Avoid stack overflows (happened invoking emacs scripts)

jacereda · Jan 31, 2022 · 9b81c5d · 9b81c5d
1 parent b663992
commit 9b81c5d
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Showing 4 changed files with 52 additions and 46 deletions.
diff --git a/Makefile b/Makefile
@@ -11,15 +11,16 @@ CPPFLAGS32=-D_WIN32_WINNT=0x600 -DIS32=1 -isystem$(ROOT32)\i686-w64-mingw32\incl
 OSSRCS=src/win/inject.c src/win/dbg.c
 LDOBJS=$(ROOT64)\x86_64-w64-mingw32\lib\CRT_noglob.o
 INSTALLDIR=$(APPDATA)\local\bin
-
+LDFLAGS=-s
+LDFLAGS32=-s
+LDFLAGS64=-s
 else
 
 PLAT=unix
 CPPFLAGS=-D_GNU_SOURCE -D_DEFAULT_SOURCE=1
 LDFLAGS=-g
 
 OS=$(shell uname -s)
-LS=$(shell which ls)
 
 ifeq ($(OS),Linux)
 LDLIBS=-ldl -lrt
@@ -29,7 +30,9 @@ INSTALLDIR=$(HOME)/.local/bin
 
 endif
 
-CFLAGS+= -g -std=c99 -Wall -O2 -fomit-frame-pointer -fno-stack-protector -MMD
+LS=$(shell which ls)
+
+CFLAGS+= -std=c99 -Wall -O2 -fomit-frame-pointer -fno-stack-protector -MMD
 
 SRCS=src/fsatrace.c src/$(PLAT)/proc.c src/$(PLAT)/shm.c $(OSSRCS)
 

diff --git a/src/fsatrace.c b/src/fsatrace.c
@@ -95,6 +95,20 @@ uniq(char *d, size_t *tot, const char *s, const char *last, size_t lastsz)
 		uniq(d, tot, end + 1, last, lastsz);
 }
 
+static void
+workaround(const char *oenv, size_t buf_size)
+{
+#ifdef _WIN32
+	// Workaround, bash distributed with ghc 8.6.5 seems to discard
+	// most environment variables, pass environment variables as the
+	// first few PATH components.
+	char env[65536];
+	snprintf(env, sizeof(env), "PATH=%s;%ld;%s", oenv, (long)buf_size,
+	    getenv("PATH"));
+	putenv(env);
+#endif
+}
+
 int
 main(int argc, char *const argv[])
 {
@@ -141,17 +155,7 @@ main(int argc, char *const argv[])
 	snprintf(
 	    envbufsize, sizeof(envbufsize), ENVBUFSIZE "=%ld", (long)buf_size);
 	putenv(envbufsize);
-#ifdef _WIN32
-	{
-		// Workaround, bash distributed with ghc 8.6.5 seems to discard
-		// most environment variables, pass environment variables as the
-		// first few PATH components.
-		char env[65536];
-		snprintf(env, sizeof(env), "PATH=%s;%ld;%s", out,
-		    (long)buf_size, getenv("PATH"));
-		putenv(env);
-	}
-#endif
+	workaround(out, buf_size);
 	fflush(stdout);
 	opts = (const unsigned char *)argv[1];
 	bopts = shm.buf + 4;

diff --git a/src/win/fsatracedll.c b/src/win/fsatracedll.c
@@ -18,6 +18,34 @@ resolve(const char *name)
 	return ret;
 }
 
+static void
+dlldeps()
+{
+	// DLLs that were loaded before we got hooked, so mark
+	// them as a read dependency
+	DWORD	cb = 0;
+	wchar_t winBuf[PATH_MAX];
+	char	utfBuf[PATH_MAX];
+	HANDLE	hProcess = GetCurrentProcess();
+	HMODULE modules[8000]; // Pick a huge value to make sure
+			       // we pick up everything
+	if (EnumProcessModules(hProcess, modules, sizeof(modules), &cb)) {
+		// If the buffer we passed was too small, just
+		// ignore it
+		if (sizeof(modules) >= cb) {
+			for (int i = 0; i < cb / sizeof(HMODULE); i++) {
+				DWORD res = GetModuleFileNameExW(
+				    hProcess, modules[i], winBuf, PATH_MAX);
+				if (res != 0)
+					emitOp('r',
+					    utf8PathFromWide(
+						utfBuf, winBuf, res),
+					    0);
+			}
+		}
+	}
+}
+
 INT APIENTRY
 DllMain(HMODULE hDLL, DWORD Reason, LPVOID Reserved)
 {
@@ -26,36 +54,7 @@ DllMain(HMODULE hDLL, DWORD Reason, LPVOID Reserved)
 	switch (Reason) {
 	case DLL_PROCESS_ATTACH:
 		emitInit();
-		{
-			// DLLs that were loaded before we got hooked, so mark
-			// them as a read dependency
-			DWORD	cb = 0;
-			wchar_t winBuf[PATH_MAX];
-			char	utfBuf[PATH_MAX];
-			HANDLE	hProcess = GetCurrentProcess();
-			HMODULE modules[8000]; // Pick a huge value to make sure
-					       // we pick up everything
-			if (EnumProcessModules(
-				hProcess, modules, sizeof(modules), &cb)) {
-				// If the buffer we passed was too small, just
-				// ignore it
-				if (sizeof(modules) >= cb) {
-					for (int i = 0;
-					     i < cb / sizeof(HMODULE); i++) {
-						DWORD res =
-						    GetModuleFileNameExW(
-							hProcess, modules[i],
-							winBuf, PATH_MAX);
-						if (res != 0)
-							emitOp('r',
-							    utf8PathFromWide(
-								utfBuf, winBuf,
-								res),
-							    0);
-					}
-				}
-			}
-		}
+		dlldeps();
 		patchInit();
 		hooksInit(resolve);
 		break;

diff --git a/win.mk b/win.mk
@@ -15,10 +15,10 @@ all: fsatest32.exe
 	$(CC32) -c $(CPPFLAGS32) $(CFLAGS) -march=i686 $< -o $@
 
 fsatracehelper.exe: $(HELPER_OBJ)
-	$(CC32) $< -o $@
+	$(CC32) $(LDFLAGS) $< -o $@
 
 fsatest32.exe: src/fsatest32.o
-	$(CC32) $< -o $@
+	$(CC32) $(LDFLAGS) $< -o $@
 
 fsatrace64.dll: $(OBJS64)
 	$(CC) -shared $(LDFLAGS64) $^ -o $@ $(LDLIBS)