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author | Rong Tao <rongtao@cestc.cn> | 2022-11-05 14:48:00 +0800 |
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committer | Andrii Nakryiko <andrii@kernel.org> | 2022-11-07 17:13:35 -0800 |
commit | e5659e4e19e49f1eac58bb07ce8bc2d78a89fe65 (patch) | |
tree | 48fd4f7279c5948d2f489a45e60d4a73db0f7f5e /samples/bpf/sockex3_user.c | |
parent | e8f50c4f0c14214b6430b8b3493654a286681a2b (diff) | |
download | linux-e5659e4e19e49f1eac58bb07ce8bc2d78a89fe65.tar.gz linux-e5659e4e19e49f1eac58bb07ce8bc2d78a89fe65.tar.bz2 linux-e5659e4e19e49f1eac58bb07ce8bc2d78a89fe65.zip |
samples/bpf: Fix sockex3 error: Missing BPF prog type
since commit 450b167fb9be("libbpf: clean up SEC() handling"),
sec_def_matches() does not recognize "socket/xxx" as "socket", therefore,
the BPF program type is not recognized.
Instead of sockex3_user.c parsing section names to get the BPF program fd.
We use the program array map to assign a static index to each BPF program
(get inspired by selftests/bpf progs/test_prog_array_init.c).
Therefore, use SEC("socket") as section name instead of SEC("socket/xxx"),
so that the BPF program is parsed to SOCKET_FILTER type. The "missing BPF
prog type" problem is solved.
How to reproduce this error:
$ cd samples/bpf
$ sudo ./sockex3
libbpf: prog 'bpf_func_PARSE_IP': missing BPF prog type, check ELF section name 'socket/3'
libbpf: prog 'bpf_func_PARSE_IP': failed to load: -22
libbpf: failed to load object './sockex3_kern.o'
ERROR: loading BPF object file failed
Signed-off-by: Rong Tao <rongtao@cestc.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/tencent_EBA3C18864069E42175946973C2ACBAF5408@qq.com
Diffstat (limited to 'samples/bpf/sockex3_user.c')
-rw-r--r-- | samples/bpf/sockex3_user.c | 23 |
1 files changed, 10 insertions, 13 deletions
diff --git a/samples/bpf/sockex3_user.c b/samples/bpf/sockex3_user.c index cd6fa79df900..56044acbd25d 100644 --- a/samples/bpf/sockex3_user.c +++ b/samples/bpf/sockex3_user.c @@ -24,10 +24,9 @@ struct pair { int main(int argc, char **argv) { - int i, sock, key, fd, main_prog_fd, jmp_table_fd, hash_map_fd; + int i, sock, fd, main_prog_fd, hash_map_fd; struct bpf_program *prog; struct bpf_object *obj; - const char *section; char filename[256]; FILE *f; @@ -45,26 +44,24 @@ int main(int argc, char **argv) goto cleanup; } - jmp_table_fd = bpf_object__find_map_fd_by_name(obj, "jmp_table"); hash_map_fd = bpf_object__find_map_fd_by_name(obj, "hash_map"); - if (jmp_table_fd < 0 || hash_map_fd < 0) { + if (hash_map_fd < 0) { fprintf(stderr, "ERROR: finding a map in obj file failed\n"); goto cleanup; } + /* find BPF main program */ + main_prog_fd = 0; bpf_object__for_each_program(prog, obj) { fd = bpf_program__fd(prog); - section = bpf_program__section_name(prog); - if (sscanf(section, "socket/%d", &key) != 1) { - fprintf(stderr, "ERROR: finding prog failed\n"); - goto cleanup; - } - - if (key == 0) + if (!strcmp(bpf_program__name(prog), "main_prog")) main_prog_fd = fd; - else - bpf_map_update_elem(jmp_table_fd, &key, &fd, BPF_ANY); + } + + if (main_prog_fd == 0) { + fprintf(stderr, "ERROR: can't find main_prog\n"); + goto cleanup; } sock = open_raw_sock("lo"); |