From: Jason A. Donenfeld Date: Wed, 21 Feb 2018 03:41:59 +0000 (+0100) Subject: netlink: put module reference if dump start fails X-Git-Tag: v4.19~1526^2~13 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b87b6194be631c94785fe93398651e804ed43e28;p=platform%2Fkernel%2Flinux-rpi3.git netlink: put module reference if dump start fails Before, if cb->start() failed, the module reference would never be put, because cb->cb_running is intentionally false at this point. Users are generally annoyed by this because they can no longer unload modules that leak references. Also, it may be possible to tediously wrap a reference counter back to zero, especially since module.c still uses atomic_inc instead of refcount_inc. This patch expands the error path to simply call module_put if cb->start() fails. Fixes: 41c87425a1ac ("netlink: do not set cb_running if dump's start() errs") Signed-off-by: Jason A. Donenfeld Signed-off-by: David S. Miller --- diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 2ad445c..07e8478 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -2308,7 +2308,7 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb, if (cb->start) { ret = cb->start(cb); if (ret) - goto error_unlock; + goto error_put; } nlk->cb_running = true; @@ -2328,6 +2328,8 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb, */ return -EINTR; +error_put: + module_put(control->module); error_unlock: sock_put(sk); mutex_unlock(nlk->cb_mutex);