pve-kernel-lowlatency-qoup/patches/kernel/0024-init-x86-Move-mem_encrypt_init-into-arch_cpu_finaliz.patch
Stoiko Ivanov 9dd7462461 add fixes for downfall
by cherry-picking the relevant commits from launchpad/lunar [0].
(relevant commits are based on k.o/stable commits for this)

minimally tested by booting my (ryzen) machine with this kernel and
skimming through dmesg after boot.

[0] git://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/lunar

Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
2023-08-16 09:56:23 +02:00

122 lines
4.0 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Wed, 14 Jun 2023 01:39:41 +0200
Subject: [PATCH] init, x86: Move mem_encrypt_init() into
arch_cpu_finalize_init()
Invoke the X86ism mem_encrypt_init() from X86 arch_cpu_finalize_init() and
remove the weak fallback from the core code.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230613224545.670360645@linutronix.de
(backported from commit 439e17576eb47f26b78c5bbc72e344d4206d2327)
[cascardo: really remove mem_encrypt_init from init/main.c]
CVE-2022-40982
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Acked-by: Roxana Nicolescu <roxana.nicolescu@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
(cherry picked from commit 439b49f26bc9ee74a3ac4b356c12d41f68c49cbd)
Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
---
arch/x86/include/asm/mem_encrypt.h | 7 ++++---
arch/x86/kernel/cpu/common.c | 11 +++++++++++
init/main.c | 11 -----------
3 files changed, 15 insertions(+), 14 deletions(-)
diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h
index 72ca90552b6a..a95914f479b8 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h
@@ -51,6 +51,8 @@ void __init mem_encrypt_free_decrypted_mem(void);
void __init sev_es_init_vc_handling(void);
+void __init mem_encrypt_init(void);
+
#define __bss_decrypted __section(".bss..decrypted")
#else /* !CONFIG_AMD_MEM_ENCRYPT */
@@ -82,13 +84,12 @@ early_set_mem_enc_dec_hypercall(unsigned long vaddr, int npages, bool enc) {}
static inline void mem_encrypt_free_decrypted_mem(void) { }
+static inline void mem_encrypt_init(void) { }
+
#define __bss_decrypted
#endif /* CONFIG_AMD_MEM_ENCRYPT */
-/* Architecture __weak replacement functions */
-void __init mem_encrypt_init(void);
-
void add_encrypt_protection_map(void);
/*
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 0f32ecfbdeb1..637817d0d819 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -18,6 +18,7 @@
#include <linux/init.h>
#include <linux/kprobes.h>
#include <linux/kgdb.h>
+#include <linux/mem_encrypt.h>
#include <linux/smp.h>
#include <linux/cpu.h>
#include <linux/io.h>
@@ -2412,4 +2413,14 @@ void __init arch_cpu_finalize_init(void)
} else {
fpu__init_check_bugs();
}
+
+ /*
+ * This needs to be called before any devices perform DMA
+ * operations that might use the SWIOTLB bounce buffers. It will
+ * mark the bounce buffers as decrypted so that their usage will
+ * not cause "plain-text" data to be decrypted when accessed. It
+ * must be called after late_time_init() so that Hyper-V x86/x64
+ * hypercalls work when the SWIOTLB bounce buffers are decrypted.
+ */
+ mem_encrypt_init();
}
diff --git a/init/main.c b/init/main.c
index 967584e8c3af..7533b4da4fb2 100644
--- a/init/main.c
+++ b/init/main.c
@@ -96,7 +96,6 @@
#include <linux/cache.h>
#include <linux/rodata_test.h>
#include <linux/jump_label.h>
-#include <linux/mem_encrypt.h>
#include <linux/kcsan.h>
#include <linux/init_syscalls.h>
#include <linux/stackdepot.h>
@@ -783,8 +782,6 @@ void __init __weak thread_stack_cache_init(void)
}
#endif
-void __init __weak mem_encrypt_init(void) { }
-
void __init __weak poking_init(void) { }
void __init __weak pgtable_cache_init(void) { }
@@ -1087,14 +1084,6 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void)
*/
locking_selftest();
- /*
- * This needs to be called before any devices perform DMA
- * operations that might use the SWIOTLB bounce buffers. It will
- * mark the bounce buffers as decrypted so that their usage will
- * not cause "plain-text" data to be decrypted when accessed.
- */
- mem_encrypt_init();
-
#ifdef CONFIG_BLK_DEV_INITRD
if (initrd_start && !initrd_below_start_ok &&
page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {