2023-03-31 07:53:37

by Sricharan Ramabadhran

[permalink] [raw]
Subject: [PATCH V2] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT

On the remote side, when QRTR socket is removed, af_qrtr will call
qrtr_port_remove() which broadcasts the DEL_CLIENT packet to all neighbours
including local NS. NS upon receiving the DEL_CLIENT packet, will remove
the lookups associated with the node:port and broadcasts the DEL_SERVER
packet.

But on the host side, due to the arrival of the DEL_CLIENT packet, the NS
would've already deleted the server belonging to that port. So when the
remote's NS again broadcasts the DEL_SERVER for that port, it throws below
error message on the host:

"failed while handling packet from 2:-2"

So fix this error by not broadcasting the DEL_SERVER packet when the
DEL_CLIENT packet gets processed."

Fixes: 0c2204a4ad71 ("net: qrtr: Migrate nameservice to kernel from userspace")
Signed-off-by: Sricharan Ramabadhran <[email protected]>
Signed-off-by: Ram Kumar Dharuman <[email protected]>
---
[v2] Fixed comments from Manivannan and Jakub Kicinski
Note: Functionally tested on 5.4 and compile tested on 6.3 TOT

net/qrtr/ns.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
index 722936f..0f25a38 100644
--- a/net/qrtr/ns.c
+++ b/net/qrtr/ns.c
@@ -274,7 +274,7 @@ static struct qrtr_server *server_add(unsigned int service,
return NULL;
}

-static int server_del(struct qrtr_node *node, unsigned int port)
+static int server_del(struct qrtr_node *node, unsigned int port, bool bcast)
{
struct qrtr_lookup *lookup;
struct qrtr_server *srv;
@@ -287,7 +287,7 @@ static int server_del(struct qrtr_node *node, unsigned int port)
radix_tree_delete(&node->servers, port);

/* Broadcast the removal of local servers */
- if (srv->node == qrtr_ns.local_node)
+ if (srv->node == qrtr_ns.local_node && bcast)
service_announce_del(&qrtr_ns.bcast_sq, srv);

/* Announce the service's disappearance to observers */
@@ -373,7 +373,7 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from)
}
slot = radix_tree_iter_resume(slot, &iter);
rcu_read_unlock();
- server_del(node, srv->port);
+ server_del(node, srv->port, true);
rcu_read_lock();
}
rcu_read_unlock();
@@ -459,10 +459,13 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from,
kfree(lookup);
}

- /* Remove the server belonging to this port */
+ /* Remove the server belonging to this port but don't broadcast
+ * DEL_SERVER. Neighbours would've already removed the server belonging
+ * to this port due to the DEL_CLIENT broadcast from qrtr_port_remove().
+ */
node = node_get(node_id);
if (node)
- server_del(node, port);
+ server_del(node, port, false);

/* Advertise the removal of this client to all local servers */
local_node = node_get(qrtr_ns.local_node);
@@ -567,7 +570,7 @@ static int ctrl_cmd_del_server(struct sockaddr_qrtr *from,
if (!node)
return -ENOENT;

- return server_del(node, port);
+ return server_del(node, port, true);
}

static int ctrl_cmd_new_lookup(struct sockaddr_qrtr *from,
--
2.7.4


2023-03-31 08:09:18

by Manivannan Sadhasivam

[permalink] [raw]
Subject: Re: [PATCH V2] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT

On Fri, Mar 31, 2023 at 01:18:57PM +0530, Sricharan Ramabadhran wrote:
> On the remote side, when QRTR socket is removed, af_qrtr will call
> qrtr_port_remove() which broadcasts the DEL_CLIENT packet to all neighbours
> including local NS. NS upon receiving the DEL_CLIENT packet, will remove
> the lookups associated with the node:port and broadcasts the DEL_SERVER
> packet.
>
> But on the host side, due to the arrival of the DEL_CLIENT packet, the NS
> would've already deleted the server belonging to that port. So when the
> remote's NS again broadcasts the DEL_SERVER for that port, it throws below
> error message on the host:
>
> "failed while handling packet from 2:-2"
>
> So fix this error by not broadcasting the DEL_SERVER packet when the
> DEL_CLIENT packet gets processed."
>
> Fixes: 0c2204a4ad71 ("net: qrtr: Migrate nameservice to kernel from userspace")
> Signed-off-by: Sricharan Ramabadhran <[email protected]>
> Signed-off-by: Ram Kumar Dharuman <[email protected]>
> ---
> [v2] Fixed comments from Manivannan and Jakub Kicinski
> Note: Functionally tested on 5.4 and compile tested on 6.3 TOT
>
> net/qrtr/ns.c | 15 +++++++++------
> 1 file changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
> index 722936f..0f25a38 100644
> --- a/net/qrtr/ns.c
> +++ b/net/qrtr/ns.c
> @@ -274,7 +274,7 @@ static struct qrtr_server *server_add(unsigned int service,
> return NULL;
> }
>
> -static int server_del(struct qrtr_node *node, unsigned int port)
> +static int server_del(struct qrtr_node *node, unsigned int port, bool bcast)
> {
> struct qrtr_lookup *lookup;
> struct qrtr_server *srv;
> @@ -287,7 +287,7 @@ static int server_del(struct qrtr_node *node, unsigned int port)
> radix_tree_delete(&node->servers, port);
>
> /* Broadcast the removal of local servers */
> - if (srv->node == qrtr_ns.local_node)
> + if (srv->node == qrtr_ns.local_node && bcast)
> service_announce_del(&qrtr_ns.bcast_sq, srv);
>
> /* Announce the service's disappearance to observers */
> @@ -373,7 +373,7 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from)
> }
> slot = radix_tree_iter_resume(slot, &iter);
> rcu_read_unlock();
> - server_del(node, srv->port);
> + server_del(node, srv->port, true);
> rcu_read_lock();
> }
> rcu_read_unlock();
> @@ -459,10 +459,13 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from,
> kfree(lookup);
> }
>
> - /* Remove the server belonging to this port */
> + /* Remove the server belonging to this port but don't broadcast

This is still not as per the multi line comment style perferred in kernel.
Please read: https://www.kernel.org/doc/html/latest/process/coding-style.html#commenting

- Mani

> + * DEL_SERVER. Neighbours would've already removed the server belonging
> + * to this port due to the DEL_CLIENT broadcast from qrtr_port_remove().
> + */
> node = node_get(node_id);
> if (node)
> - server_del(node, port);
> + server_del(node, port, false);
>
> /* Advertise the removal of this client to all local servers */
> local_node = node_get(qrtr_ns.local_node);
> @@ -567,7 +570,7 @@ static int ctrl_cmd_del_server(struct sockaddr_qrtr *from,
> if (!node)
> return -ENOENT;
>
> - return server_del(node, port);
> + return server_del(node, port, true);
> }
>
> static int ctrl_cmd_new_lookup(struct sockaddr_qrtr *from,
> --
> 2.7.4
>

--
மணிவண்ணன் சதாசிவம்

2023-03-31 08:35:40

by Sricharan Ramabadhran

[permalink] [raw]
Subject: Re: [PATCH V2] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT

<..>

>>
>> -static int server_del(struct qrtr_node *node, unsigned int port)
>> +static int server_del(struct qrtr_node *node, unsigned int port, bool bcast)
>> {
>> struct qrtr_lookup *lookup;
>> struct qrtr_server *srv;
>> @@ -287,7 +287,7 @@ static int server_del(struct qrtr_node *node, unsigned int port)
>> radix_tree_delete(&node->servers, port);
>>
>> /* Broadcast the removal of local servers */
>> - if (srv->node == qrtr_ns.local_node)
>> + if (srv->node == qrtr_ns.local_node && bcast)
>> service_announce_del(&qrtr_ns.bcast_sq, srv);
>>
>> /* Announce the service's disappearance to observers */
>> @@ -373,7 +373,7 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from)
>> }
>> slot = radix_tree_iter_resume(slot, &iter);
>> rcu_read_unlock();
>> - server_del(node, srv->port);
>> + server_del(node, srv->port, true);
>> rcu_read_lock();
>> }
>> rcu_read_unlock();
>> @@ -459,10 +459,13 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from,
>> kfree(lookup);
>> }
>>
>> - /* Remove the server belonging to this port */
>> + /* Remove the server belonging to this port but don't broadcast
>
> This is still not as per the multi line comment style perferred in kernel.
> Please read: https://www.kernel.org/doc/html/latest/process/coding-style.html#commenting
>

Ho, i had it like first style and checkpatch cribbed. Then changed it
as per the second style for net/ format. You mean we should stick to
1 st style ?

Regards,
Sricharan

2023-03-31 18:39:29

by Manivannan Sadhasivam

[permalink] [raw]
Subject: Re: [PATCH V2] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT

On Fri, Mar 31, 2023 at 02:02:04PM +0530, Sricharan Ramabadhran wrote:
> <..>
>
> > > -static int server_del(struct qrtr_node *node, unsigned int port)
> > > +static int server_del(struct qrtr_node *node, unsigned int port, bool bcast)
> > > {
> > > struct qrtr_lookup *lookup;
> > > struct qrtr_server *srv;
> > > @@ -287,7 +287,7 @@ static int server_del(struct qrtr_node *node, unsigned int port)
> > > radix_tree_delete(&node->servers, port);
> > > /* Broadcast the removal of local servers */
> > > - if (srv->node == qrtr_ns.local_node)
> > > + if (srv->node == qrtr_ns.local_node && bcast)
> > > service_announce_del(&qrtr_ns.bcast_sq, srv);
> > > /* Announce the service's disappearance to observers */
> > > @@ -373,7 +373,7 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from)
> > > }
> > > slot = radix_tree_iter_resume(slot, &iter);
> > > rcu_read_unlock();
> > > - server_del(node, srv->port);
> > > + server_del(node, srv->port, true);
> > > rcu_read_lock();
> > > }
> > > rcu_read_unlock();
> > > @@ -459,10 +459,13 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from,
> > > kfree(lookup);
> > > }
> > > - /* Remove the server belonging to this port */
> > > + /* Remove the server belonging to this port but don't broadcast
> >
> > This is still not as per the multi line comment style perferred in kernel.
> > Please read: https://www.kernel.org/doc/html/latest/process/coding-style.html#commenting
> >
>
> Ho, i had it like first style and checkpatch cribbed. Then changed it
> as per the second style for net/ format. You mean we should stick to
> 1 st style ?
>

Oops, sorry I forgot the fact that the networking code uses a different style.
Ignore my above comment.

- Mani

> Regards,
> Sricharan

--
மணிவண்ணன் சதாசிவம்

2023-03-31 18:39:32

by Manivannan Sadhasivam

[permalink] [raw]
Subject: Re: [PATCH V2] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT

On Fri, Mar 31, 2023 at 01:18:57PM +0530, Sricharan Ramabadhran wrote:
> On the remote side, when QRTR socket is removed, af_qrtr will call
> qrtr_port_remove() which broadcasts the DEL_CLIENT packet to all neighbours
> including local NS. NS upon receiving the DEL_CLIENT packet, will remove
> the lookups associated with the node:port and broadcasts the DEL_SERVER
> packet.
>
> But on the host side, due to the arrival of the DEL_CLIENT packet, the NS
> would've already deleted the server belonging to that port. So when the
> remote's NS again broadcasts the DEL_SERVER for that port, it throws below
> error message on the host:
>
> "failed while handling packet from 2:-2"
>
> So fix this error by not broadcasting the DEL_SERVER packet when the
> DEL_CLIENT packet gets processed."
>
> Fixes: 0c2204a4ad71 ("net: qrtr: Migrate nameservice to kernel from userspace")
> Signed-off-by: Sricharan Ramabadhran <[email protected]>
> Signed-off-by: Ram Kumar Dharuman <[email protected]>

Sender's Signed-off-by should come last. With that fixed,

Reviewed-by: Manivannan Sadhasivam <[email protected]>

- Mani

> ---
> [v2] Fixed comments from Manivannan and Jakub Kicinski
> Note: Functionally tested on 5.4 and compile tested on 6.3 TOT
>
> net/qrtr/ns.c | 15 +++++++++------
> 1 file changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
> index 722936f..0f25a38 100644
> --- a/net/qrtr/ns.c
> +++ b/net/qrtr/ns.c
> @@ -274,7 +274,7 @@ static struct qrtr_server *server_add(unsigned int service,
> return NULL;
> }
>
> -static int server_del(struct qrtr_node *node, unsigned int port)
> +static int server_del(struct qrtr_node *node, unsigned int port, bool bcast)
> {
> struct qrtr_lookup *lookup;
> struct qrtr_server *srv;
> @@ -287,7 +287,7 @@ static int server_del(struct qrtr_node *node, unsigned int port)
> radix_tree_delete(&node->servers, port);
>
> /* Broadcast the removal of local servers */
> - if (srv->node == qrtr_ns.local_node)
> + if (srv->node == qrtr_ns.local_node && bcast)
> service_announce_del(&qrtr_ns.bcast_sq, srv);
>
> /* Announce the service's disappearance to observers */
> @@ -373,7 +373,7 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from)
> }
> slot = radix_tree_iter_resume(slot, &iter);
> rcu_read_unlock();
> - server_del(node, srv->port);
> + server_del(node, srv->port, true);
> rcu_read_lock();
> }
> rcu_read_unlock();
> @@ -459,10 +459,13 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from,
> kfree(lookup);
> }
>
> - /* Remove the server belonging to this port */
> + /* Remove the server belonging to this port but don't broadcast
> + * DEL_SERVER. Neighbours would've already removed the server belonging
> + * to this port due to the DEL_CLIENT broadcast from qrtr_port_remove().
> + */
> node = node_get(node_id);
> if (node)
> - server_del(node, port);
> + server_del(node, port, false);
>
> /* Advertise the removal of this client to all local servers */
> local_node = node_get(qrtr_ns.local_node);
> @@ -567,7 +570,7 @@ static int ctrl_cmd_del_server(struct sockaddr_qrtr *from,
> if (!node)
> return -ENOENT;
>
> - return server_del(node, port);
> + return server_del(node, port, true);
> }
>
> static int ctrl_cmd_new_lookup(struct sockaddr_qrtr *from,
> --
> 2.7.4
>

--
மணிவண்ணன் சதாசிவம்

2023-03-31 19:54:38

by Simon Horman

[permalink] [raw]
Subject: Re: [PATCH V2] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT

On Fri, Mar 31, 2023 at 02:02:04PM +0530, Sricharan Ramabadhran wrote:
> <..>
>
> > > -static int server_del(struct qrtr_node *node, unsigned int port)
> > > +static int server_del(struct qrtr_node *node, unsigned int port, bool bcast)
> > > {
> > > struct qrtr_lookup *lookup;
> > > struct qrtr_server *srv;
> > > @@ -287,7 +287,7 @@ static int server_del(struct qrtr_node *node, unsigned int port)
> > > radix_tree_delete(&node->servers, port);
> > > /* Broadcast the removal of local servers */
> > > - if (srv->node == qrtr_ns.local_node)
> > > + if (srv->node == qrtr_ns.local_node && bcast)
> > > service_announce_del(&qrtr_ns.bcast_sq, srv);
> > > /* Announce the service's disappearance to observers */
> > > @@ -373,7 +373,7 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from)
> > > }
> > > slot = radix_tree_iter_resume(slot, &iter);
> > > rcu_read_unlock();
> > > - server_del(node, srv->port);
> > > + server_del(node, srv->port, true);
> > > rcu_read_lock();
> > > }
> > > rcu_read_unlock();
> > > @@ -459,10 +459,13 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from,
> > > kfree(lookup);
> > > }
> > > - /* Remove the server belonging to this port */
> > > + /* Remove the server belonging to this port but don't broadcast
> >
> > This is still not as per the multi line comment style perferred in kernel.
> > Please read: https://www.kernel.org/doc/html/latest/process/coding-style.html#commenting
> >
>
> Ho, i had it like first style and checkpatch cribbed. Then changed it
> as per the second style for net/ format. You mean we should stick to
> 1 st style ?

I think that what you have matches the preferred style for net/ code,
and thus is correct for this patch.

https://www.kernel.org/doc/html/latest/process/maintainer-netdev.html#multi-line-comments