diff options
| author | Dmitry Safonov | 2018-09-03 22:40:51 +0100 |
|---|---|---|
| committer | David S. Miller | 2018-09-05 22:11:33 -0700 |
| commit | 428f944bd58607021b5a1f85d145c0b50f908c6f (patch) | |
| tree | 9eb7a6c61b82a4a901ab728317ce3cf39fbcbd6b /net/netlink | |
| parent | fa788d986a3aac5069378ed04697bd06f83d3488 (diff) | |
netlink: Make groups check less stupid in netlink_bind()
As Linus noted, the test for 0 is needless, groups type can follow the
usual kernel style and 8*sizeof(unsigned long) is BITS_PER_LONG:
> The code [..] isn't technically incorrect...
> But it is stupid.
> Why stupid? Because the test for 0 is pointless.
>
> Just doing
> if (nlk->ngroups < 8*sizeof(groups))
> groups &= (1UL << nlk->ngroups) - 1;
>
> would have been fine and more understandable, since the "mask by shift
> count" already does the right thing for a ngroups value of 0. Now that
> test for zero makes me go "what's special about zero?". It turns out
> that the answer to that is "nothing".
[..]
> The type of "groups" is kind of silly too.
>
> Yeah, "long unsigned int" isn't _technically_ wrong. But we normally
> call that type "unsigned long".
Cleanup my piece of pointlessness.
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: netdev@vger.kernel.org
Fairly-blamed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/netlink')
| -rw-r--r-- | net/netlink/af_netlink.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 930d17fa906c..b4a29bcc33b9 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -993,7 +993,7 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr, struct netlink_sock *nlk = nlk_sk(sk); struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; int err = 0; - long unsigned int groups = nladdr->nl_groups; + unsigned long groups = nladdr->nl_groups; bool bound; if (addr_len < sizeof(struct sockaddr_nl)) @@ -1011,9 +1011,7 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr, return err; } - if (nlk->ngroups == 0) - groups = 0; - else if (nlk->ngroups < 8*sizeof(groups)) + if (nlk->ngroups < BITS_PER_LONG) groups &= (1UL << nlk->ngroups) - 1; bound = nlk->bound; |