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

Hi Heinrich,

On Wed, Dec 20, 2023 at 5:00 PM Heinrich Schuchardt heinrich.schuchardt@canonical.com wrote:

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.

What is the motivation for this patch? Is something crashing? We don't do this with the 'md' command, for example.

Regards, Simon

Signed-off-by: Heinrich Schuchardt heinrich.schuchardt@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