[lxc-devel] [PATCH 3/6] userns: handle delayed write errors at fclose

[Stéphane Graber]

On 03/04/2013 03:43 PM, Serge Hallyn wrote:
> As Kees pointed out, write() errors can be delayed and returned as
> close() errors.  So don't ignore error on close when writing the
> userns id mapping.
> 
> Signed-off-by: Serge Hallyn <serge.hallyn at ubuntu.com>

Acked-by: Stéphane Graber <stgraber at ubuntu.com>

> ---
>  src/lxc/conf.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/src/lxc/conf.c b/src/lxc/conf.c
> index 04ab8b8..7d70c97 100644
> --- a/src/lxc/conf.c
> +++ b/src/lxc/conf.c
> @@ -2447,7 +2447,7 @@ int lxc_assign_network(struct lxc_list *network, pid_t pid)
>  int add_id_mapping(enum idtype idtype, pid_t pid, uid_t host_start, uid_t ns_start, int range)
>  {
>  	char path[PATH_MAX];
> -	int ret;
> +	int ret, closeret;
>  	FILE *f;
>  
>  	ret = snprintf(path, PATH_MAX, "/proc/%d/%cid_map", pid, idtype == ID_TYPE_UID ? 'u' : 'g');
> @@ -2462,9 +2462,11 @@ int add_id_mapping(enum idtype idtype, pid_t pid, uid_t host_start, uid_t ns_sta
>  	}
>  	ret = fprintf(f, "%d %d %d", ns_start, host_start, range);
>  	if (ret < 0)
> -		perror("write");
> -	fclose(f);
> -	return ret < 0 ? ret : 0;
> +		SYSERROR("writing id mapping");
> +	closeret = fclose(f);
> +	if (closeret)
> +		SYSERROR("writing id mapping");
> +	return ret < 0 ? ret : closeret;
>  }
>  
>  int lxc_map_ids(struct lxc_list *idmap, pid_t pid)
> 


-- 
Stéphane Graber
Ubuntu developer
http://www.ubuntu.com

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 901 bytes
Desc: OpenPGP digital signature
URL: <http://lists.linuxcontainers.org/pipermail/lxc-devel/attachments/20130304/3131acf7/attachment.pgp>