From: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
In preparation for moving code around, change a bunch of references to
env->log (and the verbose() logging helper) to use bpf_log() and a direct
pointer to struct bpf_verifier_log. While we're touching the function
signature, mark the 'prog' argument to bpf_check_type_match() as const.
Also enhance the bpf_verifier_log_needed() check to handle NULL pointers
for the log struct so we can re-use the code with logging disabled.
Acked-by: Andrii Nakryiko <andriin@xxxxxx>
Signed-off-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
---
include/linux/bpf.h | 2 +-
include/linux/bpf_verifier.h | 5 +++-
kernel/bpf/btf.c | 6 +++--
kernel/bpf/verifier.c | 50 +++++++++++++++++++++---------------------
4 files changed, 32 insertions(+), 31 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index fc5c901c7542..1f9e7c22cc7e 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1402,7 +1402,7 @@ int btf_check_func_arg_match(struct bpf_verifier_env *env, int subprog,
struct bpf_reg_state *regs);
int btf_prepare_func_args(struct bpf_verifier_env *env, int subprog,
struct bpf_reg_state *reg);
-int btf_check_type_match(struct bpf_verifier_env *env, struct bpf_prog *prog,
+int btf_check_type_match(struct bpf_verifier_log *log, const struct bpf_prog *prog,
struct btf *btf, const struct btf_type *t);
struct bpf_prog *bpf_prog_by_id(u32 id);
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 2bb48a2c4d08..7bc9276c4ef4 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -347,8 +347,9 @@ static inline bool bpf_verifier_log_full(const struct bpf_verifier_log *log)
static inline bool bpf_verifier_log_needed(const struct bpf_verifier_log *log)
{
- return (log->level && log->ubuf && !bpf_verifier_log_full(log)) ||
- log->level == BPF_LOG_KERNEL;
+ return log &&
+ ((log->level && log->ubuf && !bpf_verifier_log_full(log)) ||
+ log->level == BPF_LOG_KERNEL);
}
#define BPF_MAX_SUBPROGS 256
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 5d3c36e13139..868c03a24d0a 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -4388,7 +4388,7 @@ static int btf_check_func_type_match(struct bpf_verifier_log *log,
}
/* Compare BTFs of given program with BTF of target program */
-int btf_check_type_match(struct bpf_verifier_env *env, struct bpf_prog *prog,
+int btf_check_type_match(struct bpf_verifier_log *log, const struct bpf_prog *prog,
struct btf *btf2, const struct btf_type *t2)
{
struct btf *btf1 = prog->aux->btf;
@@ -4396,7 +4396,7 @@ int btf_check_type_match(struct bpf_verifier_env *env, struct bpf_prog *prog,
u32 btf_id = 0;
if (!prog->aux->func_info) {
- bpf_log(&env->log, "Program extension requires BTF\n");
+ bpf_log(log, "Program extension requires BTF\n");
return -EINVAL;
}
@@ -4408,7 +4408,7 @@ int btf_check_type_match(struct bpf_verifier_env *env, struct bpf_prog *prog,
if (!t1 || !btf_type_is_func(t1))
return -EFAULT;
- return btf_check_func_type_match(&env->log, btf1, t1, btf2, t2);
+ return btf_check_func_type_match(log, btf1, t1, btf2, t2);
}
/* Compare BTF of a function with given bpf_reg_state.
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 797e2b0d8bc2..81e1bdc492f8 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -11220,6 +11220,7 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
struct bpf_prog *prog = env->prog;
bool prog_extension = prog->type == BPF_PROG_TYPE_EXT;
struct bpf_prog *tgt_prog = prog->aux->linked_prog;
+ struct bpf_verifier_log *log = &env->log;
u32 btf_id = prog->aux->attach_btf_id;
const char prefix[] = "btf_trace_";
struct btf_func_model fmodel;
@@ -11247,23 +11248,23 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
return 0;
if (!btf_id) {
- verbose(env, "Tracing programs must provide btf_id\n");
+ bpf_log(log, "Tracing programs must provide btf_id\n");
return -EINVAL;
}
btf = bpf_prog_get_target_btf(prog);
if (!btf) {
- verbose(env,
+ bpf_log(log,
"FENTRY/FEXIT program can only be attached to another program annotated with BTF\n");
return -EINVAL;
}
t = btf_type_by_id(btf, btf_id);
if (!t) {
- verbose(env, "attach_btf_id %u is invalid\n", btf_id);
+ bpf_log(log, "attach_btf_id %u is invalid\n", btf_id);
return -EINVAL;
}
tname = btf_name_by_offset(btf, t->name_off);
if (!tname) {
- verbose(env, "attach_btf_id %u doesn't have a name\n", btf_id);
+ bpf_log(log, "attach_btf_id %u doesn't have a name\n", btf_id);
return -EINVAL;
}
if (tgt_prog) {
@@ -11275,18 +11276,18 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
break;
}
if (subprog == -1) {
- verbose(env, "Subprog %s doesn't exist\n", tname);
+ bpf_log(log, "Subprog %s doesn't exist\n", tname);
return -EINVAL;
}
conservative = aux->func_info_aux[subprog].unreliable;
if (prog_extension) {
if (conservative) {
- verbose(env,
+ bpf_log(log,
"Cannot replace static functions\n");
return -EINVAL;
}
if (!prog->jit_requested) {
- verbose(env,
+ bpf_log(log,
"Extension programs should be JITed\n");
return -EINVAL;
}
@@ -11294,7 +11295,7 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
prog->expected_attach_type = tgt_prog->expected_attach_type;
}
if (!tgt_prog->jited) {
- verbose(env, "Can attach to only JITed progs\n");
+ bpf_log(log, "Can attach to only JITed progs\n");
return -EINVAL;
}
if (tgt_prog->type == prog->type) {
@@ -11302,7 +11303,7 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
* Cannot attach program extension to another extension.
* It's ok to attach fentry/fexit to extension program.
*/
- verbose(env, "Cannot recursively attach\n");
+ bpf_log(log, "Cannot recursively attach\n");
return -EINVAL;
}
if (tgt_prog->type == BPF_PROG_TYPE_TRACING &&
@@ -11324,13 +11325,13 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
* reasonable stack size. Hence extending fentry is not
* allowed.
*/
- verbose(env, "Cannot extend fentry/fexit\n");
+ bpf_log(log, "Cannot extend fentry/fexit\n");
return -EINVAL;
}
key = ((u64)aux->id) << 32 | btf_id;
} else {
if (prog_extension) {
- verbose(env, "Cannot replace kernel functions\n");
+ bpf_log(log, "Cannot replace kernel functions\n");
return -EINVAL;
}
key = btf_id;
@@ -11339,17 +11340,17 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
switch (prog->expected_attach_type) {
case BPF_TRACE_RAW_TP:
if (tgt_prog) {
- verbose(env,
+ bpf_log(log,
"Only FENTRY/FEXIT progs are attachable to another BPF prog\n");
return -EINVAL;
}
if (!btf_type_is_typedef(t)) {
- verbose(env, "attach_btf_id %u is not a typedef\n",
+ bpf_log(log, "attach_btf_id %u is not a typedef\n",
btf_id);
return -EINVAL;
}
if (strncmp(prefix, tname, sizeof(prefix) - 1)) {
- verbose(env, "attach_btf_id %u points to wrong type name %s\n",
+ bpf_log(log, "attach_btf_id %u points to wrong type name %s\n",
btf_id, tname);
return -EINVAL;
}
@@ -11372,7 +11373,7 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
return 0;
case BPF_TRACE_ITER:
if (!btf_type_is_func(t)) {
- verbose(env, "attach_btf_id %u is not a function\n",
+ bpf_log(log, "attach_btf_id %u is not a function\n",
btf_id);
return -EINVAL;
}
@@ -11383,8 +11384,7 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
prog->aux->attach_func_proto = t;
if (!bpf_iter_prog_supported(prog))
return -EINVAL;
- ret = btf_distill_func_proto(&env->log, btf, t,
- tname, &fmodel);
+ ret = btf_distill_func_proto(log, btf, t, tname, &fmodel);
return ret;
default:
if (!prog_extension)
@@ -11396,18 +11396,18 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
case BPF_TRACE_FEXIT:
prog->aux->attach_func_name = tname;
if (prog->type == BPF_PROG_TYPE_LSM) {
- ret = bpf_lsm_verify_prog(&env->log, prog);
+ ret = bpf_lsm_verify_prog(log, prog);
if (ret < 0)
return ret;
}
if (!btf_type_is_func(t)) {
- verbose(env, "attach_btf_id %u is not a function\n",
+ bpf_log(log, "attach_btf_id %u is not a function\n",
btf_id);
return -EINVAL;
}
if (prog_extension &&
- btf_check_type_match(env, prog, btf, t))
+ btf_check_type_match(log, prog, btf, t))
return -EINVAL;
t = btf_type_by_id(btf, t->type);
if (!btf_type_is_func_proto(t))
@@ -11426,7 +11426,7 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
prog->aux->attach_func_proto = NULL;
t = NULL;
}
- ret = btf_distill_func_proto(&env->log, btf, t,
+ ret = btf_distill_func_proto(log, btf, t,
tname, &tr->func.model);
if (ret < 0)
goto out;
@@ -11438,7 +11438,7 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
} else {
addr = kallsyms_lookup_name(tname);
if (!addr) {
- verbose(env,
+ bpf_log(log,
"The address of function %s cannot be found\n",
tname);
ret = -ENOENT;
@@ -11468,17 +11468,17 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
break;
}
if (ret)
- verbose(env, "%s is not sleepable\n",
+ bpf_log(log, "%s is not sleepable\n",
prog->aux->attach_func_name);
} else if (prog->expected_attach_type == BPF_MODIFY_RETURN) {
if (tgt_prog) {
- verbose(env, "can't modify return codes of BPF programs\n");
+ bpf_log(log, "can't modify return codes of BPF programs\n");
ret = -EINVAL;
goto out;
}
ret = check_attach_modify_return(prog, addr);
if (ret)
- verbose(env, "%s() is not modifiable\n",
+ bpf_log(log, "%s() is not modifiable\n",
prog->aux->attach_func_name);
}
if (ret)
