bpf: Add a common helper bpf_copy_to_user()

Add a common helper bpf_copy_to_user(), which will be used at multiple
places.
No functional change.

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230709025630.3735-8-laoar.shao@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Yafang Shao 2023-07-09 02:56:27 +00:00 committed by Alexei Starovoitov
parent cd3910d005
commit 57d4853765
1 changed files with 20 additions and 14 deletions

View File

@ -3295,6 +3295,25 @@ static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
raw_tp_link->btp->tp->name);
}
static int bpf_copy_to_user(char __user *ubuf, const char *buf, u32 ulen,
u32 len)
{
if (ulen >= len + 1) {
if (copy_to_user(ubuf, buf, len + 1))
return -EFAULT;
} else {
char zero = '\0';
if (copy_to_user(ubuf, buf, ulen - 1))
return -EFAULT;
if (put_user(zero, ubuf + ulen - 1))
return -EFAULT;
return -ENOSPC;
}
return 0;
}
static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
struct bpf_link_info *info)
{
@ -3313,20 +3332,7 @@ static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
if (!ubuf)
return 0;
if (ulen >= tp_len + 1) {
if (copy_to_user(ubuf, tp_name, tp_len + 1))
return -EFAULT;
} else {
char zero = '\0';
if (copy_to_user(ubuf, tp_name, ulen - 1))
return -EFAULT;
if (put_user(zero, ubuf + ulen - 1))
return -EFAULT;
return -ENOSPC;
}
return 0;
return bpf_copy_to_user(ubuf, tp_name, ulen, tp_len);
}
static const struct bpf_link_ops bpf_raw_tp_link_lops = {