Jakub Kicinski wrote:
The NAPI IDs were not fully exposed to user space prior to the netlink API, so they were never namespaced. The netlink API must ensure that at the very least NAPI instance belongs to the same netns as the owner of the genl sock.
napi_by_id() can become static now, but it needs to move because of dev_get_by_napi_id().
Cc: stable@vger.kernel.org Fixes: 1287c1ae0fc2 ("netdev-genl: Support setting per-NAPI config values") Fixes: 27f91aaf49b3 ("netdev-genl: Add netlink framework functions for napi") Signed-off-by: Jakub Kicinski kuba@kernel.org
Splitting this into fix per-version is a bit tricky, because we need to replace the napi_by_id() helper with a better one. I'll send the stable versions manually.
CC: jdamato@fastly.com CC: almasrymina@google.com CC: amritha.nambiar@intel.com CC: sridhar.samudrala@intel.com
net/core/dev.c | 43 +++++++++++++++++++++++++++++------------- net/core/dev.h | 3 ++- net/core/netdev-genl.c | 6 ++---- 3 files changed, 34 insertions(+), 18 deletions(-)
diff --git a/net/core/dev.c b/net/core/dev.c index 7c63d97b13c1..e001df4cb486 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -753,6 +753,36 @@ int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr, } EXPORT_SYMBOL_GPL(dev_fill_forward_path); +/* must be called under rcu_read_lock(), as we dont take a reference */ +static struct napi_struct *napi_by_id(unsigned int napi_id) +{
- unsigned int hash = napi_id % HASH_SIZE(napi_hash);
- struct napi_struct *napi;
- hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
if (napi->napi_id == napi_id)return napi;- return NULL;
+}
+/* must be called under rcu_read_lock(), as we dont take a reference */
Instead of function comments, invariant checks in code?
Like in dev_get_by_napi_id:
WARN_ON_ONCE(!rcu_read_lock_held());