tools: bpftool: protect against races with disappearing objects

On program/map show we may get an ID of an object from GETNEXT,
but the object may disappear before we call GET_FD_BY_ID.  If
that happens, ignore the object and continue.

Fixes: 71bb428fe2 ("tools: bpf: add bpftool")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Jakub Kicinski 2017-12-22 11:36:06 -08:00 committed by Daniel Borkmann
parent b3b1b65328
commit 8207c6dd47
2 changed files with 4 additions and 0 deletions

View File

@ -528,6 +528,8 @@ static int do_show(int argc, char **argv)
fd = bpf_map_get_fd_by_id(id); fd = bpf_map_get_fd_by_id(id);
if (fd < 0) { if (fd < 0) {
if (errno == ENOENT)
continue;
p_err("can't get map by id (%u): %s", p_err("can't get map by id (%u): %s",
id, strerror(errno)); id, strerror(errno));
break; break;

View File

@ -382,6 +382,8 @@ static int do_show(int argc, char **argv)
fd = bpf_prog_get_fd_by_id(id); fd = bpf_prog_get_fd_by_id(id);
if (fd < 0) { if (fd < 0) {
if (errno == ENOENT)
continue;
p_err("can't get prog by id (%u): %s", p_err("can't get prog by id (%u): %s",
id, strerror(errno)); id, strerror(errno));
err = -1; err = -1;