From 6d0eefdf70135a01476b787df50f34da77ae5529 Mon Sep 17 00:00:00 2001
From: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Date: Thu, 6 Jun 2024 10:53:19 +0100
Subject: [PATCH] target/i386: fix size of EBP writeback in gen_enter()

The calculation of FrameTemp is done using the size indicated by mo_pushpop()
before being written back to EBP, but the final writeback to EBP is done using
the size indicated by mo_stacksize().

In the case where mo_pushpop() is MO_32 and mo_stacksize() is MO_16 then the
final writeback to EBP is done using MO_16 which can leave junk in the top
16-bits of EBP after executing ENTER.

Change the writeback of EBP to use the same size indicated by mo_pushpop() to
ensure that the full value is written back.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2198
Message-ID: <20240606095319.229650-5-mark.cave-ayland@ilande.co.uk>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 3973615e7fbaeef1deeaa067577e373781ced70a)
Signed-off-by: zhujun2 <zhujun2_yewu@cmss.chinamobile.com>
---
 target/i386/tcg/translate.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c
index dc672d7995..19b8250452 100644
--- a/target/i386/tcg/translate.c
+++ b/target/i386/tcg/translate.c
@@ -2661,7 +2661,7 @@ static void gen_enter(DisasContext *s, int esp_addend, int level)
     }
 
     /* Copy the FrameTemp value to EBP.  */
-    gen_op_mov_reg_v(s, a_ot, R_EBP, s->T1);
+    gen_op_mov_reg_v(s, d_ot, R_EBP, s->T1);
 
     /* Compute the final value of ESP.  */
     tcg_gen_subi_tl(s->T1, s->T1, esp_addend + size * level);
-- 
2.41.0.windows.1