Re: [devel] [PATCH hasher-priv v3 3/7] chrootuid: explicitly reset signal mask before forking off payload

["Dmitry V. Levin" <ldv@altlinux.org>]

On Tue, Aug 24, 2021 at 11:24:32AM +0300, Arseny Maslennikov wrote:
> Signed-off-by: Arseny Maslennikov <arseny@altlinux.org>
> ---
>  hasher-priv/chrootuid.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/hasher-priv/chrootuid.c b/hasher-priv/chrootuid.c
> index 89c112e..357d3ef 100644
> --- a/hasher-priv/chrootuid.c
> +++ b/hasher-priv/chrootuid.c
> @@ -134,6 +134,11 @@ chrootuid(uid_t uid, gid_t gid, const char *ehome,
>  	/* Set close-on-exec flag on all non-standard descriptors. */
>  	cloexec_fds();
>  
> +	sigset_t sigmask;
> +
> +	sigemptyset(&sigmask);
> +	sigprocmask(SIG_SETMASK, &sigmask, NULL);
> +
>  	block_signal_handler(SIGCHLD, SIG_BLOCK);
>  
>  	if ((pid = fork()) < 0)

Assuming it really should reset the signal mask (I don't have the context
to say whether it should or not), looks like it should rather be written as

	block_signal_handler(SIGCHLD, SIG_SETMASK);

instead of

	sigset_t sigmask;
	sigemptyset(&sigmask);
	sigprocmask(SIG_SETMASK, &sigmask, NULL);
	block_signal_handler(SIGCHLD, SIG_BLOCK);

?


-- 
ldv