Started by Martin KaFai Lau on Mar 24, 2018 · 4 messages from 2 authors · Last reply Mar 26, 2018
2 patches, 2 files
+23 −13
Status: Reviewed.
open the first message on its own page
M Martin KaFai Lau #
This patch set has some changes and clean-up works for
the bpf_verifier_log. They are the prep works for the
BTF (BPF Type Format).
Martin KaFai Lau (2):
bpf: Rename bpf_verifer_log
bpf: Add bpf_verifier_vlog() and bpf_verifier_log_needed()
include/linux/bpf_verifier.h | 13 ++++++++++---
kernel/bpf/verifier.c | 21 ++++++++++++---------
2 files changed, 22 insertions(+), 12 deletions(-)
--
2.9.5M Martin KaFai Lau replied to Martin KaFai Lau #
bpf_verifer_log => bpf_verifier_log Signed-off-by: Martin KaFai Lau <redacted> Acked-by: Alexei Starovoitov <redacted> --- include/linux/bpf_verifier.h | 6 +++--- kernel/bpf/verifier.c | 4 ++-- 2 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 6b66cd1aa0b9..c30668414b22 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h@@ -153,7 +153,7 @@ struct bpf_insn_aux_data { #define BPF_VERIFIER_TMP_LOG_SIZE 1024 -struct bpf_verifer_log { +struct bpf_verifier_log { u32 level; char kbuf[BPF_VERIFIER_TMP_LOG_SIZE]; char __user *ubuf;
@@ -161,7 +161,7 @@ struct bpf_verifer_log { u32 len_total; }; -static inline bool bpf_verifier_log_full(const struct bpf_verifer_log *log) +static inline bool bpf_verifier_log_full(const struct bpf_verifier_log *log) { return log->len_used >= log->len_total - 1; }
@@ -185,7 +185,7 @@ struct bpf_verifier_env { bool allow_ptr_leaks; bool seen_direct_write; struct bpf_insn_aux_data *insn_aux_data; /* array of per-insn state */ - struct bpf_verifer_log log; + struct bpf_verifier_log log; u32 subprog_starts[BPF_MAX_SUBPROGS]; /* computes the stack depth of each bpf function */ u16 subprog_stack_depth[BPF_MAX_SUBPROGS + 1];
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index e93a6e48641b..1e84e02ff733 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c@@ -171,7 +171,7 @@ static DEFINE_MUTEX(bpf_verifier_lock); static void log_write(struct bpf_verifier_env *env, const char *fmt, va_list args) { - struct bpf_verifer_log *log = &env->log; + struct bpf_verifier_log *log = &env->log; unsigned int n; if (!log->level || !log->ubuf || bpf_verifier_log_full(log))
@@ -5611,7 +5611,7 @@ static void free_states(struct bpf_verifier_env *env) int bpf_check(struct bpf_prog **prog, union bpf_attr *attr) { struct bpf_verifier_env *env; - struct bpf_verifer_log *log; + struct bpf_verifier_log *log; int ret = -EINVAL; /* no program is valid */
--
2.9.5M Martin KaFai Lau replied to Martin KaFai Lau #
The BTF (BPF Type Format) verifier needs to reuse the current
BPF verifier log. Hence, it requires the following changes:
(1) Expose log_write() in verifier.c for other users.
Its name is renamed to bpf_verifier_vlog().
(2) The BTF verifier also needs to check
'log->level && log->ubuf && !bpf_verifier_log_full(log);'
independently outside of the current log_write(). It is
because the BTF verifier will do one-check before
making multiple calls to btf_verifier_vlog to log
the details of a type.
Hence, this check is also re-factored to a new function
bpf_verifier_log_needed(). Since it is re-factored,
we can check it before va_start() in the current
bpf_verifier_log_write() and verbose().
Signed-off-by: Martin KaFai Lau <redacted>
Acked-by: Alexei Starovoitov <redacted>
---
include/linux/bpf_verifier.h | 7 +++++++
kernel/bpf/verifier.c | 19 +++++++++++--------
2 files changed, 18 insertions(+), 8 deletions(-)
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index c30668414b22..7e61c395fddf 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h@@ -166,6 +166,11 @@ static inline bool bpf_verifier_log_full(const struct bpf_verifier_log *log) return log->len_used >= log->len_total - 1; } +static inline bool bpf_verifier_log_needed(const struct bpf_verifier_log *log) +{ + return log->level && log->ubuf && !bpf_verifier_log_full(log); +} + #define BPF_MAX_SUBPROGS 256 /* single container for all structs
@@ -192,6 +197,8 @@ struct bpf_verifier_env { u32 subprog_cnt; }; +void bpf_verifier_vlog(struct bpf_verifier_log *log, const char *fmt, + va_list args); __printf(2, 3) void bpf_verifier_log_write(struct bpf_verifier_env *env, const char *fmt, ...);
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 1e84e02ff733..8acd2207e412 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c@@ -168,15 +168,11 @@ struct bpf_call_arg_meta { static DEFINE_MUTEX(bpf_verifier_lock); -static void log_write(struct bpf_verifier_env *env, const char *fmt, - va_list args) +void bpf_verifier_vlog(struct bpf_verifier_log *log, const char *fmt, + va_list args) { - struct bpf_verifier_log *log = &env->log; unsigned int n; - if (!log->level || !log->ubuf || bpf_verifier_log_full(log)) - return; - n = vscnprintf(log->kbuf, BPF_VERIFIER_TMP_LOG_SIZE, fmt, args); WARN_ONCE(n >= BPF_VERIFIER_TMP_LOG_SIZE - 1,
@@ -200,18 +196,25 @@ __printf(2, 3) void bpf_verifier_log_write(struct bpf_verifier_env *env, { va_list args; + if (!bpf_verifier_log_needed(&env->log)) + return; + va_start(args, fmt); - log_write(env, fmt, args); + bpf_verifier_vlog(&env->log, fmt, args); va_end(args); } EXPORT_SYMBOL_GPL(bpf_verifier_log_write); __printf(2, 3) static void verbose(void *private_data, const char *fmt, ...) { + struct bpf_verifier_env *env = private_data; va_list args; + if (!bpf_verifier_log_needed(&env->log)) + return; + va_start(args, fmt); - log_write(private_data, fmt, args); + bpf_verifier_vlog(&env->log, fmt, args); va_end(args); }
--
2.9.5D Daniel Borkmann replied to Martin KaFai Lau #
On 03/24/2018 07:44 PM, Martin KaFai Lau wrote:
This patch set has some changes and clean-up works for the bpf_verifier_log. They are the prep works for the BTF (BPF Type Format). Martin KaFai Lau (2): bpf: Rename bpf_verifer_log bpf: Add bpf_verifier_vlog() and bpf_verifier_log_needed() include/linux/bpf_verifier.h | 13 ++++++++++--- kernel/bpf/verifier.c | 21 ++++++++++++--------- 2 files changed, 22 insertions(+), 12 deletions(-)
Applied to bpf-next, thanks Martin!