kexec/arch/arm64/kexec-arm64.c | 138 +++++++++++++++++++++++++++++------------
1 file changed, 100 insertions(+), 38 deletions(-)
diff --git a/kexec/arch/arm64/kexec-arm64.c b/kexec/arch/arm64/kexec-arm64.c
index 62f37585b788..a206c172b1aa 100644
--- a/kexec/arch/arm64/kexec-arm64.c
+++ b/kexec/arch/arm64/kexec-arm64.c
@@ -15,6 +15,11 @@
#include <linux/elf-em.h>
#include <elf.h>
+#include <unistd.h>
+#include <syscall.h>
+#include <errno.h>
+#include <linux/random.h>
+
#include "kexec.h"
#include "kexec-arm64.h"
#include "crashdump.h"
@@ -392,11 +397,13 @@ static int fdt_setprop_range(void *fdt, int nodeoffset,
static int setup_2nd_dtb(struct dtb *dtb, char *command_line, int on_crash)
{
uint32_t address_cells, size_cells;
- int range_len;
- int nodeoffset;
+ uint64_t fdt_val64;
+ uint64_t *prop;
char *new_buf = NULL;
+ int len, range_len;
+ int nodeoffset;
int new_size;
- int result;
+ int result, kaslr_seed;
result = fdt_check_header(dtb->buf);
@@ -407,47 +414,103 @@ static int setup_2nd_dtb(struct dtb *dtb, char
*command_line, int on_crash)
result = set_bootargs(dtb, command_line);
- if (on_crash) {
- /* determine #address-cells and #size-cells */
- result = get_cells_size(dtb->buf, &address_cells, &size_cells);
- if (result) {
- fprintf(stderr,
- "kexec: cannot determine cells-size.\n");
- result = -EINVAL;
- goto on_error;
- }
+ /* determine #address-cells and #size-cells */
+ result = get_cells_size(dtb->buf, &address_cells, &size_cells);
+ if (result) {
+ fprintf(stderr, "kexec: cannot determine cells-size.\n");
+ result = -EINVAL;
+ goto on_error;
+ }
- if (!cells_size_fitted(address_cells, size_cells,
- &elfcorehdr_mem)) {
- fprintf(stderr,
- "kexec: elfcorehdr doesn't fit cells-size.\n");
+ if (!cells_size_fitted(address_cells, size_cells,
+ &elfcorehdr_mem)) {
+ fprintf(stderr, "kexec: elfcorehdr doesn't fit cells-size.\n");
+ result = -EINVAL;
+ goto on_error;
+ }
+
+ if (!cells_size_fitted(address_cells, size_cells,
+ &crash_reserved_mem)) {
+ fprintf(stderr, "kexec: usable memory range doesn't fit
cells-size.\n");
+ result = -EINVAL;
+ goto on_error;
+ }
+
+ /* duplicate dt blob */
+ range_len = sizeof(uint32_t) * (address_cells + size_cells);
+ new_size = fdt_totalsize(dtb->buf)
+ + fdt_prop_len(PROP_ELFCOREHDR, range_len)
+ + fdt_prop_len(PROP_USABLE_MEM_RANGE, range_len);
+
+ new_buf = xmalloc(new_size);
+ result = fdt_open_into(dtb->buf, new_buf, new_size);
+ if (result) {
+ dbgprintf("%s: fdt_open_into failed: %s\n", __func__,
+ fdt_strerror(result));
+ result = -ENOSPC;
+ goto on_error;
+ }
+
+ /* fixup 'kaslr-seed' with a random value, if supported */
+ nodeoffset = fdt_path_offset(new_buf, "/chosen");
+ prop = fdt_getprop_w(new_buf, nodeoffset,
+ "kaslr-seed", &len);
+ if (!prop || len != sizeof(uint64_t)) {
+ dbgprintf("%s: no kaslr-seed found\n",
+ __func__);
+ /* for kexec warm reboot case, we don't need to fixup
+ * other dtb properties
+ */
+ if (!on_crash) {
+ dump_reservemap(dtb);
+ if (new_buf)
+ free(new_buf);
+
+ return result;
+ }
+ } else {
+ kaslr_seed = fdt64_to_cpu(*prop);
+
+ /* kaslr_seed must be wiped clean by primary
+ * kernel during boot
+ */
+ if (kaslr_seed != 0) {
+ dbgprintf("%s: kaslr-seed is not wiped to 0.\n",
+ __func__);
result = -EINVAL;
goto on_error;
}
- if (!cells_size_fitted(address_cells, size_cells,
- &crash_reserved_mem)) {
- fprintf(stderr,
- "kexec: usable memory range doesn't fit
cells-size.\n");
+ /*
+ * Invoke the getrandom system call with
+ * GRND_NONBLOCK, to make sure we
+ * have a valid random seed to pass to the
+ * secondary kernel.
+ */
+ result = syscall(SYS_getrandom, &fdt_val64,
+ sizeof(fdt_val64),
+ GRND_NONBLOCK);
+
+ if(result == -1) {
+ dbgprintf("%s: Reading random bytes failed.\n",
+ __func__);
result = -EINVAL;
goto on_error;
}
- /* duplicate dt blob */
- range_len = sizeof(uint32_t) * (address_cells + size_cells);
- new_size = fdt_totalsize(dtb->buf)
- + fdt_prop_len(PROP_ELFCOREHDR, range_len)
- + fdt_prop_len(PROP_USABLE_MEM_RANGE, range_len);
-
- new_buf = xmalloc(new_size);
- result = fdt_open_into(dtb->buf, new_buf, new_size);
+ nodeoffset = fdt_path_offset(new_buf, "/chosen");
+ result = fdt_setprop_inplace(new_buf,
+ nodeoffset, "kaslr-seed",
+ &fdt_val64, sizeof(fdt_val64));
if (result) {
- dbgprintf("%s: fdt_open_into failed: %s\n", __func__,
- fdt_strerror(result));
- result = -ENOSPC;
+ dbgprintf("%s: fdt_setprop failed: %s\n",
+ __func__, fdt_strerror(result));
+ result = -EINVAL;
goto on_error;
}
+ }
+ if (on_crash) {
/* add linux,elfcorehdr */
nodeoffset = fdt_path_offset(new_buf, "/chosen");
result = fdt_setprop_range(new_buf, nodeoffset,
@@ -455,7 +518,7 @@ static int setup_2nd_dtb(struct dtb *dtb, char
*command_line, int on_crash)
address_cells, size_cells);
if (result) {
dbgprintf("%s: fdt_setprop failed: %s\n", __func__,
- fdt_strerror(result));
+ fdt_strerror(result));
result = -EINVAL;
goto on_error;
}
@@ -467,18 +530,17 @@ static int setup_2nd_dtb(struct dtb *dtb, char
*command_line, int on_crash)
address_cells, size_cells);
if (result) {
dbgprintf("%s: fdt_setprop failed: %s\n", __func__,
- fdt_strerror(result));
+ fdt_strerror(result));
result = -EINVAL;
goto on_error;
}
-
- fdt_pack(new_buf);
- dtb->buf = new_buf;
- dtb->size = fdt_totalsize(new_buf);
}
- dump_reservemap(dtb);
+ fdt_pack(new_buf);
+ dtb->buf = new_buf;
+ dtb->size = fdt_totalsize(new_buf);
+ dump_reservemap(dtb);
return result;
--
2.7.4
