[PATCH bpf-next 17/29] bpf: Resolve id in bpf_tramp_id_single
flat view
STALE1778d
From: Jiri Olsa <hidden>
Date: 2021-11-18 11:28:47
Also in:
bpf
Subsystem:
bpf [core], bpf [general] (safe dynamic programs and tools), the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Linus Torvalds
Moving the id resolving in the bpf_tramp_id_single function so it's centralized together with the trampoline's allocation and init. Signed-off-by: Jiri Olsa <jolsa@kernel.org> --- include/linux/bpf.h | 3 ++- kernel/bpf/syscall.c | 21 ++++++--------------- kernel/bpf/trampoline.c | 18 +++++++++++++++--- kernel/bpf/verifier.c | 4 +--- 4 files changed, 24 insertions(+), 22 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 894ee812e213..dda24339e4b1 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h@@ -756,7 +756,8 @@ void bpf_tramp_id_free(struct bpf_tramp_id *id); bool bpf_tramp_id_is_empty(struct bpf_tramp_id *id); int bpf_tramp_id_is_equal(struct bpf_tramp_id *a, struct bpf_tramp_id *b); struct bpf_tramp_id *bpf_tramp_id_single(const struct bpf_prog *tgt_prog, - struct btf *btf, u32 btf_id); + struct bpf_prog *prog, u32 btf_id, + struct bpf_attach_target_info *tgt_info); int bpf_trampoline_link_prog(struct bpf_tramp_node *node, struct bpf_trampoline *tr); int bpf_trampoline_unlink_prog(struct bpf_tramp_node *node, struct bpf_trampoline *tr); void bpf_trampoline_put(struct bpf_trampoline *tr);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 8109b0fc7d2f..0acf6cb0fdc7 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c@@ -2773,9 +2773,9 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog, goto out_put_prog; } - id = bpf_tramp_id_single(tgt_prog, NULL, btf_id); - if (!id) { - err = -ENOMEM; + id = bpf_tramp_id_single(tgt_prog, prog, btf_id, NULL); + if (IS_ERR(id)) { + err = PTR_ERR(id); goto out_put_prog; } }
@@ -2828,9 +2828,9 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog, } btf_id = prog->aux->attach_btf_id; - id = bpf_tramp_id_single(NULL, prog->aux->attach_btf, btf_id); - if (!id) { - err = -ENOMEM; + id = bpf_tramp_id_single(NULL, prog, btf_id, NULL); + if (IS_ERR(id)) { + err = PTR_ERR(id); goto out_unlock; } }
@@ -2842,15 +2842,6 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog, * different from the destination specified at load time, we * need a new trampoline and a check for compatibility */ - struct bpf_attach_target_info tgt_info = {}; - - err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id, - &tgt_info); - if (err) - goto out_unlock; - - id->addr[0] = (void *) tgt_info.tgt_addr; - attach = bpf_tramp_attach(id, tgt_prog, prog); if (IS_ERR(attach)) { err = PTR_ERR(attach);
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 4a4ef9396b7e..e6a73088ecee 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c@@ -105,18 +105,30 @@ struct bpf_tramp_id *bpf_tramp_id_alloc(u32 max) } struct bpf_tramp_id *bpf_tramp_id_single(const struct bpf_prog *tgt_prog, - struct btf *btf, u32 btf_id) + struct bpf_prog *prog, u32 btf_id, + struct bpf_attach_target_info *tgt_info) { struct bpf_tramp_id *id; + if (!tgt_info) { + struct bpf_attach_target_info __tgt_info = {}; + int err; + + tgt_info = &__tgt_info; + err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id, + tgt_info); + if (err) + return ERR_PTR(err); + } id = bpf_tramp_id_alloc(1); if (!id) - return NULL; + return ERR_PTR(-ENOMEM); if (tgt_prog) id->obj_id = tgt_prog->aux->id; else - id->obj_id = btf_obj_id(btf); + id->obj_id = btf_obj_id(prog->aux->attach_btf); id->id[0] = btf_id; + id->addr[0] = (void *) tgt_info->tgt_addr; id->cnt = 1; return id; }
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 9914487f2281..8d56d43489aa 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c@@ -13995,12 +13995,10 @@ static int check_attach_btf_id(struct bpf_verifier_env *env) return -EINVAL; } - id = bpf_tramp_id_single(NULL, prog->aux->attach_btf, btf_id); + id = bpf_tramp_id_single(tgt_prog, prog, btf_id, &tgt_info); if (!id) return -ENOMEM; - id->addr[0] = (void *) tgt_info.tgt_addr; - attach = bpf_tramp_attach(id, tgt_prog, prog); if (IS_ERR(attach)) { bpf_tramp_id_free(id);
--
2.31.1