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| author | Manu Bretelle <chantr4@gmail.com> | 2022-08-01 06:24:09 -0700 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2022-08-04 14:41:13 -0700 |
| commit | d55dfe587bc0670f90564a962615723fe7749ab1 (patch) | |
| tree | 76aa182f0fc5ad10a90b8c74ed9021c1690ac09d /tools/bpf | |
| parent | 3045f42a64324d339125a8a1a1763bb9e1e08300 (diff) | |
| download | linux-d55dfe587bc0670f90564a962615723fe7749ab1.tar.gz linux-d55dfe587bc0670f90564a962615723fe7749ab1.tar.bz2 linux-d55dfe587bc0670f90564a962615723fe7749ab1.zip | |
bpftool: Remove BPF_OBJ_NAME_LEN restriction when looking up bpf program by name
bpftool was limiting the length of names to BPF_OBJ_NAME_LEN in prog_parse
fds.
Since commit b662000aff84 ("bpftool: Adding support for BTF program names")
we can get the full program name from BTF.
This patch removes the restriction of name length when running `bpftool
prog show name ${name}`.
Test:
Tested against some internal program names that were longer than
`BPF_OBJ_NAME_LEN`, here a redacted example of what was ran to test.
# previous behaviour
$ sudo bpftool prog show name some_long_program_name
Error: can't parse name
# with the patch
$ sudo ./bpftool prog show name some_long_program_name
123456789: tracing name some_long_program_name tag taghexa gpl ....
...
...
...
# too long
sudo ./bpftool prog show name $(python3 -c 'print("A"*128)')
Error: can't parse name
# not too long but no match
$ sudo ./bpftool prog show name $(python3 -c 'print("A"*127)')
Signed-off-by: Manu Bretelle <chantr4@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220801132409.4147849-1-chantr4@gmail.com
Diffstat (limited to 'tools/bpf')
| -rw-r--r-- | tools/bpf/bpftool/common.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c index 067e9ea59e3b..8727765add88 100644 --- a/tools/bpf/bpftool/common.c +++ b/tools/bpf/bpftool/common.c @@ -722,6 +722,7 @@ print_all_levels(__maybe_unused enum libbpf_print_level level, static int prog_fd_by_nametag(void *nametag, int **fds, bool tag) { + char prog_name[MAX_PROG_FULL_NAME]; unsigned int id = 0; int fd, nb_fds = 0; void *tmp; @@ -754,12 +755,20 @@ static int prog_fd_by_nametag(void *nametag, int **fds, bool tag) goto err_close_fd; } - if ((tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) || - (!tag && strncmp(nametag, info.name, BPF_OBJ_NAME_LEN))) { + if (tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) { close(fd); continue; } + if (!tag) { + get_prog_full_name(&info, fd, prog_name, + sizeof(prog_name)); + if (strncmp(nametag, prog_name, sizeof(prog_name))) { + close(fd); + continue; + } + } + if (nb_fds > 0) { tmp = realloc(*fds, (nb_fds + 1) * sizeof(int)); if (!tmp) { @@ -820,7 +829,7 @@ int prog_parse_fds(int *argc, char ***argv, int **fds) NEXT_ARGP(); name = **argv; - if (strlen(name) > BPF_OBJ_NAME_LEN - 1) { + if (strlen(name) > MAX_PROG_FULL_NAME - 1) { p_err("can't parse name"); return -1; } |