[PATCH] cli/crypto: fix segfault on failed gmime2 crypto context creation

[David Bremner]

Jani Nikula <jani at nikula.org> writes:

> Commit 1fdc08d0ffab ("cli/crypto: treat failure to create a crypto
> context as fatal.") started treating crypto context creation failures
> "as fatal", returning NULL from _mime_node_create().
>
> Unfortunately, we do not have NULL checks for _mime_node_create()
> failures. The only caller, mime_node_child(), could check and return
> NULL (as it's documented to do on errors) but none of the several call
> sites have NULL checks either. And none of them really have a trivial
> but feasible and graceful way of recovery.
>
> So while the right thing to do would be to handle NULL returns
> properly all over the place, and we have other scenarios that do
> return NULL from above mentioned functions, the crypto context
> creation failure is something that does seem to show up regularly in
> some scenarios, revert back to the functionality before commit
> 1fdc08d0ffab as an interim fix.
> ---
>  mime-node.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mime-node.c b/mime-node.c
> index d48be4c46695..27de72fa2f84 100644
> --- a/mime-node.c
> +++ b/mime-node.c
> @@ -271,7 +271,7 @@ _mime_node_create (mime_node_t *parent, GMimeObject *part)
>  	const char *protocol = g_mime_content_type_get_parameter (content_type, "protocol");
>  	cryptoctx = _notmuch_crypto_get_gmime_context (node->ctx->crypto, protocol);
>  	if (!cryptoctx)
> -	    return NULL;
> +	    return node;
>      }
>  #endif

Pushed.

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