| Message ID | 20210821025837.1614098-2-davemarchevsky@fb.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | bpf: implement variadic printk helper | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for bpf-next |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | warning | 6 maintainers not CCed: kafai@fb.com songliubraving@fb.com rostedt@goodmis.org mingo@redhat.com kpsingh@kernel.org john.fastabend@gmail.com |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 11849 this patch: 11849 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 40 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 11371 this patch: 11371 |
| netdev/header_inline | success | Link |
On Fri, Aug 20, 2021 at 7:59 PM Dave Marchevsky <davemarchevsky@fb.com> wrote: > > MAX_SNPRINTF_VARARGS and MAX_SEQ_PRINTF_VARARGS are used by bpf helpers > bpf_snprintf and bpf_seq_printf to limit their varargs. Both call into > bpf_bprintf_prepare for print formatting logic and have convenience > macros in libbpf (BPF_SNPRINTF, BPF_SEQ_PRINTF) which use the same > helper macros to convert varargs to a byte array. > > Changing shared functionality to support more varargs for either bpf > helper would affect the other as well, so let's combine the _VARARGS > macros to make this more obvious. > > Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com> > --- Acked-by: Andrii Nakryiko <andrii@kernel.org> > include/linux/bpf.h | 2 ++ > kernel/bpf/helpers.c | 4 +--- > kernel/trace/bpf_trace.c | 4 +--- > 3 files changed, 4 insertions(+), 6 deletions(-) > > diff --git a/include/linux/bpf.h b/include/linux/bpf.h > index f4c16f19f83e..be8d57e6e78a 100644 > --- a/include/linux/bpf.h > +++ b/include/linux/bpf.h > @@ -2216,6 +2216,8 @@ int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t, > struct btf_id_set; > bool btf_id_set_contains(const struct btf_id_set *set, u32 id); > > +#define MAX_BPRINTF_VARARGS 12 > + > int bpf_bprintf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args, > u32 **bin_buf, u32 num_args); > void bpf_bprintf_cleanup(void); > diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c > index 4e8540716187..5ce19b376ef7 100644 > --- a/kernel/bpf/helpers.c > +++ b/kernel/bpf/helpers.c > @@ -969,15 +969,13 @@ int bpf_bprintf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args, > return err; > } > > -#define MAX_SNPRINTF_VARARGS 12 > - > BPF_CALL_5(bpf_snprintf, char *, str, u32, str_size, char *, fmt, > const void *, data, u32, data_len) > { > int err, num_args; > u32 *bin_args; > > - if (data_len % 8 || data_len > MAX_SNPRINTF_VARARGS * 8 || > + if (data_len % 8 || data_len > MAX_BPRINTF_VARARGS * 8 || > (data_len && !data)) > return -EINVAL; > num_args = data_len / 8; > diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c > index cbc73c08c4a4..2cf4bfa1ab7b 100644 > --- a/kernel/trace/bpf_trace.c > +++ b/kernel/trace/bpf_trace.c > @@ -414,15 +414,13 @@ const struct bpf_func_proto *bpf_get_trace_printk_proto(void) > return &bpf_trace_printk_proto; > } > > -#define MAX_SEQ_PRINTF_VARARGS 12 > - > BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size, > const void *, data, u32, data_len) > { > int err, num_args; > u32 *bin_args; > > - if (data_len & 7 || data_len > MAX_SEQ_PRINTF_VARARGS * 8 || > + if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 || > (data_len && !data)) > return -EINVAL; > num_args = data_len / 8; > -- > 2.30.2 >
diff --git a/include/linux/bpf.h b/include/linux/bpf.h index f4c16f19f83e..be8d57e6e78a 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -2216,6 +2216,8 @@ int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t, struct btf_id_set; bool btf_id_set_contains(const struct btf_id_set *set, u32 id); +#define MAX_BPRINTF_VARARGS 12 + int bpf_bprintf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args, u32 **bin_buf, u32 num_args); void bpf_bprintf_cleanup(void); diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 4e8540716187..5ce19b376ef7 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -969,15 +969,13 @@ int bpf_bprintf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args, return err; } -#define MAX_SNPRINTF_VARARGS 12 - BPF_CALL_5(bpf_snprintf, char *, str, u32, str_size, char *, fmt, const void *, data, u32, data_len) { int err, num_args; u32 *bin_args; - if (data_len % 8 || data_len > MAX_SNPRINTF_VARARGS * 8 || + if (data_len % 8 || data_len > MAX_BPRINTF_VARARGS * 8 || (data_len && !data)) return -EINVAL; num_args = data_len / 8; diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index cbc73c08c4a4..2cf4bfa1ab7b 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -414,15 +414,13 @@ const struct bpf_func_proto *bpf_get_trace_printk_proto(void) return &bpf_trace_printk_proto; } -#define MAX_SEQ_PRINTF_VARARGS 12 - BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size, const void *, data, u32, data_len) { int err, num_args; u32 *bin_args; - if (data_len & 7 || data_len > MAX_SEQ_PRINTF_VARARGS * 8 || + if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 || (data_len && !data)) return -EINVAL; num_args = data_len / 8;
MAX_SNPRINTF_VARARGS and MAX_SEQ_PRINTF_VARARGS are used by bpf helpers bpf_snprintf and bpf_seq_printf to limit their varargs. Both call into bpf_bprintf_prepare for print formatting logic and have convenience macros in libbpf (BPF_SNPRINTF, BPF_SEQ_PRINTF) which use the same helper macros to convert varargs to a byte array. Changing shared functionality to support more varargs for either bpf helper would affect the other as well, so let's combine the _VARARGS macros to make this more obvious. Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com> --- include/linux/bpf.h | 2 ++ kernel/bpf/helpers.c | 4 +--- kernel/trace/bpf_trace.c | 4 +--- 3 files changed, 4 insertions(+), 6 deletions(-)