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Improve signals and memory protection

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- Document sigaction()
- Simplify New Technology fork() code
- Testing and many bug fixes for mprotect()
- Distribute Intel Xed ILD in the amalgamation
- Turn Xed enums into defines to avoid DWARF bloat
- Improve polyfilling of SA_SIGINFO on BSDs and fix bugs
- setpgid(getpid(), getpid()) on Windows will ignore CTRL-C
- Work around issues relating to NT mappings being executable
- Permit automatic executable stack override via `ape_stack_pf`
This commit is contained in:
Justine Tunney 2022-04-12 22:11:00 -07:00
parent c95c9d9508
commit f684e348d4
76 changed files with 1844 additions and 1121 deletions
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30
libc/runtime/fork-nt.c
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@ -106,7 +106,6 @@ textwindows void WinMainForked(void) {
struct DirectMap dm;
uint64_t size, upsize;
int64_t reader, writer;
uint32_t flags1, flags2;
struct MemoryInterval *maps;
char16_t fvar[21 + 1 + 21 + 1];
int64_t oncrash, savetsc, savebir;
@ -163,24 +162,21 @@ textwindows void WinMainForked(void) {
size = maps[i].size;
if (maps[i].flags & MAP_PRIVATE) {
upsize = ROUNDUP(size, FRAMESIZE);
if (maps[i].prot & PROT_EXEC) {
flags1 = kNtPageExecuteReadwrite;
flags2 = kNtFileMapWrite | kNtFileMapExecute;
} else {
flags1 = kNtPageReadwrite;
flags2 = kNtFileMapWrite;
}
// we don't need to close the map handle because sys_mmap_nt
// doesn't mark it inheritable across fork() for MAP_PRIVATE
if (!(maps[i].h =
CreateFileMapping(-1, 0, flags1, upsize >> 32, upsize, 0)) ||
!MapViewOfFileEx(maps[i].h, flags2, 0, 0, upsize, addr) ||
if (!(maps[i].h = CreateFileMapping(-1, 0, kNtPageExecuteReadwrite,
upsize >> 32, upsize, 0)) ||
!MapViewOfFileEx(maps[i].h, kNtFileMapWrite | kNtFileMapExecute, 0, 0,
upsize, addr) ||
!ReadAll(reader, addr, size)) {
ExitProcess(44);
}
} else {
// we can however safely inherit MAP_SHARED with zero copy
if (!MapViewOfFileEx(maps[i].h, __nt2prot(maps[i].prot).flags2,
if (!MapViewOfFileEx(maps[i].h,
maps[i].readonlyfile
? kNtFileMapRead | kNtFileMapExecute
: kNtFileMapWrite | kNtFileMapExecute,
maps[i].offset >> 32, maps[i].offset, size, addr)) {
ExitProcess(45);
}
@ -203,11 +199,8 @@ textwindows void WinMainForked(void) {
_mmi.p = maps;
_mmi.n = specialz / sizeof(_mmi.p[0]);
for (i = 0; i < mapcount; ++i) {
if ((maps[i].flags & MAP_PRIVATE) && (~maps[i].prot & PROT_WRITE)) {
VirtualProtect((void *)((uint64_t)maps[i].x << 16),
ROUNDUP(maps[i].size, FRAMESIZE),
__nt2prot(maps[i].prot).flags1, &oldprot);
}
VirtualProtect((void *)((uint64_t)maps[i].x << 16), maps[i].size,
__prot2nt(maps[i].prot, maps[i].iscow), &oldprot);
}
// we're all done reading!
@ -263,8 +256,7 @@ textwindows int sys_fork_nt(void) {
}
#endif
if (ntspawn(GetProgramExecutableName(), args, environ, forkvar,
&kNtIsInheritable, NULL, true,
0 /* kNtCreateNewProcessGroup */, NULL, &startinfo,
&kNtIsInheritable, NULL, true, 0, NULL, &startinfo,
&procinfo) != -1) {
CloseHandle(reader);
CloseHandle(procinfo.hThread);