ax25: fix reference count leaks of ax25_dev

commit 87563a043cef044fed5db7967a75741cc16ad2b1 upstream.

The previous commit d01ffb9eee4a ("ax25: add refcount in ax25_dev
to avoid UAF bugs") introduces refcount into ax25_dev, but there
are reference leak paths in ax25_ctl_ioctl(), ax25_fwd_ioctl(),
ax25_rt_add(), ax25_rt_del() and ax25_rt_opt().

This patch uses ax25_dev_put() and adjusts the position of
ax25_addr_ax25dev() to fix reference cout leaks of ax25_dev.

Fixes: d01ffb9eee4a ("ax25: add refcount in ax25_dev to avoid UAF bugs")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20220203150811.42256-1-duoming@zju.edu.cn


Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[OP: backport to 4.19: adjust context]
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>