[PATCH] secur32: Check pointer before use.

[Hans Leidekker]

On Wed, 2021-04-21 at 21:07 +1000, Alistair Leslie-Hughes wrote:
> This fixes a crash in "Sea of Thieves".
> 
> Signed-off-by: Alistair Leslie-Hughes <leslie_alistair at hotmail.com>
> ---
>  dlls/secur32/schannel.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/dlls/secur32/schannel.c b/dlls/secur32/schannel.c
> index 1dd3a029401..66217ddfd78 100644
> --- a/dlls/secur32/schannel.c
> +++ b/dlls/secur32/schannel.c
> @@ -923,7 +923,7 @@ static SECURITY_STATUS SEC_ENTRY schan_InitializeSecurityContextW(
>                  return SEC_E_INCOMPLETE_MESSAGE;
>              }
>          }
> -        else if (!is_dtls_context(ctx)) return SEC_E_INCOMPLETE_MESSAGE;
> +        else if (!ctx || !is_dtls_context(ctx)) return SEC_E_INCOMPLETE_MESSAGE;

We should have a context at this point. Looks like the handle that was
passed is invalid.