1 files changed, 59 insertions, 10 deletions

diff --git a/crypto/rand/rand_win.c b/crypto/rand/rand_win.c
index 00dbe4232cc1..5198351cf34e 100644
--- a/crypto/rand/rand_win.c
+++ b/crypto/rand/rand_win.c
@@ -463,7 +463,7 @@ int RAND_poll(void)
 		PROCESSENTRY32 p;
 		THREADENTRY32 t;
 		MODULEENTRY32 m;
-		DWORD stoptime = 0;
+		DWORD starttime = 0;
 
 		snap = (CREATETOOLHELP32SNAPSHOT)
 			GetProcAddress(kernel, "CreateToolhelp32Snapshot");
@@ -494,12 +494,29 @@ int RAND_poll(void)
                          * each entry.  Consider each field a source of 1 byte
                          * of entropy.
                          */
+			ZeroMemory(&hlist, sizeof(HEAPLIST32));
 			hlist.dwSize = sizeof(HEAPLIST32);		
-			if (good) stoptime = GetTickCount() + MAXDELAY;
+			if (good) starttime = GetTickCount();
+#ifdef _MSC_VER
 			if (heaplist_first(handle, &hlist))
+				{
+				/*
+				   following discussion on dev ML, exception on WinCE (or other Win
+				   platform) is theoretically of unknown origin; prevent infinite
+				   loop here when this theoretical case occurs; otherwise cope with
+				   the expected (MSDN documented) exception-throwing behaviour of
+				   Heap32Next() on WinCE.
+
+				   based on patch in original message by Tanguy Fautré (2009/03/02)
+			           Subject: RAND_poll() and CreateToolhelp32Snapshot() stability
+			     */
+				int ex_cnt_limit = 42; 
 				do
 					{
 					RAND_add(&hlist, hlist.dwSize, 3);
+					__try
+						{
+						ZeroMemory(&hentry, sizeof(HEAPENTRY32));
 					hentry.dwSize = sizeof(HEAPENTRY32);
 					if (heap_first(&hentry,
 						hlist.th32ProcessID,
@@ -510,10 +527,42 @@ int RAND_poll(void)
 							RAND_add(&hentry,
 								hentry.dwSize, 5);
 						while (heap_next(&hentry)
+						&& (!good || (GetTickCount()-starttime)<MAXDELAY)
 							&& --entrycnt > 0);
 						}
-					} while (heaplist_next(handle,
-						&hlist) && GetTickCount() < stoptime);
+						}
+					__except (EXCEPTION_EXECUTE_HANDLER)
+						{
+							/* ignore access violations when walking the heap list */
+							ex_cnt_limit--;
+						}
+					} while (heaplist_next(handle, &hlist) 
+						&& (!good || (GetTickCount()-starttime)<MAXDELAY)
+						&& ex_cnt_limit > 0);
+				}
+
+#else
+			if (heaplist_first(handle, &hlist))
+				{
+				do
+					{
+					RAND_add(&hlist, hlist.dwSize, 3);
+					hentry.dwSize = sizeof(HEAPENTRY32);
+					if (heap_first(&hentry,
+						hlist.th32ProcessID,
+						hlist.th32HeapID))
+						{
+						int entrycnt = 80;
+						do
+							RAND_add(&hentry,
+								hentry.dwSize, 5);
+						while (heap_next(&hentry)
+							&& --entrycnt > 0);
+						}
+					} while (heaplist_next(handle, &hlist) 
+						&& (!good || (GetTickCount()-starttime)<MAXDELAY));
+				}
+#endif
 
 			/* process walking */
                         /* PROCESSENTRY32 contains 9 fields that will change
@@ -522,11 +571,11 @@ int RAND_poll(void)
                          */
 			p.dwSize = sizeof(PROCESSENTRY32);
 		
-			if (good) stoptime = GetTickCount() + MAXDELAY;
+			if (good) starttime = GetTickCount();
 			if (process_first(handle, &p))
 				do
 					RAND_add(&p, p.dwSize, 9);
-				while (process_next(handle, &p) && GetTickCount() < stoptime);
+				while (process_next(handle, &p) && (!good || (GetTickCount()-starttime)<MAXDELAY));
 
 			/* thread walking */
                         /* THREADENTRY32 contains 6 fields that will change
@@ -534,11 +583,11 @@ int RAND_poll(void)
                          * 1 byte of entropy.
                          */
 			t.dwSize = sizeof(THREADENTRY32);
-			if (good) stoptime = GetTickCount() + MAXDELAY;
+			if (good) starttime = GetTickCount();
 			if (thread_first(handle, &t))
 				do
 					RAND_add(&t, t.dwSize, 6);
-				while (thread_next(handle, &t) && GetTickCount() < stoptime);
+				while (thread_next(handle, &t) && (!good || (GetTickCount()-starttime)<MAXDELAY));
 
 			/* module walking */
                         /* MODULEENTRY32 contains 9 fields that will change
@@ -546,12 +595,12 @@ int RAND_poll(void)
                          * 1 byte of entropy.
                          */
 			m.dwSize = sizeof(MODULEENTRY32);
-			if (good) stoptime = GetTickCount() + MAXDELAY;
+			if (good) starttime = GetTickCount();
 			if (module_first(handle, &m))
 				do
 					RAND_add(&m, m.dwSize, 9);
 				while (module_next(handle, &m)
-					       	&& (GetTickCount() < stoptime));
+					       	&& (!good || (GetTickCount()-starttime)<MAXDELAY));
 			if (close_snap)
 				close_snap(handle);
 			else