efi_memory: avoid possible null pointer dereference
Populate the previous memory descriptor node pointer only after it's
parent struct has been initialised. The compiler fixes this logic to
do the right thing, but it is better to have correct code in place.
Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
diff --git a/lib/efi_loader/efi_memory.c b/lib/efi_loader/efi_memory.c
index 9a62864..6c5cc26 100644
--- a/lib/efi_loader/efi_memory.c
+++ b/lib/efi_loader/efi_memory.c
@@ -138,7 +138,7 @@
merge_again = false;
list_for_each(lhandle, &efi_mem) {
struct efi_mem_list *lmem;
- struct efi_mem_desc *prev = &prevmem->desc;
+ struct efi_mem_desc *prev;
struct efi_mem_desc *cur;
uint64_t pages;
@@ -149,6 +149,7 @@
}
cur = &lmem->desc;
+ prev = &prevmem->desc;
if ((desc_get_end(cur) == prev->physical_start) &&
(prev->type == cur->type) &&