Memory Allocation, Default memory allocation strategy on Linux?

I lately learned about memory allocations and use of malloc. The malloc command is defined in the POSIX standard, as can be seen here It says

The order and contiguity of storage allocated by successive calls to malloc() is unspecified.

So what is the default allocation strategy malloc uses on Linux. Is that allocation strategy different then from windows/ macOS or Android?

I heard malloc on Linux uses the Buddy memory allocation strategy is that true, since on wiki it only says the Linux Kernel uses it, but not Linux itself, idk?