git: 2d67765f10e7 - main - malloc: Use ckdint.h helpers instead of WOULD_OVERFLOW

The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=2d67765f10e7da43ba2d4a7fc074c15d5354684b

commit 2d67765f10e7da43ba2d4a7fc074c15d5354684b
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2026-08-17 18:15:17 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2026-08-17 18:41:36 +0000

    malloc: Use ckdint.h helpers instead of WOULD_OVERFLOW
    
    This serves to demonstrate some usage of the ckdint.h helpers.  The new
    version also generates better machine code on amd64 and arm64.
    
    Reviewed by:    kib, emaste
    MFC after:      2 weeks
    Sponsored by:   The FreeBSD Foundation
---
 sys/kern/kern_malloc.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/sys/kern/kern_malloc.c b/sys/kern/kern_malloc.c
index b0bb4511cb16..ffc260781d60 100644
--- a/sys/kern/kern_malloc.c
+++ b/sys/kern/kern_malloc.c
@@ -43,13 +43,13 @@
  * description.
  */
 
-#include <sys/cdefs.h>
 #include "opt_ddb.h"
 #include "opt_vm.h"
 
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/asan.h>
+#include <sys/ckdint.h>
 #include <sys/kdb.h>
 #include <sys/kernel.h>
 #include <sys/lock.h>
@@ -823,22 +823,24 @@ malloc_domainset_aligned(size_t size, size_t align,
 void *
 mallocarray(size_t nmemb, size_t size, struct malloc_type *type, int flags)
 {
+	size_t n;
 
-	if (WOULD_OVERFLOW(nmemb, size))
+	if (ckd_mul(&n, nmemb, size) != 0)
 		panic("mallocarray: %zu * %zu overflowed", nmemb, size);
 
-	return (malloc(size * nmemb, type, flags));
+	return (malloc(n, type, flags));
 }
 
 void *
 mallocarray_domainset(size_t nmemb, size_t size, struct malloc_type *type,
     struct domainset *ds, int flags)
 {
+	size_t n;
 
-	if (WOULD_OVERFLOW(nmemb, size))
+	if (ckd_mul(&n, nmemb, size) != 0)
 		panic("mallocarray_domainset: %zu * %zu overflowed", nmemb, size);
 
-	return (malloc_domainset(size * nmemb, type, ds, flags));
+	return (malloc_domainset(n, type, ds, flags));
 }
 
 #if defined(INVARIANTS) && !defined(KASAN)