diff options
| author |   Andrii Nakryiko <andrii@kernel.org> | 2022-08-15 17:19:27 -0700 |
|---|---|---|
| committer |   Daniel Borkmann <daniel@iogearbox.net> | 2022-08-17 22:42:10 +0200 |
| commit | 813847a31447feba6119df4ee77a7c0c7a77fc72 (patch) | |
| tree | 767299922c7899e6a698bd46f63bcf09c175103c /tools/lib/bpf/skel_internal.h | |
| parent | libbpf: Fix potential NULL dereference when parsing ELF (diff) | |
| download | linux-dev-813847a31447feba6119df4ee77a7c0c7a77fc72.tar.xz linux-dev-813847a31447feba6119df4ee77a7c0c7a77fc72.zip | |
libbpf: Streamline bpf_attr and perf_event_attr initialization
Make sure that entire libbpf code base is initializing bpf_attr and
perf_event_attr with memset(0). Also for bpf_attr make sure we
clear and pass to kernel only relevant parts of bpf_attr. bpf_attr is
a huge union of independent sub-command attributes, so there is no need
to clear and pass entire union bpf_attr, which over time grows quite
a lot and for most commands this growth is completely irrelevant.
Few cases where we were relying on compiler initialization of BPF UAPI
structs (like bpf_prog_info, bpf_map_info, etc) with `= {};` were
switched to memset(0) pattern for future-proofing.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Hao Luo <haoluo@google.com>
Link: https://lore.kernel.org/bpf/20220816001929.369487-3-andrii@kernel.org
Diffstat (limited to '')
| -rw-r--r-- | tools/lib/bpf/skel_internal.h | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/tools/lib/bpf/skel_internal.h b/tools/lib/bpf/skel_internal.h index bd6f4505e7b1..365d769e0357 100644 --- a/tools/lib/bpf/skel_internal.h +++ b/tools/lib/bpf/skel_internal.h @@ -285,6 +285,8 @@ static inline int skel_link_create(int prog_fd, int target_fd, static inline int bpf_load_and_run(struct bpf_load_and_run_opts *opts) { + const size_t prog_load_attr_sz = offsetofend(union bpf_attr, fd_array); + const size_t test_run_attr_sz = offsetofend(union bpf_attr, test); int map_fd = -1, prog_fd = -1, key = 0, err; union bpf_attr attr; @@ -302,7 +304,7 @@ static inline int bpf_load_and_run(struct bpf_load_and_run_opts *opts) goto out; } - memset(&attr, 0, sizeof(attr)); + memset(&attr, 0, prog_load_attr_sz); attr.prog_type = BPF_PROG_TYPE_SYSCALL; attr.insns = (long) opts->insns; attr.insn_cnt = opts->insns_sz / sizeof(struct bpf_insn); @@ -313,18 +315,18 @@ static inline int bpf_load_and_run(struct bpf_load_and_run_opts *opts) attr.log_size = opts->ctx->log_size; attr.log_buf = opts->ctx->log_buf; attr.prog_flags = BPF_F_SLEEPABLE; - err = prog_fd = skel_sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); + err = prog_fd = skel_sys_bpf(BPF_PROG_LOAD, &attr, prog_load_attr_sz); if (prog_fd < 0) { opts->errstr = "failed to load loader prog"; set_err; goto out; } - memset(&attr, 0, sizeof(attr)); + memset(&attr, 0, test_run_attr_sz); attr.test.prog_fd = prog_fd; attr.test.ctx_in = (long) opts->ctx; attr.test.ctx_size_in = opts->ctx->sz; - err = skel_sys_bpf(BPF_PROG_RUN, &attr, sizeof(attr)); + err = skel_sys_bpf(BPF_PROG_RUN, &attr, test_run_attr_sz); if (err < 0 || (int)attr.test.retval < 0) { opts->errstr = "failed to execute loader prog"; if (err < 0) { |