From: Szabolcs Nagy <szabolcs.nagy@arm.com>
Date: Fri, 25 Jun 2021 18:58:59 +0000 (+0100)
Subject: arm: align stack in clone [BZ 28020]
X-Git-Tag: glibc-2.34~179
X-Git-Url: https://sourceware.org/git/?a=commitdiff_plain;h=3101b967874fb7d54a23f75fe93c310143e64af6;p=glibc.git

arm: align stack in clone [BZ 28020]

The arm PCS requires 8 byte aligned stack at function entry.
Previously unaligned stack could crash the clone child.

Fixes bug 28020.
---

diff --git a/sysdeps/unix/sysv/linux/arm/clone.S b/sysdeps/unix/sysv/linux/arm/clone.S
index 44eefee3fc..05596cb7a5 100644
--- a/sysdeps/unix/sysv/linux/arm/clone.S
+++ b/sysdeps/unix/sysv/linux/arm/clone.S
@@ -31,6 +31,8 @@
 ENTRY(__clone)
 	@ sanity check args
 	cmp	r0, #0
+	@ align sp
+	and	r1, r1, #-8
 	ite	ne
 	cmpne	r1, #0
 	moveq	r0, #-EINVAL