From: Ivan Maidanski <ivmai@mail.ru>
Date: Tue, 10 Apr 2018 07:31:57 +0000 (+0300)
Subject: Avoid potential race in print_static_roots called by dyld_image_add/remove
X-Git-Tag: v8.0.0~247
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=eeab59b3015c8629edeadcf097d0a12515cc8ccd;p=gc

Avoid potential race in print_static_roots called by dyld_image_add/remove

* dyn_load.c [DARWIN && DARWIN_DEBUG && !NO_DEBUGGING]
(GC_dyld_image_add, GC_dyld_image_remove): Place LOCK/UNLOCK around
GC_print_static_roots() call.
* dyn_load.c [DARWIN && DARWIN_DEBUG && !NO_DEBUGGING]
(GC_dyld_image_remove): Add DCL_LOCK_STATE.
---

diff --git a/dyn_load.c b/dyn_load.c
index 7f36b0bb..190dc107 100644
--- a/dyn_load.c
+++ b/dyn_load.c
@@ -1373,8 +1373,10 @@ STATIC void GC_dyld_image_add(const struct GC_MACH_HEADER *hdr,
     }
   }
 
-# ifdef DARWIN_DEBUG
+# if defined(DARWIN_DEBUG) && !defined(NO_DEBUGGING)
+    LOCK();
     GC_print_static_roots();
+    UNLOCK();
 # endif
 }
 
@@ -1385,6 +1387,9 @@ STATIC void GC_dyld_image_remove(const struct GC_MACH_HEADER *hdr,
   unsigned long start, end;
   unsigned i, j;
   const struct GC_MACH_SECTION *sec;
+# if defined(DARWIN_DEBUG) && !defined(NO_DEBUGGING)
+    DCL_LOCK_STATE;
+# endif
 
   for (i = 0; i < sizeof(GC_dyld_sections)/sizeof(GC_dyld_sections[0]); i++) {
     sec = GC_GETSECTBYNAME(hdr, GC_dyld_sections[i].seg,
@@ -1426,8 +1431,10 @@ STATIC void GC_dyld_image_remove(const struct GC_MACH_HEADER *hdr,
     }
   }
 
-# ifdef DARWIN_DEBUG
+# if defined(DARWIN_DEBUG) && !defined(NO_DEBUGGING)
+    LOCK();
     GC_print_static_roots();
+    UNLOCK();
 # endif
 }