From: Song Liu <songliubraving@fb.com>
To: <netdev@vger.kernel.org>
Cc: <kernel-team@fb.com>, Song Liu <songliubraving@fb.com>,
<ast@kernel.org>, <daniel@iogearbox.net>,
<sandipan@linux.vnet.ibm.com>
Subject: [PATCH v2 bpf 3/3] bpf: show main program address and length in bpf_prog_info
Date: Fri, 2 Nov 2018 10:16:17 -0700 [thread overview]
Message-ID: <20181102171617.310178-4-songliubraving@fb.com> (raw)
In-Reply-To: <20181102171617.310178-1-songliubraving@fb.com>
Currently, when there is no subprog (prog->aux->func_cnt == 0),
bpf_prog_info does not return any jited_ksyms or jited_func_lens. This
patch adds main program address (prog->bpf_func) and main program
length (prog->jited_len) to bpf_prog_info.
Signed-off-by: Song Liu <songliubraving@fb.com>
---
kernel/bpf/syscall.c | 33 ++++++++++++++++++++++++---------
1 file changed, 24 insertions(+), 9 deletions(-)
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 34a9eef5992c..9418174c276c 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2158,11 +2158,11 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
}
ulen = info.nr_jited_ksyms;
- info.nr_jited_ksyms = prog->aux->func_cnt;
+ info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
if (info.nr_jited_ksyms && ulen) {
if (bpf_dump_raw_ok()) {
+ unsigned long ksym_addr;
u64 __user *user_ksyms;
- ulong ksym_addr;
u32 i;
/* copy the address of the kernel symbol
@@ -2170,9 +2170,17 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
*/
ulen = min_t(u32, info.nr_jited_ksyms, ulen);
user_ksyms = u64_to_user_ptr(info.jited_ksyms);
- for (i = 0; i < ulen; i++) {
- ksym_addr = (ulong) prog->aux->func[i]->bpf_func;
- if (put_user((u64) ksym_addr, &user_ksyms[i]))
+ if (prog->aux->func_cnt) {
+ for (i = 0; i < ulen; i++) {
+ ksym_addr = (unsigned long)
+ prog->aux->func[i]->bpf_func;
+ if (put_user((u64) ksym_addr,
+ &user_ksyms[i]))
+ return -EFAULT;
+ }
+ } else {
+ ksym_addr = (unsigned long) prog->bpf_func;
+ if (put_user((u64) ksym_addr, &user_ksyms[0]))
return -EFAULT;
}
} else {
@@ -2181,7 +2189,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
}
ulen = info.nr_jited_func_lens;
- info.nr_jited_func_lens = prog->aux->func_cnt;
+ info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
if (info.nr_jited_func_lens && ulen) {
if (bpf_dump_raw_ok()) {
u32 __user *user_lens;
@@ -2190,9 +2198,16 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
/* copy the JITed image lengths for each function */
ulen = min_t(u32, info.nr_jited_func_lens, ulen);
user_lens = u64_to_user_ptr(info.jited_func_lens);
- for (i = 0; i < ulen; i++) {
- func_len = prog->aux->func[i]->jited_len;
- if (put_user(func_len, &user_lens[i]))
+ if (prog->aux->func_cnt) {
+ for (i = 0; i < ulen; i++) {
+ func_len =
+ prog->aux->func[i]->jited_len;
+ if (put_user(func_len, &user_lens[i]))
+ return -EFAULT;
+ }
+ } else {
+ func_len = prog->jited_len;
+ if (put_user(func_len, &user_lens[0]))
return -EFAULT;
}
} else {
--
2.17.1
next prev parent reply other threads:[~2018-11-03 2:25 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-02 17:16 [PATCH v2 bpf 0/3] show more accurrate bpf program address Song Liu
2018-11-02 17:16 ` [PATCH v2 bpf 1/3] bpf: show real jited prog address in /proc/kallsyms Song Liu
2018-11-02 17:16 ` [PATCH v2 bpf 2/3] bpf: show real jited address in bpf_prog_info->jited_ksyms Song Liu
2018-11-02 17:16 ` Song Liu [this message]
2018-11-02 20:45 ` [PATCH v2 bpf 0/3] show more accurrate bpf program address Daniel Borkmann
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