From: Kees Cook <kees@kernel.org>
Date: Wed, 19 Nov 2025 22:54:43 +0000 (-0800)
Subject: module/decompress: Avoid open-coded kvrealloc()
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=68e85558587e6bbb5c3ea3c8b4c71ab852e4b53e;p=thirdparty%2Flinux.git

module/decompress: Avoid open-coded kvrealloc()

Replace open-coded allocate/copy with kvrealloc().

Signed-off-by: Kees Cook <kees@kernel.org>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
---

diff --git a/kernel/module/decompress.c b/kernel/module/decompress.c
index 474e68f0f0634..36f52a232a120 100644
--- a/kernel/module/decompress.c
+++ b/kernel/module/decompress.c
@@ -17,16 +17,16 @@
 static int module_extend_max_pages(struct load_info *info, unsigned int extent)
 {
 	struct page **new_pages;
+	unsigned int new_max = info->max_pages + extent;
 
-	new_pages = kvmalloc_array(info->max_pages + extent,
-				   sizeof(info->pages), GFP_KERNEL);
+	new_pages = kvrealloc(info->pages,
+			      size_mul(new_max, sizeof(*info->pages)),
+			      GFP_KERNEL);
 	if (!new_pages)
 		return -ENOMEM;
 
-	memcpy(new_pages, info->pages, info->max_pages * sizeof(info->pages));
-	kvfree(info->pages);
 	info->pages = new_pages;
-	info->max_pages += extent;
+	info->max_pages = new_max;
 
 	return 0;
 }