[U-Boot] [PATCH] malloc: handle free() before gd is set

[Stephen Warren]

On at least Ubuntu Xenial, free() can be called before main(). In this
case, U-Boot won't have set gd, so dereferencing it will crash. Check
whether gd is set before using it.

While at it, apply the same fix to other functions.

Signed-off-by: Stephen Warren <swarren at wwwdotorg.org>
---
 common/dlmalloc.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/common/dlmalloc.c b/common/dlmalloc.c
index 5ea37dfb6e4c..7453e63d6bf4 100644
--- a/common/dlmalloc.c
+++ b/common/dlmalloc.c
@@ -2453,7 +2453,7 @@ void fREe(mem) Void_t* mem;
 
 #ifdef CONFIG_SYS_MALLOC_F_LEN
 	/* free() is a no-op - all the memory will be freed on relocation */
-	if (!(gd->flags & GD_FLG_FULL_MALLOC_INIT))
+	if (gd && !(gd->flags & GD_FLG_FULL_MALLOC_INIT))
 		return;
 #endif
 
@@ -2609,7 +2609,7 @@ Void_t* rEALLOc(oldmem, bytes) Void_t* oldmem; size_t bytes;
   if (oldmem == NULL) return mALLOc(bytes);
 
 #ifdef CONFIG_SYS_MALLOC_F_LEN
-	if (!(gd->flags & GD_FLG_FULL_MALLOC_INIT)) {
+	if (gd && !(gd->flags & GD_FLG_FULL_MALLOC_INIT)) {
 		/* This is harder to support and should not be needed */
 		panic("pre-reloc realloc() is not supported");
 	}
@@ -2985,7 +2985,7 @@ Void_t* cALLOc(n, elem_size) size_t n; size_t elem_size;
   else
   {
 #ifdef CONFIG_SYS_MALLOC_F_LEN
-	if (!(gd->flags & GD_FLG_FULL_MALLOC_INIT)) {
+	if (gd && !(gd->flags & GD_FLG_FULL_MALLOC_INIT)) {
 		MALLOC_ZERO(mem, sz);
 		return mem;
 	}
-- 
2.7.0