Discard sections with pseudo-paths except heap in register_map_entries

If USE_PROC_FOR_LIBRARIES, this commit prevents addition of special
writable sections (from proc maps) like stacks.

* dyn_load.c [(SCO_ELF || DGUX || HURD || NACL || __ELF__ && (LINUX
|| FREEBSD || NETBSD || OPENBSD)) && USE_PROC_FOR_LIBRARIES]
(GC_register_map_entries): Declare path local variable and pass it to
GC_parse_map_entry; discard writable section if its path (mapping name)
starts with '[' but does not match "[heap]".

1 files changed, 5 insertions, 2 deletions

diff --git a/dyn_load.c b/dyn_load.c
index 82aec824..f14242f9 100644
--- a/dyn_load.c
+++ b/dyn_load.c
@@ -309,7 +309,7 @@ static void sort_heap_sects(struct HeapSect *base, size_t number_of_elements)
 
 STATIC void GC_register_map_entries(const char *maps)
 {
-    const char *prot;
+    const char *prot, *path;
     ptr_t start, end;
     unsigned int maj_dev;
     ptr_t least_ha, greatest_ha;
@@ -322,7 +322,7 @@ STATIC void GC_register_map_entries(const char *maps)
                   + GC_our_memory[GC_n_memory-1].hs_bytes;
 
     for (;;) {
-        maps = GC_parse_map_entry(maps, &start, &end, &prot, &maj_dev, 0);
+        maps = GC_parse_map_entry(maps, &start, &end, &prot, &maj_dev, &path);
         if (NULL == maps) break;
 
         if (prot[1] == 'w') {
@@ -334,6 +334,9 @@ STATIC void GC_register_map_entries(const char *maps)
                 /* Stack mapping; discard       */
                 continue;
             }
+            if (path[0] == '[' && strncmp(path+1, "heap]", 5) != 0)
+              continue; /* discard if a pseudo-path unless "[heap]" */
+
 #           ifdef THREADS
               /* This may fail, since a thread may already be           */
               /* unregistered, but its thread stack may still be there. */