Kernel: Make allocate_randomized() work for 64-bit addresses

The odds of finding a suitable address in 1000 attempts were not in our favor given the size of the 64-bit address space.
Author: https://github.com/gunnarbeutner Commit: https://github.com/SerenityOS/serenity/commit/357ddd393eb Pull-request: https://github.com/SerenityOS/serenity/pull/8795 Reviewed-by: https://github.com/Hendiadyoin1
2021-07-18 02:48:35 +02:00 · 2021-07-18 02:48:35 +02:00 · 357ddd393e · 2024-07-18 08:48:22 +09:00
commit 357ddd393e
parent f0c4941beb
1 changed files with 1 additions and 1 deletions
--- a/Kernel/VM/RangeAllocator.cpp
+++ b/Kernel/VM/RangeAllocator.cpp
@ -67,7 +67,7 @@ Optional<Range> RangeAllocator::allocate_randomized(size_t size, size_t alignmen
    // FIXME: I'm sure there's a smarter way to do this.
    static constexpr size_t maximum_randomization_attempts = 1000;
    for (size_t i = 0; i < maximum_randomization_attempts; ++i) {
-        VirtualAddress random_address { round_up_to_power_of_two(get_fast_random<FlatPtr>(), alignment) };
+        VirtualAddress random_address { round_up_to_power_of_two(get_fast_random<FlatPtr>() % m_total_range.end().get(), alignment) };

        if (!m_total_range.contains(random_address, size))
            continue;