From fed42742e0b33b358610bf62c7474f55e6465205 Mon Sep 17 00:00:00 2001

From: Chet Ramey <chet.ramey@case.edu>

Date: Wed, 17 Nov 2021 16:44:19 -0500

Subject: [PATCH] Bash-5.1 patch 9: fix bash malloc implementation of

 malloc_usable_size

---

 lib/malloc/malloc.c | 13 ++++++-------

 patchlevel.h        |  2 +-

 2 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/lib/malloc/malloc.c b/lib/malloc/malloc.c

index 439f8ef1..92e6efa5 100644

--- a/lib/malloc/malloc.c

+++ b/lib/malloc/malloc.c

@@ -1286,13 +1286,12 @@ malloc_usable_size (mem)

       p = (union mhead *) ap - 1;

     }

-  /* XXX - should we return 0 if ISFREE? */

-  maxbytes = binsize(p->mh_index);

-

-  /* So the usable size is the maximum number of bytes in the bin less the

-     malloc overhead */

-  maxbytes -= MOVERHEAD + MSLOP;

-  return (maxbytes);

+  /* return 0 if ISFREE */

+  if (p->mh_alloc == ISFREE)

+    return 0;

+  

+  /* Since we use bounds checking, the usable size is the last requested size. */

+  return (p->mh_nbytes);

 }

 #if !defined (NO_VALLOC)

diff --git a/patchlevel.h b/patchlevel.h

index 10fde2ee..17586ff7 100644

--- a/patchlevel.h

+++ b/patchlevel.h

@@ -25,6 +25,6 @@

    regexp `^#define[ 	]*PATCHLEVEL', since that's what support/mkversion.sh

    looks for to find the patch level (for the sccs version string). */

-#define PATCHLEVEL 8

+#define PATCHLEVEL 9

 #endif /* _PATCHLEVEL_H_ */

-- 

2.31.1