linux-kernel - [tip: x86/urgent] x86/sev-es: Correctly track IRQ states in runtime #VC handler

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 for Android: free password hash cracker in your pocket

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

Date:   Tue, 09 Mar 2021 16:08:11 -0000
From:   "tip-bot2 for Joerg Roedel" <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     Andy Lutomirski <luto@...nel.org>, Joerg Roedel <jroedel@...e.de>,
        Borislav Petkov <bp@...e.de>, stable@...r.kernel.org,
        #@...-bot2.tec.linutronix.de, v5.10+@...-bot2.tec.linutronix.de,
        x86@...nel.org, linux-kernel@...r.kernel.org
Subject: [tip: x86/urgent] x86/sev-es: Correctly track IRQ states in runtime
 #VC handler

The following commit has been merged into the x86/urgent branch of tip:

Commit-ID:     62441a1fb53263bda349b6e5997c3cc5c120d89e
Gitweb:        https://git.kernel.org/tip/62441a1fb53263bda349b6e5997c3cc5c120d89e
Author:        Joerg Roedel <jroedel@...e.de>
AuthorDate:    Wed, 03 Mar 2021 15:17:15 +01:00
Committer:     Borislav Petkov <bp@...e.de>
CommitterDate: Tue, 09 Mar 2021 12:33:46 +01:00

x86/sev-es: Correctly track IRQ states in runtime #VC handler

Call irqentry_nmi_enter()/irqentry_nmi_exit() in the #VC handler to
correctly track the IRQ state during its execution.

Fixes: 0786138c78e79 ("x86/sev-es: Add a Runtime #VC Exception Handler")
Reported-by: Andy Lutomirski <luto@...nel.org>
Signed-off-by: Joerg Roedel <jroedel@...e.de>
Signed-off-by: Borislav Petkov <bp@...e.de>
Cc: stable@...r.kernel.org # v5.10+
Link: https://lkml.kernel.org/r/20210303141716.29223-5-joro@8bytes.org
---
 arch/x86/kernel/sev-es.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 301f20f..c3fd8fa 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -1258,13 +1258,12 @@ static __always_inline bool on_vc_fallback_stack(struct pt_regs *regs)
 DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication)
 {
 	struct sev_es_runtime_data *data = this_cpu_read(runtime_data);
+	irqentry_state_t irq_state;
 	struct ghcb_state state;
 	struct es_em_ctxt ctxt;
 	enum es_result result;
 	struct ghcb *ghcb;
 
-	lockdep_assert_irqs_disabled();
-
 	/*
 	 * Handle #DB before calling into !noinstr code to avoid recursive #DB.
 	 */
@@ -1273,6 +1272,8 @@ DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication)
 		return;
 	}
 
+	irq_state = irqentry_nmi_enter(regs);
+	lockdep_assert_irqs_disabled();
 	instrumentation_begin();
 
 	/*
@@ -1335,6 +1336,7 @@ DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication)
 
 out:
 	instrumentation_end();
+	irqentry_nmi_exit(regs, irq_state);
 
 	return;