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| author |  Jiri Olsa <jolsa@kernel.org>
| 2020-08-25 21:21:19 +0200 |
|---|---|---|
| committer |  Alexei Starovoitov <ast@kernel.org>
| 2020-08-25 15:37:41 -0700 |
| commit | eae2e83e62633a2659e3bc690facba1c2fc9c45b (patch) | |
| tree | 22f56b258d678de272acfe98e53fb98c01ec10ad /kernel | |
| parent | bpf: Add btf_struct_ids_match function (diff) | |
| download | linux-eae2e83e62633a2659e3bc690facba1c2fc9c45b.tar.gz linux-eae2e83e62633a2659e3bc690facba1c2fc9c45b.tar.bz2 linux-eae2e83e62633a2659e3bc690facba1c2fc9c45b.zip | |
bpf: Add BTF_SET_START/END macros
Adding support to define sorted set of BTF ID values.
Following defines sorted set of BTF ID values:
BTF_SET_START(btf_allowlist_d_path)
BTF_ID(func, vfs_truncate)
BTF_ID(func, vfs_fallocate)
BTF_ID(func, dentry_open)
BTF_ID(func, vfs_getattr)
BTF_ID(func, filp_close)
BTF_SET_END(btf_allowlist_d_path)
It defines following 'struct btf_id_set' variable to access
values and count:
struct btf_id_set btf_allowlist_d_path;
Adding 'allowed' callback to struct bpf_func_proto, to allow
verifier the check on allowed callers.
Adding btf_id_set_contains function, which will be used by
allowed callbacks to verify the caller's BTF ID value is
within allowed set.
Also removing extra '\' in __BTF_ID_LIST macro.
Added BTF_SET_START_GLOBAL macro for global sets.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-10-jolsa@kernel.org
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/btf.c | 14 | ||||
| -rw-r--r-- | kernel/bpf/verifier.c | 5 |
2 files changed, 19 insertions, 0 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index df966acaaeb1..f9ac6935ab3c 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -21,6 +21,8 @@ #include <linux/btf_ids.h> #include <linux/skmsg.h> #include <linux/perf_event.h> +#include <linux/bsearch.h> +#include <linux/btf_ids.h> #include <net/sock.h> /* BTF (BPF Type Format) is the meta data format which describes @@ -4762,3 +4764,15 @@ u32 btf_id(const struct btf *btf) { return btf->id; } + +static int btf_id_cmp_func(const void *a, const void *b) +{ + const int *pa = a, *pb = b; + + return *pa - *pb; +} + +bool btf_id_set_contains(struct btf_id_set *set, u32 id) +{ + return bsearch(&id, set->ids, set->cnt, sizeof(u32), btf_id_cmp_func) != NULL; +} diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index f003cee75d22..7e5908b83ec7 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -4859,6 +4859,11 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn return -EINVAL; } + if (fn->allowed && !fn->allowed(env->prog)) { + verbose(env, "helper call is not allowed in probe\n"); + return -EINVAL; + } + /* With LD_ABS/IND some JITs save/restore skb from r1. */ changes_data = bpf_helper_changes_pkt_data(fn->func); if (changes_data && fn->arg1_type != ARG_PTR_TO_CTX) { |