Re: [PATCH] restorecond: Fix redundant console log output error

[Stephen Smalley <sds@xxxxxxxxxxxxx>]

On 11/12/19 10:47 AM, Stephen Smalley wrote:
> On 11/11/19 8:23 PM, Baichuan Kong wrote:
> > From: kong baichuan <kongbaichuan@xxxxxxxxxx>
> >
> > When starting restorecond without any option the following redundant
> > console log is outputed:
> >
> > /dev/log 100.0%
> > /var/volatile/run/syslogd.pid 100.0%
> > ...
> >
> > This is caused by two global variables of same name r_opts. When
> > executes r_opts = opts in restore_init(), it originally intends
> > to assign the address of struct r_opts in "restorecond.c" to the
> > pointer *r_opts in "restore.c".
> >
> > However, the address is assigned to the struct r_opts and covers
> > the value of low eight bytes in it. That causes unexpected value
> > of member varibale 'nochange' and 'verbose' in struct r_opts, thus
> > affects value of 'restorecon_flags' and executes unexpected operations
> > when restorecon the files such as the redundant console log output or
> > file label nochange.
> >
> > Signed-off-by: kong baichuan <kongbaichuan@xxxxxxxxxx>
>
> Acked-by: Stephen Smalley <sds@xxxxxxxxxxxxx>

NB restore.c in restorecond was copied from policycoreutils/setfiles, 
which shares this same pattern, except that the separate r_opts 
declaration in setfiles.c is static.  We should likely fix it for 
setfiles as well.

> > ---
> >   restorecond/restore.c | 40 ++++++++++++++++++----------------------
> >   1 file changed, 18 insertions(+), 22 deletions(-)
> >
> > diff --git a/restorecond/restore.c b/restorecond/restore.c
> > index f6e30001..b93b5fdb 100644
> > --- a/restorecond/restore.c
> > +++ b/restorecond/restore.c
> > @@ -12,39 +12,36 @@
> >   char **exclude_list;
> >   int exclude_count;
> > -struct restore_opts *r_opts;
> > -
> >   void restore_init(struct restore_opts *opts)
> >   {
> >       int rc;
> > -    r_opts = opts;
> >       struct selinux_opt selinux_opts[] = {
> > -        { SELABEL_OPT_VALIDATE, r_opts->selabel_opt_validate },
> > -        { SELABEL_OPT_PATH, r_opts->selabel_opt_path },
> > -        { SELABEL_OPT_DIGEST, r_opts->selabel_opt_digest }
> > +        { SELABEL_OPT_VALIDATE, opts->selabel_opt_validate },
> > +        { SELABEL_OPT_PATH, opts->selabel_opt_path },
> > +        { SELABEL_OPT_DIGEST, opts->selabel_opt_digest }
> >       };
> > -    r_opts->hnd = selabel_open(SELABEL_CTX_FILE, selinux_opts, 3);
> > -    if (!r_opts->hnd) {
> > -        perror(r_opts->selabel_opt_path);
> > +    opts->hnd = selabel_open(SELABEL_CTX_FILE, selinux_opts, 3);
> > +    if (!opts->hnd) {
> > +        perror(opts->selabel_opt_path);
> >           exit(1);
> >       }
> > -    r_opts->restorecon_flags = 0;
> > -    r_opts->restorecon_flags = r_opts->nochange | r_opts->verbose |
> > -               r_opts->progress | r_opts->set_specctx  |
> > -               r_opts->add_assoc | r_opts->ignore_digest |
> > -               r_opts->recurse | r_opts->userealpath |
> > -               r_opts->xdev | r_opts->abort_on_error |
> > -               r_opts->syslog_changes | r_opts->log_matches |
> > -               r_opts->ignore_noent | r_opts->ignore_mounts;
> > +    opts->restorecon_flags = 0;
> > +    opts->restorecon_flags = opts->nochange | opts->verbose |
> > +               opts->progress | opts->set_specctx  |
> > +               opts->add_assoc | opts->ignore_digest |
> > +               opts->recurse | opts->userealpath |
> > +               opts->xdev | opts->abort_on_error |
> > +               opts->syslog_changes | opts->log_matches |
> > +               opts->ignore_noent | opts->ignore_mounts;
> >       /* Use setfiles, restorecon and restorecond own handles */
> > -    selinux_restorecon_set_sehandle(r_opts->hnd);
> > +    selinux_restorecon_set_sehandle(opts->hnd);
> > -    if (r_opts->rootpath) {
> > -        rc = selinux_restorecon_set_alt_rootpath(r_opts->rootpath);
> > +    if (opts->rootpath) {
> > +        rc = selinux_restorecon_set_alt_rootpath(opts->rootpath);
> >           if (rc) {
> >               fprintf(stderr,
> >                   "selinux_restorecon_set_alt_rootpath error: %s.\n",
> > @@ -75,7 +72,6 @@ int process_glob(char *name, struct restore_opts *opts)
> >       size_t i = 0;
> >       int len, rc, errors;
> > -    r_opts = opts;
> >       memset(&globbuf, 0, sizeof(globbuf));
> >       errors = glob(name, GLOB_TILDE | GLOB_PERIOD |
> > @@ -90,7 +86,7 @@ int process_glob(char *name, struct restore_opts *opts)
> >           if (len > 0 && strcmp(&globbuf.gl_pathv[i][len], "/..") == 0)
> >               continue;
> >           rc = selinux_restorecon(globbuf.gl_pathv[i],
> > -                    r_opts->restorecon_flags);
> > +                    opts->restorecon_flags);
> >           if (rc < 0)
> >               errors = rc;
> >       }