bpf: remove tracepoints from bpf core

tracepoints to bpf core were added as a way to provide introspection
to bpf programs and maps, but after some time it became clear that
this approach is inadequate, so prog_id, map_id and corresponding
get_next_id, get_fd_by_id, get_info_by_fd, prog_query APIs were
introduced and fully adopted by bpftool and other applications.
The tracepoints in bpf core started to rot and causing syzbot warnings:
WARNING: CPU: 0 PID: 3008 at kernel/trace/trace_event_perf.c:274
Kernel panic - not syncing: panic_on_warn set ...
perf_trace_bpf_map_keyval+0x260/0xbd0 include/trace/events/bpf.h:228
trace_bpf_map_update_elem include/trace/events/bpf.h:274 [inline]
map_update_elem kernel/bpf/syscall.c:597 [inline]
SYSC_bpf kernel/bpf/syscall.c:1478 [inline]
Hence this patch deletes tracepoints in bpf core.

Reported-by: Eric Biggers <ebiggers3@gmail.com>
Reported-by: syzbot <bot+a9dbb3c3e64b62536a4bc5ee7bbd4ca627566188@syzkaller.appspotmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/MAINTAINERS b/MAINTAINERS
index a52800867850231fde1a2d73772b27ec26dc5dee..537fd17a211b51230f1fdc7fe6c21c98a2fcf1fc 100644 (file)
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2727,7 +2727,6 @@ F:        Documentation/networking/filter.txt
 F:     Documentation/bpf/
 F:     include/linux/bpf*
 F:     include/linux/filter.h
-F:     include/trace/events/bpf.h
 F:     include/trace/events/xdp.h
 F:     include/uapi/linux/bpf*
 F:     include/uapi/linux/filter.h

diff --git a/include/linux/bpf_trace.h b/include/linux/bpf_trace.h
index e6fe98ae3794330298f834a89a7448b5fa9d730b..ddf896abcfb6ea71bd7a3e0ab298d0f3332d5b97 100644 (file)
--- a/include/linux/bpf_trace.h
+++ b/include/linux/bpf_trace.h
@@ -2,7 +2,6 @@
 #ifndef __LINUX_BPF_TRACE_H__
 #define __LINUX_BPF_TRACE_H__
 
-#include <trace/events/bpf.h>
 #include <trace/events/xdp.h>
 
 #endif /* __LINUX_BPF_TRACE_H__ */

diff --git a/include/trace/events/bpf.h b/include/trace/events/bpf.h
deleted file mode 100644 (file)
index 1501856..0000000
--- a/include/trace/events/bpf.h
+++ /dev/null
@@ -1,355 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#undef TRACE_SYSTEM
-#define TRACE_SYSTEM bpf
-
-#if !defined(_TRACE_BPF_H) || defined(TRACE_HEADER_MULTI_READ)
-#define _TRACE_BPF_H
-
-/* These are only used within the BPF_SYSCALL code */
-#ifdef CONFIG_BPF_SYSCALL
-
-#include <linux/filter.h>
-#include <linux/bpf.h>
-#include <linux/fs.h>
-#include <linux/tracepoint.h>
-
-#define __PROG_TYPE_MAP(FN)    \
-       FN(SOCKET_FILTER)       \
-       FN(KPROBE)              \
-       FN(SCHED_CLS)           \
-       FN(SCHED_ACT)           \
-       FN(TRACEPOINT)          \
-       FN(XDP)                 \
-       FN(PERF_EVENT)          \
-       FN(CGROUP_SKB)          \
-       FN(CGROUP_SOCK)         \
-       FN(LWT_IN)              \
-       FN(LWT_OUT)             \
-       FN(LWT_XMIT)
-
-#define __MAP_TYPE_MAP(FN)     \
-       FN(HASH)                \
-       FN(ARRAY)               \
-       FN(PROG_ARRAY)          \
-       FN(PERF_EVENT_ARRAY)    \
-       FN(PERCPU_HASH)         \
-       FN(PERCPU_ARRAY)        \
-       FN(STACK_TRACE)         \
-       FN(CGROUP_ARRAY)        \
-       FN(LRU_HASH)            \
-       FN(LRU_PERCPU_HASH)     \
-       FN(LPM_TRIE)
-
-#define __PROG_TYPE_TP_FN(x)   \
-       TRACE_DEFINE_ENUM(BPF_PROG_TYPE_##x);
-#define __PROG_TYPE_SYM_FN(x)  \
-       { BPF_PROG_TYPE_##x, #x },
-#define __PROG_TYPE_SYM_TAB    \
-       __PROG_TYPE_MAP(__PROG_TYPE_SYM_FN) { -1, 0 }
-__PROG_TYPE_MAP(__PROG_TYPE_TP_FN)
-
-#define __MAP_TYPE_TP_FN(x)    \
-       TRACE_DEFINE_ENUM(BPF_MAP_TYPE_##x);
-#define __MAP_TYPE_SYM_FN(x)   \
-       { BPF_MAP_TYPE_##x, #x },
-#define __MAP_TYPE_SYM_TAB     \
-       __MAP_TYPE_MAP(__MAP_TYPE_SYM_FN) { -1, 0 }
-__MAP_TYPE_MAP(__MAP_TYPE_TP_FN)
-
-DECLARE_EVENT_CLASS(bpf_prog_event,
-
-       TP_PROTO(const struct bpf_prog *prg),
-
-       TP_ARGS(prg),
-
-       TP_STRUCT__entry(
-               __array(u8, prog_tag, 8)
-               __field(u32, type)
-       ),
-
-       TP_fast_assign(
-               BUILD_BUG_ON(sizeof(__entry->prog_tag) != sizeof(prg->tag));
-               memcpy(__entry->prog_tag, prg->tag, sizeof(prg->tag));
-               __entry->type = prg->type;
-       ),
-
-       TP_printk("prog=%s type=%s",
-                 __print_hex_str(__entry->prog_tag, 8),
-                 __print_symbolic(__entry->type, __PROG_TYPE_SYM_TAB))
-);
-
-DEFINE_EVENT(bpf_prog_event, bpf_prog_get_type,
-
-       TP_PROTO(const struct bpf_prog *prg),
-
-       TP_ARGS(prg)
-);
-
-DEFINE_EVENT(bpf_prog_event, bpf_prog_put_rcu,
-
-       TP_PROTO(const struct bpf_prog *prg),
-
-       TP_ARGS(prg)
-);
-
-TRACE_EVENT(bpf_prog_load,
-
-       TP_PROTO(const struct bpf_prog *prg, int ufd),
-
-       TP_ARGS(prg, ufd),
-
-       TP_STRUCT__entry(
-               __array(u8, prog_tag, 8)
-               __field(u32, type)
-               __field(int, ufd)
-       ),
-
-       TP_fast_assign(
-               BUILD_BUG_ON(sizeof(__entry->prog_tag) != sizeof(prg->tag));
-               memcpy(__entry->prog_tag, prg->tag, sizeof(prg->tag));
-               __entry->type = prg->type;
-               __entry->ufd  = ufd;
-       ),
-
-       TP_printk("prog=%s type=%s ufd=%d",
-                 __print_hex_str(__entry->prog_tag, 8),
-                 __print_symbolic(__entry->type, __PROG_TYPE_SYM_TAB),
-                 __entry->ufd)
-);
-
-TRACE_EVENT(bpf_map_create,
-
-       TP_PROTO(const struct bpf_map *map, int ufd),
-
-       TP_ARGS(map, ufd),
-
-       TP_STRUCT__entry(
-               __field(u32, type)
-               __field(u32, size_key)
-               __field(u32, size_value)
-               __field(u32, max_entries)
-               __field(u32, flags)
-               __field(int, ufd)
-       ),
-
-       TP_fast_assign(
-               __entry->type        = map->map_type;
-               __entry->size_key    = map->key_size;
-               __entry->size_value  = map->value_size;
-               __entry->max_entries = map->max_entries;
-               __entry->flags       = map->map_flags;
-               __entry->ufd         = ufd;
-       ),
-
-       TP_printk("map type=%s ufd=%d key=%u val=%u max=%u flags=%x",
-                 __print_symbolic(__entry->type, __MAP_TYPE_SYM_TAB),
-                 __entry->ufd, __entry->size_key, __entry->size_value,
-                 __entry->max_entries, __entry->flags)
-);
-
-DECLARE_EVENT_CLASS(bpf_obj_prog,
-
-       TP_PROTO(const struct bpf_prog *prg, int ufd,
-                const struct filename *pname),
-
-       TP_ARGS(prg, ufd, pname),
-
-       TP_STRUCT__entry(
-               __array(u8, prog_tag, 8)
-               __field(int, ufd)
-               __string(path, pname->name)
-       ),
-
-       TP_fast_assign(
-               BUILD_BUG_ON(sizeof(__entry->prog_tag) != sizeof(prg->tag));
-               memcpy(__entry->prog_tag, prg->tag, sizeof(prg->tag));
-               __assign_str(path, pname->name);
-               __entry->ufd = ufd;
-       ),
-
-       TP_printk("prog=%s path=%s ufd=%d",
-                 __print_hex_str(__entry->prog_tag, 8),
-                 __get_str(path), __entry->ufd)
-);
-
-DEFINE_EVENT(bpf_obj_prog, bpf_obj_pin_prog,
-
-       TP_PROTO(const struct bpf_prog *prg, int ufd,
-                const struct filename *pname),
-
-       TP_ARGS(prg, ufd, pname)
-);
-
-DEFINE_EVENT(bpf_obj_prog, bpf_obj_get_prog,
-
-       TP_PROTO(const struct bpf_prog *prg, int ufd,
-                const struct filename *pname),
-
-       TP_ARGS(prg, ufd, pname)
-);
-
-DECLARE_EVENT_CLASS(bpf_obj_map,
-
-       TP_PROTO(const struct bpf_map *map, int ufd,
-                const struct filename *pname),
-
-       TP_ARGS(map, ufd, pname),
-
-       TP_STRUCT__entry(
-               __field(u32, type)
-               __field(int, ufd)
-               __string(path, pname->name)
-       ),
-
-       TP_fast_assign(
-               __assign_str(path, pname->name);
-               __entry->type = map->map_type;
-               __entry->ufd  = ufd;
-       ),
-
-       TP_printk("map type=%s ufd=%d path=%s",
-                 __print_symbolic(__entry->type, __MAP_TYPE_SYM_TAB),
-                 __entry->ufd, __get_str(path))
-);
-
-DEFINE_EVENT(bpf_obj_map, bpf_obj_pin_map,
-
-       TP_PROTO(const struct bpf_map *map, int ufd,
-                const struct filename *pname),
-
-       TP_ARGS(map, ufd, pname)
-);
-
-DEFINE_EVENT(bpf_obj_map, bpf_obj_get_map,
-
-       TP_PROTO(const struct bpf_map *map, int ufd,
-                const struct filename *pname),
-
-       TP_ARGS(map, ufd, pname)
-);
-
-DECLARE_EVENT_CLASS(bpf_map_keyval,
-
-       TP_PROTO(const struct bpf_map *map, int ufd,
-                const void *key, const void *val),
-
-       TP_ARGS(map, ufd, key, val),
-
-       TP_STRUCT__entry(
-               __field(u32, type)
-               __field(u32, key_len)
-               __dynamic_array(u8, key, map->key_size)
-               __field(bool, key_trunc)
-               __field(u32, val_len)
-               __dynamic_array(u8, val, map->value_size)
-               __field(bool, val_trunc)
-               __field(int, ufd)
-       ),
-
-       TP_fast_assign(
-               memcpy(__get_dynamic_array(key), key, map->key_size);
-               memcpy(__get_dynamic_array(val), val, map->value_size);
-               __entry->type      = map->map_type;
-               __entry->key_len   = min(map->key_size, 16U);
-               __entry->key_trunc = map->key_size != __entry->key_len;
-               __entry->val_len   = min(map->value_size, 16U);
-               __entry->val_trunc = map->value_size != __entry->val_len;
-               __entry->ufd       = ufd;
-       ),
-
-       TP_printk("map type=%s ufd=%d key=[%s%s] val=[%s%s]",
-                 __print_symbolic(__entry->type, __MAP_TYPE_SYM_TAB),
-                 __entry->ufd,
-                 __print_hex(__get_dynamic_array(key), __entry->key_len),
-                 __entry->key_trunc ? " ..." : "",
-                 __print_hex(__get_dynamic_array(val), __entry->val_len),
-                 __entry->val_trunc ? " ..." : "")
-);
-
-DEFINE_EVENT(bpf_map_keyval, bpf_map_lookup_elem,
-
-       TP_PROTO(const struct bpf_map *map, int ufd,
-                const void *key, const void *val),
-
-       TP_ARGS(map, ufd, key, val)
-);
-
-DEFINE_EVENT(bpf_map_keyval, bpf_map_update_elem,
-
-       TP_PROTO(const struct bpf_map *map, int ufd,
-                const void *key, const void *val),
-
-       TP_ARGS(map, ufd, key, val)
-);
-
-TRACE_EVENT(bpf_map_delete_elem,
-
-       TP_PROTO(const struct bpf_map *map, int ufd,
-                const void *key),
-
-       TP_ARGS(map, ufd, key),
-
-       TP_STRUCT__entry(
-               __field(u32, type)
-               __field(u32, key_len)
-               __dynamic_array(u8, key, map->key_size)
-               __field(bool, key_trunc)
-               __field(int, ufd)
-       ),
-
-       TP_fast_assign(
-               memcpy(__get_dynamic_array(key), key, map->key_size);
-               __entry->type      = map->map_type;
-               __entry->key_len   = min(map->key_size, 16U);
-               __entry->key_trunc = map->key_size != __entry->key_len;
-               __entry->ufd       = ufd;
-       ),
-
-       TP_printk("map type=%s ufd=%d key=[%s%s]",
-                 __print_symbolic(__entry->type, __MAP_TYPE_SYM_TAB),
-                 __entry->ufd,
-                 __print_hex(__get_dynamic_array(key), __entry->key_len),
-                 __entry->key_trunc ? " ..." : "")
-);
-
-TRACE_EVENT(bpf_map_next_key,
-
-       TP_PROTO(const struct bpf_map *map, int ufd,
-                const void *key, const void *key_next),
-
-       TP_ARGS(map, ufd, key, key_next),
-
-       TP_STRUCT__entry(
-               __field(u32, type)
-               __field(u32, key_len)
-               __dynamic_array(u8, key, map->key_size)
-               __dynamic_array(u8, nxt, map->key_size)
-               __field(bool, key_trunc)
-               __field(bool, key_null)
-               __field(int, ufd)
-       ),
-
-       TP_fast_assign(
-               if (key)
-                       memcpy(__get_dynamic_array(key), key, map->key_size);
-               __entry->key_null = !key;
-               memcpy(__get_dynamic_array(nxt), key_next, map->key_size);
-               __entry->type      = map->map_type;
-               __entry->key_len   = min(map->key_size, 16U);
-               __entry->key_trunc = map->key_size != __entry->key_len;
-               __entry->ufd       = ufd;
-       ),
-
-       TP_printk("map type=%s ufd=%d key=[%s%s] next=[%s%s]",
-                 __print_symbolic(__entry->type, __MAP_TYPE_SYM_TAB),
-                 __entry->ufd,
-                 __entry->key_null ? "NULL" : __print_hex(__get_dynamic_array(key),
-                                                          __entry->key_len),
-                 __entry->key_trunc && !__entry->key_null ? " ..." : "",
-                 __print_hex(__get_dynamic_array(nxt), __entry->key_len),
-                 __entry->key_trunc ? " ..." : "")
-);
-#endif /* CONFIG_BPF_SYSCALL */
-#endif /* _TRACE_BPF_H */
-
-#include <trace/define_trace.h>

diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 9349a5db3cf2e8c0ee241215d6c2211d9ad294de..90feeba3a1a1e3103d1c7e590f0a1c540959f4b9 100644 (file)
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -1845,9 +1845,3 @@ int __weak skb_copy_bits(const struct sk_buff *skb, int offset, void *to,
 #include <linux/bpf_trace.h>
 
 EXPORT_TRACEPOINT_SYMBOL_GPL(xdp_exception);
-
-/* These are only used within the BPF_SYSCALL code */
-#ifdef CONFIG_BPF_SYSCALL
-EXPORT_TRACEPOINT_SYMBOL_GPL(bpf_prog_get_type);
-EXPORT_TRACEPOINT_SYMBOL_GPL(bpf_prog_put_rcu);
-#endif

diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
index a41343009ccce430b05e3df4430260fcb5dcb264..ed13645bd80c48ea3e16e999cbd598182e934e63 100644 (file)
--- a/kernel/bpf/inode.c
+++ b/kernel/bpf/inode.c
@@ -429,13 +429,6 @@ int bpf_obj_pin_user(u32 ufd, const char __user *pathname)
        ret = bpf_obj_do_pin(pname, raw, type);
        if (ret != 0)
                bpf_any_put(raw, type);
-       if ((trace_bpf_obj_pin_prog_enabled() ||
-            trace_bpf_obj_pin_map_enabled()) && !ret) {
-               if (type == BPF_TYPE_PROG)
-                       trace_bpf_obj_pin_prog(raw, ufd, pname);
-               if (type == BPF_TYPE_MAP)
-                       trace_bpf_obj_pin_map(raw, ufd, pname);
-       }
 out:
        putname(pname);
        return ret;
@@ -502,15 +495,8 @@ int bpf_obj_get_user(const char __user *pathname, int flags)
        else
                goto out;
 
-       if (ret < 0) {
+       if (ret < 0)
                bpf_any_put(raw, type);
-       } else if (trace_bpf_obj_get_prog_enabled() ||
-                  trace_bpf_obj_get_map_enabled()) {
-               if (type == BPF_TYPE_PROG)
-                       trace_bpf_obj_get_prog(raw, ret, pname);
-               if (type == BPF_TYPE_MAP)
-                       trace_bpf_obj_get_map(raw, ret, pname);
-       }
 out:
        putname(pname);
        return ret;

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 0bd2944eafb9d10b81903efe7cb0bd818713e32f..263e13ede0290b7695fbaf846caaae139013eeb6 100644 (file)
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -503,7 +503,6 @@ static int map_create(union bpf_attr *attr)
                return err;
        }
 
-       trace_bpf_map_create(map, err);
        return err;
 
 free_map:
@@ -663,7 +662,6 @@ static int map_lookup_elem(union bpf_attr *attr)
        if (copy_to_user(uvalue, value, value_size) != 0)
                goto free_value;
 
-       trace_bpf_map_lookup_elem(map, ufd, key, value);
        err = 0;
 
 free_value:
@@ -760,8 +758,6 @@ static int map_update_elem(union bpf_attr *attr)
        __this_cpu_dec(bpf_prog_active);
        preempt_enable();
 out:
-       if (!err)
-               trace_bpf_map_update_elem(map, ufd, key, value);
 free_value:
        kfree(value);
 free_key:
@@ -814,8 +810,6 @@ static int map_delete_elem(union bpf_attr *attr)
        __this_cpu_dec(bpf_prog_active);
        preempt_enable();
 out:
-       if (!err)
-               trace_bpf_map_delete_elem(map, ufd, key);
        kfree(key);
 err_put:
        fdput(f);
@@ -879,7 +873,6 @@ static int map_get_next_key(union bpf_attr *attr)
        if (copy_to_user(unext_key, next_key, map->key_size) != 0)
                goto free_next_key;
 
-       trace_bpf_map_next_key(map, ufd, key, next_key);
        err = 0;
 
 free_next_key:
@@ -1027,7 +1020,6 @@ static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
        if (atomic_dec_and_test(&prog->aux->refcnt)) {
                int i;
 
-               trace_bpf_prog_put_rcu(prog);
                /* bpf_prog_free_id() must be called first */
                bpf_prog_free_id(prog, do_idr_lock);
 
@@ -1194,11 +1186,7 @@ struct bpf_prog *bpf_prog_get(u32 ufd)
 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
                                       bool attach_drv)
 {
-       struct bpf_prog *prog = __bpf_prog_get(ufd, &type, attach_drv);
-
-       if (!IS_ERR(prog))
-               trace_bpf_prog_get_type(prog);
-       return prog;
+       return __bpf_prog_get(ufd, &type, attach_drv);
 }
 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
 
@@ -1373,7 +1361,6 @@ static int bpf_prog_load(union bpf_attr *attr)
        }
 
        bpf_prog_kallsyms_add(prog);
-       trace_bpf_prog_load(prog, err);
        return err;
 
 free_used_maps: