diff options
Diffstat (limited to 'winsup/cygwin/mmap.cc')
| -rw-r--r-- | winsup/cygwin/mmap.cc | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/winsup/cygwin/mmap.cc b/winsup/cygwin/mmap.cc index e2a25de52..16611480c 100644 --- a/winsup/cygwin/mmap.cc +++ b/winsup/cygwin/mmap.cc @@ -786,15 +786,31 @@ mprotect (void *addr, size_t len, int prot) return 0; } + /* If write protection is requested, check if the page was + originally protected writecopy. In this case call VirtualProtect + requesting PAGE_WRITECOPY, otherwise the VirtualProtect will fail + on NT version >= 5.0 */ + bool writecopy = false; + if (prot & PROT_WRITE) + { + MEMORY_BASIC_INFORMATION mbi; + if (VirtualQuery (addr, &mbi, sizeof mbi)) + { + if (mbi.AllocationProtect == PAGE_WRITECOPY + || mbi.AllocationProtect == PAGE_EXECUTE_WRITECOPY) + writecopy = true; + } + } + switch (prot) { case PROT_READ | PROT_WRITE | PROT_EXEC: case PROT_WRITE | PROT_EXEC: - new_prot = PAGE_EXECUTE_READWRITE; + new_prot = writecopy ? PAGE_EXECUTE_WRITECOPY : PAGE_EXECUTE_READWRITE; break; case PROT_READ | PROT_WRITE: case PROT_WRITE: - new_prot = PAGE_READWRITE; + new_prot = writecopy ? PAGE_WRITECOPY : PAGE_READWRITE; break; case PROT_READ | PROT_EXEC: new_prot = PAGE_EXECUTE_READ; |