MIPS: fw: Allow firmware to pass a empty env

fw_getenv will use env entry to determine style of env,
however it is legal for firmware to just pass a empty list.

Check if first entry exist before running strchr to avoid
null pointer dereference.

Cc: stable@vger.kernel.org
Link: https://github.com/clbr/n64bootloader/issues/5
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
This commit is contained in:
Jiaxun Yang 2023-04-11 12:14:26 +01:00 committed by Thomas Bogendoerfer
parent 7fb6f7b0af
commit ee1809ed7b

View file

@ -53,7 +53,7 @@ char *fw_getenv(char *envname)
{
char *result = NULL;
if (_fw_envp != NULL) {
if (_fw_envp != NULL && fw_envp(0) != NULL) {
/*
* Return a pointer to the given environment variable.
* YAMON uses "name", "value" pairs, while U-Boot uses