mmap/mmap: Add missing grub_malloc() failure check

This patch adds a NULL check after grub_malloc() call. Missing a failure
check after calling grub_malloc() can lead to undefined behavior. If the
allocation fails and returns NULL subsequent dereferencing or writing to
the pointer will likely result in a runtime error such as a segmentation
fault.

Signed-off-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

diff --git a/grub-core/mmap/mmap.c b/grub-core/mmap/mmap.c
index c8c8312c56f2651db2cdd05f19d7f079d5dccc99..8f03b7765330cf3a2919665f5af5a53719d90398 100644 (file)
--- a/grub-core/mmap/mmap.c
+++ b/grub-core/mmap/mmap.c
@@ -242,6 +242,9 @@ grub_mmap_iterate (grub_memory_hook_t hook, void *hook_data)
          else
            {
              struct mm_list *n = grub_malloc (sizeof (*n));
+              if (n == NULL)
+                return grub_errno;
+
              n->val = ctx.scanline_events[i].memtype;
              n->present = 1;
              n->next = present[ctx.scanline_events[i].priority].next;