diff options
Diffstat (limited to 'libdl')
| -rw-r--r-- | libdl/libdl_cfi.cpp | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/libdl/libdl_cfi.cpp b/libdl/libdl_cfi.cpp index 362b093fa..8458564a8 100644 --- a/libdl/libdl_cfi.cpp +++ b/libdl/libdl_cfi.cpp @@ -29,10 +29,12 @@ static struct { char padding[PAGE_SIZE - sizeof(v)]; } shadow_base_storage alignas(PAGE_SIZE); +// __cfi_init is called by the loader as soon as the shadow is mapped. This may happen very early +// during startup, before libdl.so global constructors, and, on i386, even before __libc_sysinfo is +// initialized. This function should not do any system calls. extern "C" uintptr_t* __cfi_init(uintptr_t shadow_base) { shadow_base_storage.v = shadow_base; static_assert(sizeof(shadow_base_storage) == PAGE_SIZE, ""); - mprotect(&shadow_base_storage, PAGE_SIZE, PROT_READ); return &shadow_base_storage.v; } |