linux-kernel - [RFC PATCH v4 37/37] arm64: kvm: Annotate stack state for guest enter/exit code

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 29 Apr 2022 17:43:55 +0800
From:   Chen Zhongjin <chenzhongjin@...wei.com>
To:     <linux-kernel@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-arch@...r.kernel.org>
CC:     <jthierry@...hat.com>, <catalin.marinas@....com>,
        <will@...nel.org>, <masahiroy@...nel.org>, <jpoimboe@...hat.com>,
        <peterz@...radead.org>, <ycote@...hat.com>,
        <herbert@...dor.apana.org.au>, <mark.rutland@....com>,
        <davem@...emloft.net>, <ardb@...nel.org>, <maz@...nel.org>,
        <tglx@...utronix.de>, <luc.vanoostenryck@...il.com>,
        <chenzhongjin@...wei.com>
Subject: [RFC PATCH v4 37/37] arm64: kvm: Annotate stack state for guest enter/exit code

From: Julien Thierry <jthierry@...hat.com>

Symbol __guest_enter is called from C code, with a valid stack pointer.

Symbol __guest_exit is reached when resuming EL2 execution, and the
previous stack pointer gets restored.

Add adequate unwind hints.

Signed-off-by: Julien Thierry <jthierry@...hat.com>
---
 arch/arm64/kvm/hyp/entry.S | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S
index 045d4481c820..0c621b8389e2 100644
--- a/arch/arm64/kvm/hyp/entry.S
+++ b/arch/arm64/kvm/hyp/entry.S
@@ -15,6 +15,7 @@
 #include <asm/kvm_mmu.h>
 #include <asm/kvm_mte.h>
 #include <asm/kvm_ptrauth.h>
+#include <asm/unwind_hints.h>
 
 	.text
 
@@ -22,6 +23,7 @@
  * u64 __guest_enter(struct kvm_vcpu *vcpu);
  */
 SYM_CODE_START(__guest_enter)
+	UNWIND_HINT_FUNC
 	// x0: vcpu
 	// x1-x17: clobbered by macros
 	// x29: guest context
@@ -110,6 +112,7 @@ SYM_INNER_LABEL(__guest_exit, SYM_L_GLOBAL)
 	// x1: vcpu
 	// x2-x29,lr: vcpu regs
 	// vcpu x0-x1 on the stack
+	UNWIND_HINT_FUNC sp_offset=16
 
 	add	x1, x1, #VCPU_CONTEXT
 
-- 
2.17.1