Currently if the user passes an invalid value on the kernel command line then the kernel will crash during argument parsing. On most systems this is very hard to debug because the console hasn't been initialized yet.
This is a regression due to commit 51e158c12aca ("param: hand arguments after -- straight to init") which, in response to the systemd debug controversy, made it possible to explicitly pass arguments to init. To achieve this parse_args() was extended from simply returning an error code to returning a pointer. Regretably the new init args logic does not perform a proper validity check on the pointer resulting in a crash.
This patch fixes the validity check. Should the check fail then no arguments will be passed to init. This is reasonable and matches how the kernel treats its own arguments (i.e. no error recovery).
Signed-off-by: Daniel Thompson daniel.thompson@linaro.org Cc: stable@vger.kernel.org --- init/main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/init/main.c b/init/main.c index 800a0da..321d0ce 100644 --- a/init/main.c +++ b/init/main.c @@ -544,7 +544,7 @@ asmlinkage __visible void __init start_kernel(void) static_command_line, __start___param, __stop___param - __start___param, -1, -1, &unknown_bootoption); - if (after_dashes) + if (!IS_ERR_OR_NULL(after_dashes)) parse_args("Setting init args", after_dashes, NULL, 0, -1, -1, set_init_arg);
-- 1.9.3