Bug 1403668 - Use SA_ONSTACK for several SIGSEGV handlers. r=ted

MozReview-Commit-ID: IwVYiBF3Ek8

--HG--
extra : rebase_source : 3bbcdee6042aa9e159432c8d0df6f922dba002f1

js/src/ds/MemoryProtectionExceptionHandler.cpp

@@ -282,7 +282,7 @@ MemoryProtectionExceptionHandler::install()
 
     // Install our new exception handler and save the previous one.
     struct sigaction faultHandler = {};
-    faultHandler.sa_flags = SA_SIGINFO | SA_NODEFER;
+    faultHandler.sa_flags = SA_SIGINFO | SA_NODEFER | SA_ONSTACK;
     faultHandler.sa_sigaction = UnixExceptionHandler;
     sigemptyset(&faultHandler.sa_mask);
     sExceptionHandlerInstalled = !sigaction(SIGSEGV, &faultHandler, &sPrevSEGVHandler);

js/src/wasm/WasmSignalHandlers.cpp

@@ -1617,7 +1617,7 @@ ProcessHasSignalHandlers()
 
     // Allow handling OOB with signals on all architectures
     struct sigaction faultHandler;
-    faultHandler.sa_flags = SA_SIGINFO | SA_NODEFER;
+    faultHandler.sa_flags = SA_SIGINFO | SA_NODEFER | SA_ONSTACK;
     faultHandler.sa_sigaction = WasmFaultHandler<Signal::SegFault>;
     sigemptyset(&faultHandler.sa_mask);
     if (sigaction(SIGSEGV, &faultHandler, &sPrevSEGVHandler))
@@ -1626,7 +1626,7 @@ ProcessHasSignalHandlers()
 #  if defined(JS_CODEGEN_ARM)
     // On Arm Handle Unaligned Accesses
     struct sigaction busHandler;
-    busHandler.sa_flags = SA_SIGINFO | SA_NODEFER;
+    busHandler.sa_flags = SA_SIGINFO | SA_NODEFER | SA_ONSTACK;
     busHandler.sa_sigaction = WasmFaultHandler<Signal::BusError>;
     sigemptyset(&busHandler.sa_mask);
     if (sigaction(SIGBUS, &busHandler, &sPrevSIGBUSHandler))

toolkit/profile/nsProfileLock.cpp

@@ -374,7 +374,7 @@ nsresult nsProfileLock::LockWithSymlink(nsIFile *aLockFile, bool aHaveFcntlLock)
                     struct sigaction act, oldact;
 #ifdef SA_SIGINFO
                     act.sa_sigaction = FatalSignalHandler;
-                    act.sa_flags = SA_SIGINFO;
+                    act.sa_flags = SA_SIGINFO | SA_ONSTACK;
 #else
                     act.sa_handler = FatalSignalHandler;
 #endif