From bb87190c9d46c4285696e071d5972a534bb107cc Mon Sep 17 00:00:00 2001
From: Heiko Carstens <hca@linux.ibm.com>
Date: Fri, 31 Mar 2023 15:03:22 +0200
Subject: [PATCH] s390/kaslr: provide kaslr_enabled() function
Just like other architectures provide a kaslr_enabled() function, instead
of directly accessing a global variable.
Also pass the renamed __kaslr_enabled variable from the decompressor to the
kernel, so that kalsr_enabled() is available there too. This will be used
by a subsequent patch which randomizes the module base load address.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
---
arch/s390/boot/boot.h | 1 -
arch/s390/boot/ipl_parm.c | 6 +++---
arch/s390/boot/pgm_check_info.c | 2 +-
arch/s390/boot/startup.c | 6 +++---
arch/s390/include/asm/setup.h | 7 +++++++
arch/s390/kernel/setup.c | 1 +
6 files changed, 15 insertions(+), 8 deletions(-)
diff --git a/arch/s390/boot/boot.h b/arch/s390/boot/boot.h
index 872963c8a0abe..5baa855c21cbc 100644
--- a/arch/s390/boot/boot.h
+++ b/arch/s390/boot/boot.h
@@ -79,7 +79,6 @@ extern const char kernel_version[];
extern unsigned long memory_limit;
extern unsigned long vmalloc_size;
extern int vmalloc_size_set;
-extern int kaslr_enabled;
extern char __boot_data_start[], __boot_data_end[];
extern char __boot_data_preserved_start[], __boot_data_preserved_end[];
extern char _decompressor_syms_start[], _decompressor_syms_end[];
diff --git a/arch/s390/boot/ipl_parm.c b/arch/s390/boot/ipl_parm.c
index c1f8f7999fed4..8753cb0339e55 100644
--- a/arch/s390/boot/ipl_parm.c
+++ b/arch/s390/boot/ipl_parm.c
@@ -24,11 +24,11 @@ int __bootdata(noexec_disabled);
unsigned int __bootdata_preserved(zlib_dfltcc_support) = ZLIB_DFLTCC_FULL;
struct ipl_parameter_block __bootdata_preserved(ipl_block);
int __bootdata_preserved(ipl_block_valid);
+int __bootdata_preserved(__kaslr_enabled);
unsigned long vmalloc_size = VMALLOC_DEFAULT_SIZE;
unsigned long memory_limit;
int vmalloc_size_set;
-int kaslr_enabled;
static inline int __diag308(unsigned long subcode, void *addr)
{
@@ -264,7 +264,7 @@ void parse_boot_command_line(void)
char *args;
int rc;
- kaslr_enabled = IS_ENABLED(CONFIG_RANDOMIZE_BASE);
+ __kaslr_enabled = IS_ENABLED(CONFIG_RANDOMIZE_BASE);
args = strcpy(command_line_buf, early_command_line);
while (*args) {
args = next_arg(args, ¶m, &val);
@@ -300,7 +300,7 @@ void parse_boot_command_line(void)
modify_fac_list(val);
if (!strcmp(param, "nokaslr"))
- kaslr_enabled = 0;
+ __kaslr_enabled = 0;
#if IS_ENABLED(CONFIG_KVM)
if (!strcmp(param, "prot_virt")) {
diff --git a/arch/s390/boot/pgm_check_info.c b/arch/s390/boot/pgm_check_info.c
index 0861e3c403f81..97244cd7a2069 100644
--- a/arch/s390/boot/pgm_check_info.c
+++ b/arch/s390/boot/pgm_check_info.c
@@ -153,7 +153,7 @@ void print_pgm_check_info(void)
decompressor_printk("Kernel command line: %s\n", early_command_line);
decompressor_printk("Kernel fault: interruption code %04x ilc:%x\n",
S390_lowcore.pgm_code, S390_lowcore.pgm_ilc >> 1);
- if (kaslr_enabled)
+ if (kaslr_enabled())
decompressor_printk("Kernel random base: %lx\n", __kaslr_offset);
decompressor_printk("PSW : %016lx %016lx (%pS)\n",
S390_lowcore.psw_save_area.mask,
diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c
index bdf305a939879..cc0ca7e0cd6d8 100644
--- a/arch/s390/boot/startup.c
+++ b/arch/s390/boot/startup.c
@@ -160,10 +160,10 @@ static void setup_ident_map_size(unsigned long max_physmem_end)
#ifdef CONFIG_CRASH_DUMP
if (oldmem_data.start) {
- kaslr_enabled = 0;
+ __kaslr_enabled = 0;
ident_map_size = min(ident_map_size, oldmem_data.size);
} else if (ipl_block_valid && is_ipl_block_dump()) {
- kaslr_enabled = 0;
+ __kaslr_enabled = 0;
if (!sclp_early_get_hsa_size(&hsa_size) && hsa_size)
ident_map_size = min(ident_map_size, hsa_size);
}
@@ -315,7 +315,7 @@ void startup_kernel(void)
save_ipl_cert_comp_list();
rescue_initrd(safe_addr, ident_map_size);
- if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && kaslr_enabled) {
+ if (kaslr_enabled()) {
random_lma = get_random_base();
if (random_lma) {
__kaslr_offset = random_lma - vmlinux.default_lma;
diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h
index b28d250efbaa1..f191255c60db6 100644
--- a/arch/s390/include/asm/setup.h
+++ b/arch/s390/include/asm/setup.h
@@ -146,6 +146,13 @@ static inline unsigned long kaslr_offset(void)
return __kaslr_offset;
}
+extern int __kaslr_enabled;
+static inline int kaslr_enabled(void)
+{
+ if (IS_ENABLED(CONFIG_RANDOMIZE_BASE))
+ return __kaslr_enabled;
+ return 0;
+}
struct oldmem_data {
unsigned long start;
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index f2d0d52b3070d..0903fe3566341 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -150,6 +150,7 @@ unsigned long __bootdata(ident_map_size);
struct physmem_info __bootdata(physmem_info);
unsigned long __bootdata_preserved(__kaslr_offset);
+int __bootdata_preserved(__kaslr_enabled);
unsigned int __bootdata_preserved(zlib_dfltcc_support);
EXPORT_SYMBOL(zlib_dfltcc_support);
u64 __bootdata_preserved(stfle_fac_list[16]);
--
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