| Message ID | 20241104132434.3101812-1-zilinguan811@gmail.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | ipv6: Use local variable for ifa->flags in inet6_fill_ifaddr | expand |
On Mon, Nov 4, 2024 at 2:25 PM Zilin Guan <zilinguan811@gmail.com> wrote: > > Currently, the inet6_fill_ifaddr() function reads the value of ifa->flags > using READ_ONCE() and stores it in the local variable flags. However, > the subsequent call to put_ifaddrmsg() uses ifa->flags again instead of > the already read local variable. This re-read is unnecessary because > no other thread can modify ifa->flags between the initial READ_ONCE() > and the subsequent use in put_ifaddrmsg(). I do not think this last sentence is true. I would rephrase this or remove it. Otherwise, patch looks fine to me, thanks. > > Signed-off-by: Zilin Guan <zilinguan811@gmail.com> > --- > net/ipv6/addrconf.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c > index 94dceac52884..c4b080471b39 100644 > --- a/net/ipv6/addrconf.c > +++ b/net/ipv6/addrconf.c > @@ -5143,7 +5143,7 @@ static int inet6_fill_ifaddr(struct sk_buff *skb, > return -EMSGSIZE; > > flags = READ_ONCE(ifa->flags); > - put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope), > + put_ifaddrmsg(nlh, ifa->prefix_len, flags, rt_scope(ifa->scope), > ifa->idev->dev->ifindex); > > if (args->netnsid >= 0 && > -- > 2.34.1 >
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 94dceac52884..c4b080471b39 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -5143,7 +5143,7 @@ static int inet6_fill_ifaddr(struct sk_buff *skb, return -EMSGSIZE; flags = READ_ONCE(ifa->flags); - put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope), + put_ifaddrmsg(nlh, ifa->prefix_len, flags, rt_scope(ifa->scope), ifa->idev->dev->ifindex); if (args->netnsid >= 0 &&
Currently, the inet6_fill_ifaddr() function reads the value of ifa->flags using READ_ONCE() and stores it in the local variable flags. However, the subsequent call to put_ifaddrmsg() uses ifa->flags again instead of the already read local variable. This re-read is unnecessary because no other thread can modify ifa->flags between the initial READ_ONCE() and the subsequent use in put_ifaddrmsg(). Signed-off-by: Zilin Guan <zilinguan811@gmail.com> --- net/ipv6/addrconf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)