From: Avnish Chouhan <avnish@linux.ibm.com>
Date: Tue, 28 Oct 2025 16:32:01 +0000 (+0530)
Subject: mmap/mmap: Add missing grub_malloc() failure check
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=77e2ceb79a240d54445355317d2f4569c0550ae2;p=thirdparty%2Fgrub.git

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 c8c8312c5..8f03b7765 100644
--- 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;