Fix potential chunk leaks.android-wear-n-preview-3android-wear-n-preview-1android-n-preview-3

Move chunk_dalloc_arena()'s implementation into chunk_dalloc_wrapper(),
so that if the dalloc hook fails, proper decommit/purge/retain cascading
occurs.  This fixes three potential chunk leaks on OOM paths, one during
dss-based chunk allocation, one during chunk header commit (currently
relevant only on Windows), and one during rtree write (e.g. if rtree
node allocation fails).

Merge chunk_purge_arena() into chunk_purge_default() (refactor, no
change to functionality).

Bug: 28590121

(cherry picked from commit 1ae9287a1aec534fa0a805a717f1c4e058ae8433)

Change-Id: Ia21292ab25c65bb7a8aa44077c86545789a9e786

3 files changed, 25 insertions, 44 deletions

diff --git a/src/arena.c b/src/arena.c
index 965c0fe..b7645d8 100644
--- a/src/arena.c
+++ b/src/arena.c
@@ -617,8 +617,8 @@ arena_chunk_alloc_internal_hard(arena_t *arena, chunk_hooks_t *chunk_hooks,
 		/* Commit header. */
 		if (chunk_hooks->commit(chunk, chunksize, 0, map_bias <<
 		    LG_PAGE, arena->ind)) {
-			chunk_dalloc_wrapper(arena, chunk_hooks,
-			    (void *)chunk, chunksize, *commit);
+			chunk_dalloc_wrapper(arena, chunk_hooks, (void *)chunk,
+			    chunksize, *zero, *commit);
 			chunk = NULL;
 		}
 	}
@@ -629,7 +629,7 @@ arena_chunk_alloc_internal_hard(arena_t *arena, chunk_hooks_t *chunk_hooks,
 			    LG_PAGE, arena->ind);
 		}
 		chunk_dalloc_wrapper(arena, chunk_hooks, (void *)chunk,
-		    chunksize, *commit);
+		    chunksize, *zero, *commit);
 		chunk = NULL;
 	}
 
@@ -1024,7 +1024,7 @@ arena_chunk_ralloc_huge_expand_hard(arena_t *arena, chunk_hooks_t *chunk_hooks,
 		malloc_mutex_unlock(&arena->lock);
 	} else if (chunk_hooks->merge(chunk, CHUNK_CEILING(oldsize), nchunk,
 	    cdiff, true, arena->ind)) {
-		chunk_dalloc_arena(arena, chunk_hooks, nchunk, cdiff, *zero,
+		chunk_dalloc_wrapper(arena, chunk_hooks, nchunk, cdiff, *zero,
 		    true);
 		err = true;
 	}
@@ -1050,8 +1050,8 @@ arena_chunk_ralloc_huge_expand(arena_t *arena, void *chunk, size_t oldsize,
 	}
 	arena_nactive_add(arena, udiff >> LG_PAGE);
 
-	err = (chunk_alloc_cache(arena, &arena->chunk_hooks, nchunk, cdiff,
-	    chunksize, zero, true) == NULL);
+	err = (chunk_alloc_cache(arena, &chunk_hooks, nchunk, cdiff, chunksize,
+	    zero, true) == NULL);
 	malloc_mutex_unlock(&arena->lock);
 	if (err) {
 		err = arena_chunk_ralloc_huge_expand_hard(arena, &chunk_hooks,
@@ -1059,7 +1059,7 @@ arena_chunk_ralloc_huge_expand(arena_t *arena, void *chunk, size_t oldsize,
 		    cdiff);
 	} else if (chunk_hooks.merge(chunk, CHUNK_CEILING(oldsize), nchunk,
 	    cdiff, true, arena->ind)) {
-		chunk_dalloc_arena(arena, &chunk_hooks, nchunk, cdiff, *zero,
+		chunk_dalloc_wrapper(arena, &chunk_hooks, nchunk, cdiff, *zero,
 		    true);
 		err = true;
 	}
@@ -1707,7 +1707,7 @@ arena_unstash_purged(arena_t *arena, chunk_hooks_t *chunk_hooks,
 			extent_node_dirty_remove(chunkselm);
 			arena_node_dalloc(arena, chunkselm);
 			chunkselm = chunkselm_next;
-			chunk_dalloc_arena(arena, chunk_hooks, addr, size,
+			chunk_dalloc_wrapper(arena, chunk_hooks, addr, size,
 			    zeroed, committed);
 		} else {
 			arena_chunk_t *chunk =
diff --git a/src/chunk.c b/src/chunk.c
index b179d21..304d4e5 100644
--- a/src/chunk.c
+++ b/src/chunk.c
@@ -425,8 +425,8 @@ chunk_alloc_default(void *new_addr, size_t size, size_t alignment, bool *zero,
 	arena_t *arena;
 
 	arena = chunk_arena_get(arena_ind);
-	ret = chunk_alloc_core(arena, new_addr, size, alignment, zero,
-	    commit, arena->dss_prec);
+	ret = chunk_alloc_core(arena, new_addr, size, alignment, zero, commit,
+	    arena->dss_prec);
 	if (ret == NULL)
 		return (NULL);
 	if (config_valgrind)
@@ -579,8 +579,18 @@ chunk_dalloc_cache(arena_t *arena, chunk_hooks_t *chunk_hooks, void *chunk,
 	arena_maybe_purge(arena);
 }
 
+static bool
+chunk_dalloc_default(void *chunk, size_t size, bool committed,
+    unsigned arena_ind)
+{
+
+	if (!have_dss || !chunk_in_dss(chunk))
+		return (chunk_dalloc_mmap(chunk, size));
+	return (true);
+}
+
 void
-chunk_dalloc_arena(arena_t *arena, chunk_hooks_t *chunk_hooks, void *chunk,
+chunk_dalloc_wrapper(arena_t *arena, chunk_hooks_t *chunk_hooks, void *chunk,
     size_t size, bool zeroed, bool committed)
 {
 
@@ -605,27 +615,6 @@ chunk_dalloc_arena(arena_t *arena, chunk_hooks_t *chunk_hooks, void *chunk,
 }
 
 static bool
-chunk_dalloc_default(void *chunk, size_t size, bool committed,
-    unsigned arena_ind)
-{
-
-	if (!have_dss || !chunk_in_dss(chunk))
-		return (chunk_dalloc_mmap(chunk, size));
-	return (true);
-}
-
-void
-chunk_dalloc_wrapper(arena_t *arena, chunk_hooks_t *chunk_hooks, void *chunk,
-    size_t size, bool committed)
-{
-
-	chunk_hooks_assure_initialized(arena, chunk_hooks);
-	chunk_hooks->dalloc(chunk, size, committed, arena->ind);
-	if (config_valgrind && chunk_hooks->dalloc != chunk_dalloc_default)
-		JEMALLOC_VALGRIND_MAKE_MEM_NOACCESS(chunk, size);
-}
-
-static bool
 chunk_commit_default(void *chunk, size_t size, size_t offset, size_t length,
     unsigned arena_ind)
 {
@@ -643,8 +632,9 @@ chunk_decommit_default(void *chunk, size_t size, size_t offset, size_t length,
 	    length));
 }
 
-bool
-chunk_purge_arena(arena_t *arena, void *chunk, size_t offset, size_t length)
+static bool
+chunk_purge_default(void *chunk, size_t size, size_t offset, size_t length,
+    unsigned arena_ind)
 {
 
 	assert(chunk != NULL);
@@ -657,15 +647,6 @@ chunk_purge_arena(arena_t *arena, void *chunk, size_t offset, size_t length)
 	    length));
 }
 
-static bool
-chunk_purge_default(void *chunk, size_t size, size_t offset, size_t length,
-    unsigned arena_ind)
-{
-
-	return (chunk_purge_arena(chunk_arena_get(arena_ind), chunk, offset,
-	    length));
-}
-
 bool
 chunk_purge_wrapper(arena_t *arena, chunk_hooks_t *chunk_hooks, void *chunk,
     size_t size, size_t offset, size_t length)
diff --git a/src/chunk_dss.c b/src/chunk_dss.c
index 61fc916..943d0e9 100644
--- a/src/chunk_dss.c
+++ b/src/chunk_dss.c
@@ -136,7 +136,7 @@ chunk_alloc_dss(arena_t *arena, void *new_addr, size_t size, size_t alignment,
 					    CHUNK_HOOKS_INITIALIZER;
 					chunk_dalloc_wrapper(arena,
 					    &chunk_hooks, cpad, cpad_size,
-					    true);
+					    false, true);
 				}
 				if (*zero) {
 					JEMALLOC_VALGRIND_MAKE_MEM_UNDEFINED(