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| author | Eric Dumazet <edumazet@google.com> | 2024-02-14 08:48:29 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-02-17 16:20:41 +0100 |
| commit | 5c0941c55e5f681ffb05f395222ac673460bb3d0 (patch) | |
| tree | 7ceaf5096a64d55274509ddaa68ca00c1a88466a /lib/kobject_uevent.c | |
| parent | 2444a80c1cc2c4240f60f2162abef3797c1803de (diff) | |
kobject: reduce uevent_sock_mutex scope
This is a followup of commit a3498436b3a0 ("netns: restrict uevents")
- uevent_sock_mutex no longer protects uevent_seqnum thanks
to prior patch in the series.
- uevent_net_broadcast() can run without holding uevent_sock_mutex.
- Instead of grabbing uevent_sock_mutex before calling
kobject_uevent_net_broadcast(), we can move the
mutex_lock(&uevent_sock_mutex) to the place we iterate over
uevent_sock_list : uevent_net_broadcast_untagged().
After this patch, typical netdevice creations and destructions
calling uevent_net_broadcast_tagged() no longer need to acquire
uevent_sock_mutex.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christian Brauner <brauner@kernel.org>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20240214084829.684541-3-edumazet@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'lib/kobject_uevent.c')
| -rw-r--r-- | lib/kobject_uevent.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c index 9cb1a7fdaeba..03b427e2707e 100644 --- a/lib/kobject_uevent.c +++ b/lib/kobject_uevent.c @@ -42,10 +42,9 @@ struct uevent_sock { #ifdef CONFIG_NET static LIST_HEAD(uevent_sock_list); -#endif - /* This lock protects uevent_sock_list */ static DEFINE_MUTEX(uevent_sock_mutex); +#endif /* the strings here must match the enum in include/linux/kobject.h */ static const char *kobject_actions[] = { @@ -315,6 +314,7 @@ static int uevent_net_broadcast_untagged(struct kobj_uevent_env *env, int retval = 0; /* send netlink message */ + mutex_lock(&uevent_sock_mutex); list_for_each_entry(ue_sk, &uevent_sock_list, list) { struct sock *uevent_sock = ue_sk->sk; @@ -334,6 +334,7 @@ static int uevent_net_broadcast_untagged(struct kobj_uevent_env *env, if (retval == -ENOBUFS || retval == -ESRCH) retval = 0; } + mutex_unlock(&uevent_sock_mutex); consume_skb(skb); return retval; @@ -589,10 +590,8 @@ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, if (retval) goto exit; - mutex_lock(&uevent_sock_mutex); retval = kobject_uevent_net_broadcast(kobj, env, action_string, devpath); - mutex_unlock(&uevent_sock_mutex); #ifdef CONFIG_UEVENT_HELPER /* call uevent_helper, usually only enabled during early boot */ @@ -743,9 +742,7 @@ static int uevent_net_rcv_skb(struct sk_buff *skb, struct nlmsghdr *nlh, return -EPERM; } - mutex_lock(&uevent_sock_mutex); ret = uevent_net_broadcast(net->uevent_sock->sk, skb, extack); - mutex_unlock(&uevent_sock_mutex); return ret; } |