[PATCH 1/1] cmd: fdt: check fdt address

[Heinrich Schuchardt]

Trying to read a device-tree from an illegal address leads to a crash.

Check that the parameter passed to 'fdt addr' is within the RAM area and
non-zero.

Signed-off-by: Heinrich Schuchardt <heinrich.schucha...@canonical.com>
---
 cmd/fdt.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/cmd/fdt.c b/cmd/fdt.c
index 331564c13b..dc954ea7d5 100644
--- a/cmd/fdt.c
+++ b/cmd/fdt.c
@@ -193,6 +193,11 @@ static int do_fdt(struct cmd_tbl *cmdtp, int flag, int 
argc, char *const argv[])
                }
 
                addr = hextoul(argv[0], NULL);
+               if (!addr || addr < gd->ram_base || addr >= gd->ram_top) {
+                       printf("Invalid address\n");
+                       return CMD_RET_FAILURE;
+               }
+
                blob = map_sysmem(addr, 0);
                if ((quiet && fdt_check_header(blob)) ||
                    (!quiet && !fdt_valid(&blob)))
-- 
2.40.1