git: 1b1d2aea020e - stable/13 - libc: handle zero alignment in memalign()

The branch stable/13 has been updated by emaste:

URL: https://cgit.FreeBSD.org/src/commit/?id=1b1d2aea020e88b3d2076207b13fec3adde42aa9

commit 1b1d2aea020e88b3d2076207b13fec3adde42aa9
Author:     Paul Floyd <pjfloyd@wanadoo.fr>
AuthorDate: 2023-02-24 16:29:01 +0000
Commit:     Ed Maste <emaste@FreeBSD.org>
CommitDate: 2023-03-03 00:23:24 +0000

    libc: handle zero alignment in memalign()
    
    For compatibility with glibc. The previous code would trigger a division
    by zero in roundup() and terminate.  Instead, just pass through to
    malloc() for align == 0.
    
    PR:             269688
    Reviewed by:    imp, mjg
    MFC after:      1 week
    Pull Request:   https://github.com/freebsd/freebsd-src/pull/655
    
    (cherry picked from commit 2c709ee70ade9fd8f77b37917a4169d667dda41d)
---
 lib/libc/gen/memalign.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/lib/libc/gen/memalign.c b/lib/libc/gen/memalign.c
index ff1c967482cd..88feeaef7afd 100644
--- a/lib/libc/gen/memalign.c
+++ b/lib/libc/gen/memalign.c
@@ -36,5 +36,12 @@ __FBSDID("$FreeBSD$");
 void *
 memalign(size_t align, size_t size)
 {
-	return (aligned_alloc(align, roundup(size, align)));
+	/*
+	 * glibc allows align == 0, but that is not valid for roundup.
+	 * Just pass through to malloc in that case.
+	 */
+	if (align != 0)
+		return (aligned_alloc(align, roundup(size, align)));
+	else
+		return (malloc(size));
 }