[PATCH 04/16] malloc: Simplify __mtag_tag_new_usable

Szabolcs Nagy szabolcs.nagy@arm.com
Thu Mar 4 16:31:18 GMT 2021


The chunk cannot be a dumped one here.  The only non-obvious cases
are free and realloc which may be called on a dumped area chunk,
but in both cases it can be verified that tagging is already
avoided for dumped area chunks.
---
 malloc/arena.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/malloc/arena.c b/malloc/arena.c
index bf17be27d4..0777dc70c6 100644
--- a/malloc/arena.c
+++ b/malloc/arena.c
@@ -298,11 +298,6 @@ __mtag_tag_new_usable (void *ptr)
   if (ptr)
     {
       mchunkptr cp = mem2chunk(ptr);
-      /* This likely will never happen, but we can't handle retagging
-	 chunks from the dumped main arena.  So just return the
-	 existing pointer.  */
-      if (DUMPED_MAIN_ARENA_CHUNK (cp))
-	return ptr;
       ptr = __libc_mtag_tag_region (__libc_mtag_new_tag (ptr),
 				    CHUNK_AVAILABLE_SIZE (cp) - CHUNK_HDR_SZ);
     }
-- 
2.17.1



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