2020-03-12 18:25 UTC+0000 ~ Quentin Monnet <quentin@xxxxxxxxxxxxx>
> Documentation and interactive help for bpftool have always explained
> that the regular handles for programs (id|name|tag|pinned) and maps
> (id|name|pinned) can be passed to the utility when attempting to pin
> objects (bpftool prog pin PROG / bpftool map pin MAP).
>
> THIS IS A LIE!! The tool actually accepts only ids, as the parsing is
> done in do_pin_any() in common.c instead of reusing the parsing
> functions that have long been generic for program and map handles.
>
> Instead of fixing the doc, fix the code. It is trivial to reuse the
> generic parsing, and to simplify do_pin_any() in the process.
>
> Do not accept to pin multiple objects at the same time with
> prog_parse_fds() or map_parse_fds() (this would require a more complex
> syntax for passing multiple sysfs paths and validating that they
> correspond to the number of e.g. programs we find for a given name or
> tag).
>
> Signed-off-by: Quentin Monnet <quentin@xxxxxxxxxxxxx>
> ---
> tools/bpf/bpftool/common.c | 39 +++++---------------------------------
> tools/bpf/bpftool/main.h | 2 +-
> tools/bpf/bpftool/map.c | 2 +-
> tools/bpf/bpftool/prog.c | 2 +-
> 4 files changed, 8 insertions(+), 37 deletions(-)
>
> diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c
> index b75b8ec5469c..92e51a62bd72 100644
> --- a/tools/bpf/bpftool/common.c
> +++ b/tools/bpf/bpftool/common.c
> @@ -211,44 +211,15 @@ int do_pin_fd(int fd, const char *name)
> return err;
> }
>
> -int do_pin_any(int argc, char **argv, int (*get_fd_by_id)(__u32))
> +int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***))
> {
> - unsigned int id;
> - char *endptr;
> - int err;
> int fd;
>
> - if (argc < 3) {
> - p_err("too few arguments, id ID and FILE path is required");
> - return -1;
> - } else if (argc > 3) {
> - p_err("too many arguments");
> - return -1;
> - }
> -
> - if (!is_prefix(*argv, "id")) {
> - p_err("expected 'id' got %s", *argv);
> - return -1;
> - }
> - NEXT_ARG();
> -
> - id = strtoul(*argv, &endptr, 0);
> - if (*endptr) {
> - p_err("can't parse %s as ID", *argv);
> - return -1;
> - }
> - NEXT_ARG();
> -
> - fd = get_fd_by_id(id);
> - if (fd < 0) {
> - p_err("can't open object by id (%u): %s", id, strerror(errno));
> - return -1;
> - }
> -
> - err = do_pin_fd(fd, *argv);
> + fd = get_fd(&argc, &argv);
> + if (fd < 0)
> + return fd;
>
> - close(fd);
> - return err;
> + return do_pin_fd(fd, *argv);
Looks like someone trimmed too much and forgot to close his fd. Will
send v2.
> }
>
