lkml.org 
[lkml]   [2022]   [Jul]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 5.15 79/89] x86/xen: Fix initialisation in hypercall_page after rethunk
Date
From: Ben Hutchings <ben@decadent.org.uk>

The hypercall_page is special and the RETs there should not be changed
into rethunk calls (but can have SLS mitigation). Change the initial
instructions to ret + int3 padding, as was done in upstream commit
5b2fc51576ef "x86/ibt,xen: Sprinkle the ENDBR".

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/xen/xen-head.S | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/x86/xen/xen-head.S
+++ b/arch/x86/xen/xen-head.S
@@ -69,9 +69,9 @@ SYM_CODE_END(asm_cpu_bringup_and_idle)
SYM_CODE_START(hypercall_page)
.rept (PAGE_SIZE / 32)
UNWIND_HINT_FUNC
- .skip 31, 0x90
ANNOTATE_UNRET_SAFE
- RET
+ ret
+ .skip 31, 0xcc
.endr

#define HYPERCALL(n) \

\
 
 \ /
  Last update: 2022-07-22 11:31    [W:0.351 / U:0.044 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site