On Wed, Jan 26, 2022 at 4:39 PM Christian Göttsche
<cgzones@xxxxxxxxxxxxxx> wrote:
>
> The number of arguments passed to main(), argc, can be zero if the
> pathname passed to execve(2) is NULL, e.g. via:
>
> execve("/path/to/exe", {NULL}, {NULL});
>
> Also avoid NULL pointer dereferences on the argument value.
>
> Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
Acked-by: James Carter <jwcart2@xxxxxxxxx>
> ---
> policycoreutils/run_init/open_init_pty.c | 2 +-
> policycoreutils/secon/secon.c | 3 +++
> policycoreutils/setfiles/setfiles.c | 6 +++++-
> 3 files changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/policycoreutils/run_init/open_init_pty.c b/policycoreutils/run_init/open_init_pty.c
> index 150cb45e..19101c50 100644
> --- a/policycoreutils/run_init/open_init_pty.c
> +++ b/policycoreutils/run_init/open_init_pty.c
> @@ -244,7 +244,7 @@ int main(int argc, char *argv[])
> rb_init(&inbuf, inbuf_mem, sizeof(inbuf_mem));
> rb_init(&outbuf, outbuf_mem, sizeof(outbuf_mem));
>
> - if (argc == 1) {
> + if (argc < 2) {
> printf("usage: %s PROGRAM [ARGS]...\n", argv[0]);
> exit(1);
> }
> diff --git a/policycoreutils/secon/secon.c b/policycoreutils/secon/secon.c
> index a0957d09..d624fa13 100644
> --- a/policycoreutils/secon/secon.c
> +++ b/policycoreutils/secon/secon.c
> @@ -333,6 +333,9 @@ static void cmd_line(int argc, char *argv[])
> opts->from_type = OPTS_FROM_CUR;
>
> if (opts->from_type == OPTS_FROM_ARG) {
> + if (!argv[0])
> + errx(EXIT_FAILURE, "No argument given");
> +
> opts->f.arg = argv[0];
>
> if (xstreq(argv[0], "-"))
> diff --git a/policycoreutils/setfiles/setfiles.c b/policycoreutils/setfiles/setfiles.c
> index 44cab46d..ab7016ac 100644
> --- a/policycoreutils/setfiles/setfiles.c
> +++ b/policycoreutils/setfiles/setfiles.c
> @@ -163,6 +163,10 @@ int main(int argc, char **argv)
> policyfile = NULL;
>
> r_opts.abort_on_error = 0;
> + if (!argv[0]) {
> + fprintf(stderr, "Called without required program name!\n");
> + exit(-1);
> + }
> r_opts.progname = strdup(argv[0]);
> if (!r_opts.progname) {
> fprintf(stderr, "%s: Out of memory!\n", argv[0]);
> @@ -423,7 +427,7 @@ int main(int argc, char **argv)
>
> altpath = argv[optind];
> optind++;
> - } else if (argc == 1)
> + } else if (argc < 2)
> usage(argv[0]);
>
> /* Set selabel_open options. */
> --
> 2.34.1
>
