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| author | Daniel Bertalan <dani@danielbertalan.dev> | 2021-12-22 12:43:20 +0100 |
|---|---|---|
| committer | Andreas Kling <kling@serenityos.org> | 2021-12-23 23:08:10 +0100 |
| commit | d1ef8e63f75b18a744ba65105a0e7e0aac56e6c2 (patch) | |
| tree | cb7486ea36fec460845ae538fb7b0e1f94568fea /Userland/Libraries | |
| parent | 77f9272aaf7d882f37567069df13ade5adee9bbf (diff) | |
| download | serenity-d1ef8e63f75b18a744ba65105a0e7e0aac56e6c2.zip | |
LibELF: Use MAP_FIXED_NOREPLACE for address space reservation
This ensures that we don't corrupt our address space if a non-PIE
program's requested address space happens to coincide with memory we
already use.
Diffstat (limited to 'Userland/Libraries')
| -rw-r--r-- | Userland/Libraries/LibELF/DynamicLoader.cpp | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/Userland/Libraries/LibELF/DynamicLoader.cpp b/Userland/Libraries/LibELF/DynamicLoader.cpp index 548ad4b44a..d0332c2f62 100644 --- a/Userland/Libraries/LibELF/DynamicLoader.cpp +++ b/Userland/Libraries/LibELF/DynamicLoader.cpp @@ -292,8 +292,10 @@ void DynamicLoader::load_program_headers() int reservation_mmap_flags = MAP_ANON | MAP_PRIVATE | MAP_NORESERVE; if (m_elf_image.is_dynamic()) reservation_mmap_flags |= MAP_RANDOMIZED; +#ifdef MAP_FIXED_NOREPLACE else - reservation_mmap_flags |= MAP_FIXED; + reservation_mmap_flags |= MAP_FIXED_NOREPLACE; +#endif // First, we make a dummy reservation mapping, in order to allocate enough VM // to hold all regions contiguously in the address space. @@ -309,6 +311,8 @@ void DynamicLoader::load_program_headers() VERIFY_NOT_REACHED(); } + VERIFY(requested_load_address == nullptr || reservation == requested_load_address); + m_base_address = VirtualAddress { reservation }; // Then we unmap the reservation. |