bpf: Expose check_uarg_tail_zero()

This patch exposes check_uarg_tail_zero() which will
be reused by a later BTF patch.  Its name is changed to
bpf_check_uarg_tail_zero().

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Martin KaFai Lau 2018-05-22 15:03:31 -07:00 committed by Daniel Borkmann
parent 3fb48d881d
commit dcab51f19b
2 changed files with 9 additions and 7 deletions

View File

@ -463,6 +463,8 @@ int bpf_fd_htab_map_update_elem(struct bpf_map *map, struct file *map_file,
int bpf_fd_htab_map_lookup_elem(struct bpf_map *map, void *key, u32 *value);
int bpf_get_file_flag(int flags);
int bpf_check_uarg_tail_zero(void __user *uaddr, size_t expected_size,
size_t actual_size);
/* memcpy that is used with 8-byte aligned pointers, power-of-8 size and
* forced to use 'long' read/writes to try to atomically copy long counters.

View File

@ -65,9 +65,9 @@ static const struct bpf_map_ops * const bpf_map_types[] = {
* copy_from_user() call. However, this is not a concern since this function is
* meant to be a future-proofing of bits.
*/
static int check_uarg_tail_zero(void __user *uaddr,
size_t expected_size,
size_t actual_size)
int bpf_check_uarg_tail_zero(void __user *uaddr,
size_t expected_size,
size_t actual_size)
{
unsigned char __user *addr;
unsigned char __user *end;
@ -1899,7 +1899,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
u32 ulen;
int err;
err = check_uarg_tail_zero(uinfo, sizeof(info), info_len);
err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
if (err)
return err;
info_len = min_t(u32, sizeof(info), info_len);
@ -1998,7 +1998,7 @@ static int bpf_map_get_info_by_fd(struct bpf_map *map,
u32 info_len = attr->info.info_len;
int err;
err = check_uarg_tail_zero(uinfo, sizeof(info), info_len);
err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
if (err)
return err;
info_len = min_t(u32, sizeof(info), info_len);
@ -2038,7 +2038,7 @@ static int bpf_btf_get_info_by_fd(struct btf *btf,
u32 info_len = attr->info.info_len;
int err;
err = check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len);
err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len);
if (err)
return err;
@ -2110,7 +2110,7 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz
if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN))
return -EPERM;
err = check_uarg_tail_zero(uattr, sizeof(attr), size);
err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
if (err)
return err;
size = min_t(u32, size, sizeof(attr));