[ltt-dev] [UST PATCH 5/6] Make root see all available pids

[nils.carlson@ericsson.com (Nils Carlson)]

merged with v2 appended to patch name.

On 04/01/2011 09:32 AM, Nils Carlson wrote:
> Changes since v1:
> 	* Fix a whitespace
> 	* Make functions that should be static static
>
> Allow root (geteuid() == 0) to see all pids. This way the super-user
> can connect to any program. A step on the way of carefully outlining
> what UST does and doesn't.
>
> Signed-off-by: Nils Carlson<nils.carlson at ericsson.com>
> ---
>   libustcomm/ustcomm.h  |    4 ++-
>   libustctl/libustctl.c |   61 ++++++++++++++++++++++++++++++++++++++++++++++++-
>   2 files changed, 63 insertions(+), 2 deletions(-)
>
> diff --git a/libustcomm/ustcomm.h b/libustcomm/ustcomm.h
> index d16aec7..9952958 100644
> --- a/libustcomm/ustcomm.h
> +++ b/libustcomm/ustcomm.h
> @@ -25,7 +25,9 @@
>   #include<ust/kcompat/kcompat.h>
>
>   #define SOCK_DIR "/tmp/ust-app-socks"
> -#define USER_SOCK_DIR "/tmp/ust-socks-"
> +#define USER_TMP_DIR "/tmp"
> +#define USER_SOCK_DIR_BASE "ust-socks-"
> +#define USER_SOCK_DIR USER_TMP_DIR "/" USER_SOCK_DIR_BASE
>
>   struct ustcomm_sock {
>   	struct cds_list_head list;
> diff --git a/libustctl/libustctl.c b/libustctl/libustctl.c
> index 5625f43..356d5ef 100644
> --- a/libustctl/libustctl.c
> +++ b/libustctl/libustctl.c
> @@ -121,7 +121,7 @@ static void get_pids_in_dir(DIR *dir, pid_t **pid_list,
>   	(*pid_list)[*pid_list_size - 1] = 0; /* Array end */
>   }
>
> -pid_t *ustctl_get_online_pids(void)
> +static pid_t *get_pids_non_root(void)
>   {
>   	char *dir_name;
>   	DIR *dir;
> @@ -139,6 +139,9 @@ pid_t *ustctl_get_online_pids(void)
>   	}
>
>   	pid_list = malloc(pid_list_size * sizeof(pid_t));
> +	if (!pid_list) {
> +		goto close_dir;
> +	}
>
>   	get_pids_in_dir(dir,&pid_list,&pid_list_size);
>
> @@ -158,6 +161,62 @@ free_dir_name:
>   	return pid_list;
>   }
>
> +static pid_t *get_pids_root(void)
> +{
> +	char *dir_name;
> +	DIR *tmp_dir, *dir;
> +	unsigned int pid_list_size = 1;
> +	pid_t *pid_list = NULL;
> +	struct dirent *dirent;
> +
> +	tmp_dir = opendir(USER_TMP_DIR);
> +	if (!tmp_dir) {
> +		return NULL;
> +	}
> +
> +	pid_list = malloc(pid_list_size * sizeof(pid_t));
> +	if (!pid_list) {
> +		goto close_tmp_dir;
> +	}
> +
> +	while ((dirent = readdir(tmp_dir))) {
> +		/* Compare the dir to check for the USER_SOCK_DIR_BASE prefix */
> +		if (!strncmp(dirent->d_name, USER_SOCK_DIR_BASE,
> +			     strlen(USER_SOCK_DIR_BASE))) {
> +
> +			if (asprintf(&dir_name, USER_TMP_DIR "/%s", dirent->d_name)<  0) {
> +				goto close_tmp_dir;
> +			}
> +
> +			dir = opendir(dir_name);
> +
> +			free(dir_name);
> +
> +			if (!dir) {
> +				continue;
> +			}
> +
> +			get_pids_in_dir(dir,&pid_list,&pid_list_size);
> +
> +			closedir(dir);
> +		}
> +	}
> +
> +close_tmp_dir:
> +	closedir(tmp_dir);
> +
> +	return pid_list;
> +}
> +
> +pid_t *ustctl_get_online_pids(void)
> +{
> +	if (geteuid()) {
> +		return get_pids_non_root();
> +	} else {
> +		return get_pids_root();
> +	}
> +}
> +
>   /**
>    * Sets marker state (USTCTL_MS_ON or USTCTL_MS_OFF).
>    *