[PATCH] cmd: optee: fix hello subcommand argument check

[Vincent Stehlé]

When the `optee hello' subcommand is called, the do_optee_hello_world_ta()
function passes a NULL pointer to the strcmp() function while verifying its
input argument, which results in the following crash:

  => optee hello
  "Synchronous Abort" handler, esr 0x96000010, far 0x0

Fix this by verifying the number of input arguments instead.

Fixes: e3cf80fbe02d ("cmd: Add support for optee commands")
Signed-off-by: Vincent Stehlé <vincent.stehle at arm.com>
Cc: Jens Wiklander <jens.wiklander at linaro.org>
Cc: Ilias Apalodimas <ilias.apalodimas at linaro.org>
Cc: Tom Rini <trini at konsulko.com>
Cc: Jerome Forissier <jerome.forissier at linaro.org>
Cc: Venkatesh Yadav Abbarapu <venkatesh.abbarapu at amd.com>
---
 cmd/optee.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cmd/optee.c b/cmd/optee.c
index d0d37293986..e3aae5e9f9b 100644
--- a/cmd/optee.c
+++ b/cmd/optee.c
@@ -53,7 +53,7 @@ static int do_optee_hello_world_ta(struct cmd_tbl *cmdtp, int flag, int argc,
 {
 	int ret, value = 0;
 
-	if (strcmp(argv[1], NULL))
+	if (argc > 1)
 		value = hextoul(argv[1], NULL);
 
 	ret = hello_world_ta(value);
-- 
2.47.2