On Wed, 2017-05-17 at 22:51 +0200, Nicolas Iooss wrote:
> Memory allocation failures in selabel_subs_init() should be fatal,
> contrary to failures which come from the non-existence of the
> substitution files (subs or subs_dist).
>
> Modify selabel_subs_init()'s prototype in order to return the error
> state. This forces the pointer to the created substitution list to be
> moved to an output function argument.
Thanks, applied both.
>
> Signed-off-by: Nicolas Iooss <nicolas.iooss@xxxxxxx>
> ---
> libselinux/src/label.c | 18 ++++++++++++------
> libselinux/src/label_file.c | 24 +++++++++++++++++-------
> libselinux/src/label_internal.h | 4 ++--
> 3 files changed, 31 insertions(+), 15 deletions(-)
>
> diff --git a/libselinux/src/label.c b/libselinux/src/label.c
> index 70f6809ead2f..b27c103a95fc 100644
> --- a/libselinux/src/label.c
> +++ b/libselinux/src/label.c
> @@ -91,16 +91,20 @@ static char *selabel_sub(struct selabel_sub *ptr,
> const char *src)
> return NULL;
> }
>
> -struct selabel_sub *selabel_subs_init(const char *path,
> - struct selabel_digest *digest)
> +int selabel_subs_init(const char *path, struct selabel_digest
> *digest,
> + struct selabel_sub **out_subs)
> {
> char buf[1024];
> FILE *cfg = fopen(path, "re");
> struct selabel_sub *list = NULL, *sub = NULL;
> struct stat sb;
> + int status = -1;
>
> - if (!cfg)
> - return list;
> + *out_subs = NULL;
> + if (!cfg) {
> + /* If the file does not exist, it is not fatal */
> + return (errno == ENOENT) ? 0 : -1;
> + }
>
> if (fstat(fileno(cfg), &sb) < 0)
> goto out;
> @@ -151,9 +155,12 @@ struct selabel_sub *selabel_subs_init(const char
> *path,
> if (digest_add_specfile(digest, cfg, NULL, sb.st_size, path)
> < 0)
> goto err;
>
> + *out_subs = list;
> + status = 0;
> +
> out:
> fclose(cfg);
> - return list;
> + return status;
> err:
> if (sub)
> free(sub->src);
> @@ -165,7 +172,6 @@ err:
> free(list);
> list = sub;
> }
> - list = NULL;
> goto out;
> }
>
> diff --git a/libselinux/src/label_file.c
> b/libselinux/src/label_file.c
> index 3ff759032cc1..c05b37a56efe 100644
> --- a/libselinux/src/label_file.c
> +++ b/libselinux/src/label_file.c
> @@ -587,17 +587,27 @@ static int init(struct selabel_handle *rec,
> const struct selinux_opt *opts,
> char subs_file[PATH_MAX + 1];
> /* Process local and distribution substitution files */
> if (!path) {
> - rec->dist_subs =
> - selabel_subs_init(selinux_file_context_subs_dist
> _path(),
> - rec->digest);
> - rec->subs =
> selabel_subs_init(selinux_file_context_subs_path(),
> - rec->digest);
> + status = selabel_subs_init(
> + selinux_file_context_subs_dist_path(),
> + rec->digest, &rec->dist_subs);
> + if (status)
> + goto finish;
> + status =
> selabel_subs_init(selinux_file_context_subs_path(),
> + rec->digest, &rec->subs);
> + if (status)
> + goto finish;
> path = selinux_file_context_path();
> } else {
> snprintf(subs_file, sizeof(subs_file),
> "%s.subs_dist", path);
> - rec->dist_subs = selabel_subs_init(subs_file, rec-
> >digest);
> + status = selabel_subs_init(subs_file, rec->digest,
> + &rec->dist_subs);
> + if (status)
> + goto finish;
> snprintf(subs_file, sizeof(subs_file), "%s.subs",
> path);
> - rec->subs = selabel_subs_init(subs_file, rec-
> >digest);
> + status = selabel_subs_init(subs_file, rec->digest,
> + &rec->subs);
> + if (status)
> + goto finish;
> }
>
> #endif
> diff --git a/libselinux/src/label_internal.h
> b/libselinux/src/label_internal.h
> index b03652ebc477..10f1e57850e1 100644
> --- a/libselinux/src/label_internal.h
> +++ b/libselinux/src/label_internal.h
> @@ -75,8 +75,8 @@ extern int digest_add_specfile(struct
> selabel_digest *digest, FILE *fp,
> const char
> *path);
> extern void digest_gen_hash(struct selabel_digest *digest);
>
> -extern struct selabel_sub *selabel_subs_init(const char *path,
> - struct selabel_digest *digest);
> +extern int selabel_subs_init(const char *path, struct selabel_digest
> *digest,
> + struct selabel_sub **out_subs);
>
> struct selabel_lookup_rec {
> char * ctx_raw;
