kevin/linux
1
Fork 0
Code

devlink: protect devlink->dev by the instance lock

Browse Source 
devlink->dev is assumed to be always valid as long as any
outstanding reference to the devlink instance exists.

In prep for weakening of the references take the instance lock.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jakub Kicinski 2023-01-05 22:33:56 -08:00 committed by David S. Miller
parent 7a54a5195b
commit 870c7ad4a5
3 changed files with 11 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
net/devlink/devl_internal.h
View File

@ -131,7 +131,8 @@ struct devlink_gen_cmd {
extern const struct genl_small_ops devlink_nl_ops[56];
struct devlink *devlink_get_from_attrs(struct net *net, struct nlattr **attrs);
struct devlink *
devlink_get_from_attrs_lock(struct net *net, struct nlattr **attrs);
void devlink_notify_unregister(struct devlink *devlink);
void devlink_notify_register(struct devlink *devlink);

7
net/devlink/leftover.c
View File

@ -6314,12 +6314,10 @@ static int devlink_nl_cmd_region_read_dumpit(struct sk_buff *skb,
start_offset = state->start_offset;
devlink = devlink_get_from_attrs(sock_net(cb->skb->sk), attrs);
devlink = devlink_get_from_attrs_lock(sock_net(cb->skb->sk), attrs);
if (IS_ERR(devlink))
return PTR_ERR(devlink);
devl_lock(devlink);
if (!attrs[DEVLINK_ATTR_REGION_NAME]) {
NL_SET_ERR_MSG(cb->extack, "No region name provided");
err = -EINVAL;
@ -7735,9 +7733,10 @@ devlink_health_reporter_get_from_cb(struct netlink_callback *cb)
struct nlattr **attrs = info->attrs;
struct devlink *devlink;
devlink = devlink_get_from_attrs(sock_net(cb->skb->sk), attrs);
devlink = devlink_get_from_attrs_lock(sock_net(cb->skb->sk), attrs);
if (IS_ERR(devlink))
return NULL;
devl_unlock(devlink);
reporter = devlink_health_reporter_get_from_attrs(devlink, attrs);
devlink_put(devlink);

9
net/devlink/netlink.c
View File

@ -82,7 +82,8 @@ static const struct nla_policy devlink_nl_policy[DEVLINK_ATTR_MAX + 1] = {
[DEVLINK_ATTR_REGION_DIRECT] = { .type = NLA_FLAG },
};
struct devlink *devlink_get_from_attrs(struct net *net, struct nlattr **attrs)
struct devlink *
devlink_get_from_attrs_lock(struct net *net, struct nlattr **attrs)
{
struct devlink *devlink;
unsigned long index;
@ -96,9 +97,11 @@ struct devlink *devlink_get_from_attrs(struct net *net, struct nlattr **attrs)
devname = nla_data(attrs[DEVLINK_ATTR_DEV_NAME]);
devlinks_xa_for_each_registered_get(net, index, devlink) {
devl_lock(devlink);
if (strcmp(devlink->dev->bus->name, busname) == 0 &&
strcmp(dev_name(devlink->dev), devname) == 0)
return devlink;
devl_unlock(devlink);
devlink_put(devlink);
}
@ -113,10 +116,10 @@ static int devlink_nl_pre_doit(const struct genl_split_ops *ops,
struct devlink *devlink;
int err;
devlink = devlink_get_from_attrs(genl_info_net(info), info->attrs);
devlink = devlink_get_from_attrs_lock(genl_info_net(info), info->attrs);
if (IS_ERR(devlink))
return PTR_ERR(devlink);
devl_lock(devlink);
info->user_ptr[0] = devlink;
if (ops->internal_flags & DEVLINK_NL_FLAG_NEED_PORT) {
devlink_port = devlink_port_get_from_info(devlink, info);