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author | Alexei Starovoitov <ast@kernel.org> | 2021-12-01 10:10:26 -0800 |
---|---|---|
committer | Andrii Nakryiko <andrii@kernel.org> | 2021-12-02 11:18:34 -0800 |
commit | 29db4bea1d10b73749d7992c1fc9ac13499e8871 (patch) | |
tree | 31f7d97402820d1003f9a6e21c0a2b85cafe7e4f /kernel | |
parent | 8293eb995f349aed28006792cad4cb48091919dd (diff) | |
download | linux-stable-29db4bea1d10b73749d7992c1fc9ac13499e8871.tar.gz linux-stable-29db4bea1d10b73749d7992c1fc9ac13499e8871.tar.bz2 linux-stable-29db4bea1d10b73749d7992c1fc9ac13499e8871.zip |
bpf: Prepare relo_core.c for kernel duty.
Make relo_core.c to be compiled for the kernel and for user space libbpf.
Note the patch is reducing BPF_CORE_SPEC_MAX_LEN from 64 to 32.
This is the maximum number of nested structs and arrays.
For example:
struct sample {
int a;
struct {
int b[10];
};
};
struct sample *s = ...;
int *y = &s->b[5];
This field access is encoded as "0:1:0:5" and spec len is 4.
The follow up patch might bump it back to 64.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211201181040.23337-4-alexei.starovoitov@gmail.com
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/bpf/Makefile | 4 | ||||
-rw-r--r-- | kernel/bpf/btf.c | 26 |
2 files changed, 30 insertions, 0 deletions
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index cf6ca339f3cd..c1a9be6a4b9f 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -36,3 +36,7 @@ obj-$(CONFIG_BPF_SYSCALL) += bpf_struct_ops.o obj-${CONFIG_BPF_LSM} += bpf_lsm.o endif obj-$(CONFIG_BPF_PRELOAD) += preload/ + +obj-$(CONFIG_BPF_SYSCALL) += relo_core.o +$(obj)/relo_core.o: $(srctree)/tools/lib/bpf/relo_core.c FORCE + $(call if_changed_rule,cc_o_c) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index f4119a99da7b..c79595aad55b 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -6413,3 +6413,29 @@ bool bpf_check_mod_kfunc_call(struct kfunc_btf_id_list *klist, u32 kfunc_id, DEFINE_KFUNC_BTF_ID_LIST(bpf_tcp_ca_kfunc_list); DEFINE_KFUNC_BTF_ID_LIST(prog_test_kfunc_list); + +int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id, + const struct btf *targ_btf, __u32 targ_id) +{ + return -EOPNOTSUPP; +} + +static bool bpf_core_is_flavor_sep(const char *s) +{ + /* check X___Y name pattern, where X and Y are not underscores */ + return s[0] != '_' && /* X */ + s[1] == '_' && s[2] == '_' && s[3] == '_' && /* ___ */ + s[4] != '_'; /* Y */ +} + +size_t bpf_core_essential_name_len(const char *name) +{ + size_t n = strlen(name); + int i; + + for (i = n - 5; i >= 0; i--) { + if (bpf_core_is_flavor_sep(name + i)) + return i + 1; + } + return n; +} |