0, 1
or 2 closed the host process's standard stream, and the runtime then gave
that number to the next file opened anywhere in the process, including
files libkernel opens itself, such as the APR reader's. The title's next
close of the same number closed that file mid-read.
close and sceKernelClose now fail with EBADF for descriptors 0 to 2 that
were open when libkernel loaded, and leave them open. A standard
descriptor that was not open at load can still be opened and closed by
the guest.
PPSA21703 calls sceKernelClose(0) repeatedly while loading asset
bundles, which made APR reads return 0 or a part of the requested bytes
and raised UCRT invalid parameter reports from close.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
