Fix unsafe memory access during gent_longlinks

src/H5LS.c

@@ -481,6 +481,10 @@ herr_t H5LSremove_cache(cache_storage_t *LS, cache_t *cache) {
       LOG_DEBUG(-1, "Cache storage space left: %lu bytes\n", LS->mspace_left);
 #endif
 
+      if (cache->path != NULL) {
+        free(cache->path);
+        cache->path = NULL;
+      }
       free(cache);
       cache = NULL;
     }
@@ -511,6 +515,10 @@ herr_t H5LSremove_cache_all(cache_storage_t *LS) {
   while (head != NULL) {
     if (LS->io_node) {
       ret_value = LS->mmap_cls->removeCacheFolder(head->cache->path);
+      if (head->cache->path != NULL) {
+        free(head->cache->path);
+        head->cache->path = NULL;
+      }
       free(head->cache);
       head->cache = NULL;
       head = head->next;

src/H5LS.h

@@ -50,7 +50,7 @@ typedef struct cache_t {
   hsize_t mspace_per_rank_total; // total space per process
   hsize_t mspace_per_rank_left;  // space left per process
   hid_t fd;                      // the associate file
-  char path[255];                // path
+  char *path;                    // dynamically allocated path
   AccessHistory access_history;
 } cache_t;
 
@@ -115,14 +115,14 @@ typedef struct _IO_THREAD {
 // Memory mapped files
 typedef struct _MMAP {
   // for write
-  int fd;          // file handle for write
-  char fname[255]; // full path of the memory mapped file
-  void *obj;       // this will be used for cache data on global storage layer
-  void *buf;       // pointer that map the file to the memory
-  void *tmp_buf;   // temporally buffer, used for parallel read: copy the read
-                   // buffer, return the H5Dread_to_cache function, the back
-                   // ground thread write the data to the SSD.
-  hsize_t offset;  // the offset of the memory map
+  int fd;         // file handle for write
+  char *fname;    // dynamically allocated full path of the memory mapped file
+  void *obj;      // this will be used for cache data on global storage layer
+  void *buf;      // pointer that map the file to the memory
+  void *tmp_buf;  // temporally buffer, used for parallel read: copy the read
+                  // buffer, return the H5Dread_to_cache function, the back
+                  // ground thread write the data to the SSD.
+  hsize_t offset; // the offset of the memory map
 } MMAP;
 
 // Dataset