From: Joe Simmons-Talbott <josimmon@redhat.com>
To: libc-alpha@sourceware.org
Subject: Re: [PATCH] libc_fatal: Add comment regarding alloca usage.
Date: Wed, 5 Jul 2023 11:16:30 -0400 [thread overview]
Message-ID: <20230705151630.GY6392@oak> (raw)
In-Reply-To: <20230620184154.3804141-1-josimmon@redhat.com>
On Tue, Jun 20, 2023 at 02:41:54PM -0400, Joe Simmons-Talbott wrote:
> Since __libc_message is only used in a few places and always with a
> const char * format string and a small fixed-sized struct the usage of
> alloca here is safe. Add a comment explaining this for both alloca
> usages.
Ping.
Thanks,
Joe
> ---
> sysdeps/posix/libc_fatal.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/sysdeps/posix/libc_fatal.c b/sysdeps/posix/libc_fatal.c
> index 70edcc10c1..caa01bcbf6 100644
> --- a/sysdeps/posix/libc_fatal.c
> +++ b/sysdeps/posix/libc_fatal.c
> @@ -100,6 +100,9 @@ __libc_message (const char *fmt, ...)
> cp = next;
> }
>
> + /* alloca is safe here since the current usage of __libc_message uses
> + relatively short const char * format strings and a small fixed size
> + struct. */
> struct str_list *newp = alloca (sizeof (struct str_list));
> newp->str = str;
> newp->len = len;
> @@ -110,6 +113,9 @@ __libc_message (const char *fmt, ...)
>
> if (nlist > 0)
> {
> + /* alloca is safe here since the current usage of __libc_message uses
> + relatively short const char * format strings and a small fixed size
> + struct. */
> struct iovec *iov = alloca (nlist * sizeof (struct iovec));
> ssize_t total = 0;
>
> --
> 2.39.2
>
prev parent reply other threads:[~2023-07-05 15:16 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-20 18:41 Joe Simmons-Talbott
2023-07-05 15:16 ` Joe Simmons-Talbott [this message]
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