diff options
| author | Kuniyuki Iwashima <kuniyu@google.com> | 2025-07-16 22:08:13 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-07-17 16:25:21 -0700 |
| commit | cc03492c7b92cb4414bd72a88f4d88ceb78362f9 (patch) | |
| tree | 1b46db70c93a096173d0d4e1e0ebff603dbdc1cf | |
| parent | d539d8fbd8fcf64a1492c51f5ee99aaa8a8dc9ab (diff) | |
neighbour: Annotate access to struct pneigh_entry.{flags,protocol}.
We will convert pneigh readers to RCU, and its flags and protocol
will be read locklessly.
Let's annotate the access to the two fields.
Note that all access to pn->permanent is under RTNL (neigh_add()
and pneigh_ifdown_and_unlock()), so WRITE_ONCE() and READ_ONCE()
are not needed.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250716221221.442239-9-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/core/neighbour.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/net/core/neighbour.c b/net/core/neighbour.c index fa2e60a479ef..59dfdecddff3 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -2044,10 +2044,10 @@ static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, err = -ENOBUFS; pn = pneigh_create(tbl, net, dst, dev); if (pn) { - pn->flags = ndm_flags; + WRITE_ONCE(pn->flags, ndm_flags); pn->permanent = !!(ndm->ndm_state & NUD_PERMANENT); if (protocol) - pn->protocol = protocol; + WRITE_ONCE(pn->protocol, protocol); err = 0; } goto out; @@ -2678,13 +2678,15 @@ static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn, u32 neigh_flags, neigh_flags_ext; struct nlmsghdr *nlh; struct ndmsg *ndm; + u8 protocol; nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags); if (nlh == NULL) return -EMSGSIZE; - neigh_flags_ext = pn->flags >> NTF_EXT_SHIFT; - neigh_flags = pn->flags & NTF_OLD_MASK; + neigh_flags = READ_ONCE(pn->flags); + neigh_flags_ext = neigh_flags >> NTF_EXT_SHIFT; + neigh_flags &= NTF_OLD_MASK; ndm = nlmsg_data(nlh); ndm->ndm_family = tbl->family; @@ -2698,7 +2700,8 @@ static int pneigh_fill_info(struct sk_buff *skb, struct pneigh_entry *pn, if (nla_put(skb, NDA_DST, tbl->key_len, pn->key)) goto nla_put_failure; - if (pn->protocol && nla_put_u8(skb, NDA_PROTOCOL, pn->protocol)) + protocol = READ_ONCE(pn->protocol); + if (protocol && nla_put_u8(skb, NDA_PROTOCOL, protocol)) goto nla_put_failure; if (neigh_flags_ext && nla_put_u32(skb, NDA_FLAGS_EXT, neigh_flags_ext)) goto nla_put_failure; |