geneve: fix geneve_config leak on register_netdevice() failure

When geneve_configure() allocates a new geneve_config structure via
geneve_config_alloc() and assigns it to geneve->cfg before calling
register_netdevice(), if register_netdevice() fails early (for example,
in dev_get_valid_name() due to an invalid or duplicate interface name),
register_netdevice() exits without calling dev->priv_destructor.

The caller (e.g. rtnl_newlink()) subsequently calls free_netdev(), which
frees the net_device structure directly via kvfree() because reg_state is
NETREG_UNINITIALIZED, bypassing dev->priv_destructor (geneve_free_dev()).
As a result, the newly allocated geneve_config and its per-CPU dst_cache
are leaked.

Fix this by invoking geneve_free_dev(dev) directly on the error path of
register_netdevice(). Since geneve_free_dev() sets geneve->cfg to NULL,
this call is fully idempotent and safe even if register_netdevice()
failed on a later error path that already ran dev->priv_destructor.

Fixes: 0ba269933f73 ("geneve: convert config to RCU-protected pointer")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260721163950.1483019-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

0 files changed, 0 insertions, 0 deletions