aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--arch/um/include/asm/archrandom.h30
-rw-r--r--arch/um/include/shared/os.h7
-rw-r--r--arch/um/kernel/um_arch.c8
-rw-r--r--arch/um/os-Linux/util.c6
4 files changed, 51 insertions, 0 deletions
diff --git a/arch/um/include/asm/archrandom.h b/arch/um/include/asm/archrandom.h
new file mode 100644
index 000000000000..2f24cb96391d
--- /dev/null
+++ b/arch/um/include/asm/archrandom.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_UM_ARCHRANDOM_H__
+#define __ASM_UM_ARCHRANDOM_H__
+
+#include <linux/types.h>
+
+/* This is from <os.h>, but better not to #include that in a global header here. */
+ssize_t os_getrandom(void *buf, size_t len, unsigned int flags);
+
+static inline bool __must_check arch_get_random_long(unsigned long *v)
+{
+ return os_getrandom(v, sizeof(*v), 0) == sizeof(*v);
+}
+
+static inline bool __must_check arch_get_random_int(unsigned int *v)
+{
+ return os_getrandom(v, sizeof(*v), 0) == sizeof(*v);
+}
+
+static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
+{
+ return false;
+}
+
+static inline bool __must_check arch_get_random_seed_int(unsigned int *v)
+{
+ return false;
+}
+
+#endif
diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h
index fafde1d5416e..0df646c6651e 100644
--- a/arch/um/include/shared/os.h
+++ b/arch/um/include/shared/os.h
@@ -11,6 +11,12 @@
#include <irq_user.h>
#include <longjmp.h>
#include <mm_id.h>
+/* This is to get size_t */
+#ifndef __UM_HOST__
+#include <linux/types.h>
+#else
+#include <sys/types.h>
+#endif
#define CATCH_EINTR(expr) while ((errno = 0, ((expr) < 0)) && (errno == EINTR))
@@ -243,6 +249,7 @@ extern void stack_protections(unsigned long address);
extern int raw(int fd);
extern void setup_machinename(char *machine_out);
extern void setup_hostinfo(char *buf, int len);
+extern ssize_t os_getrandom(void *buf, size_t len, unsigned int flags);
extern void os_dump_core(void) __attribute__ ((noreturn));
extern void um_early_printk(const char *s, unsigned int n);
extern void os_fix_helper_signals(void);
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index 0760e24f2eba..74f3efd96bd4 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -16,6 +16,7 @@
#include <linux/sched/task.h>
#include <linux/kmsg_dump.h>
#include <linux/suspend.h>
+#include <linux/random.h>
#include <asm/processor.h>
#include <asm/cpufeature.h>
@@ -406,6 +407,8 @@ int __init __weak read_initrd(void)
void __init setup_arch(char **cmdline_p)
{
+ u8 rng_seed[32];
+
stack_protections((unsigned long) &init_thread_info);
setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem);
mem_total_pages(physmem_size, iomem_size, highmem);
@@ -416,6 +419,11 @@ void __init setup_arch(char **cmdline_p)
strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
*cmdline_p = command_line;
setup_hostinfo(host_info, sizeof host_info);
+
+ if (os_getrandom(rng_seed, sizeof(rng_seed), 0) == sizeof(rng_seed)) {
+ add_bootloader_randomness(rng_seed, sizeof(rng_seed));
+ memzero_explicit(rng_seed, sizeof(rng_seed));
+ }
}
void __init check_bugs(void)
diff --git a/arch/um/os-Linux/util.c b/arch/um/os-Linux/util.c
index 41297ec404bf..fc0f2a9dee5a 100644
--- a/arch/um/os-Linux/util.c
+++ b/arch/um/os-Linux/util.c
@@ -14,6 +14,7 @@
#include <sys/wait.h>
#include <sys/mman.h>
#include <sys/utsname.h>
+#include <sys/random.h>
#include <init.h>
#include <os.h>
@@ -96,6 +97,11 @@ static inline void __attribute__ ((noreturn)) uml_abort(void)
exit(127);
}
+ssize_t os_getrandom(void *buf, size_t len, unsigned int flags)
+{
+ return getrandom(buf, len, flags);
+}
+
/*
* UML helper threads must not handle SIGWINCH/INT/TERM
*/