| Message ID | 20200707171515.110818-1-izabela.bakollari@gmail.com |
|---|---|
| State | Changes Requested |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net-next] dropwatch: Support monitoring of dropped frames | expand |
On 7/7/20 10:15 AM, izabela.bakollari@gmail.com wrote: > From: Izabela Bakollari <izabela.bakollari@gmail.com> > > Dropwatch is a utility that monitors dropped frames by having userspace > record them over the dropwatch protocol over a file. This augument > allows live monitoring of dropped frames using tools like tcpdump. > > With this feature, dropwatch allows two additional commands (start and > stop interface) which allows the assignment of a net_device to the > dropwatch protocol. When assinged, dropwatch will clone dropped frames, > and receive them on the assigned interface, allowing tools like tcpdump > to monitor for them. > > With this feature, create a dummy ethernet interface (ip link add dev > dummy0 type dummy), assign it to the dropwatch kernel subsystem, by using > these new commands, and then monitor dropped frames in real time by > running tcpdump -i dummy0. > > Signed-off-by: Izabela Bakollari <izabela.bakollari@gmail.com> > --- > include/uapi/linux/net_dropmon.h | 3 ++ > net/core/drop_monitor.c | 79 +++++++++++++++++++++++++++++++- > 2 files changed, 80 insertions(+), 2 deletions(-) > > diff --git a/include/uapi/linux/net_dropmon.h b/include/uapi/linux/net_dropmon.h > index 67e31f329190..e8e861e03a8a 100644 > --- a/include/uapi/linux/net_dropmon.h > +++ b/include/uapi/linux/net_dropmon.h > @@ -58,6 +58,8 @@ enum { > NET_DM_CMD_CONFIG_NEW, > NET_DM_CMD_STATS_GET, > NET_DM_CMD_STATS_NEW, > + NET_DM_CMD_START_IFC, > + NET_DM_CMD_STOP_IFC, > _NET_DM_CMD_MAX, > }; > > @@ -93,6 +95,7 @@ enum net_dm_attr { > NET_DM_ATTR_SW_DROPS, /* flag */ > NET_DM_ATTR_HW_DROPS, /* flag */ > NET_DM_ATTR_FLOW_ACTION_COOKIE, /* binary */ > + NET_DM_ATTR_IFNAME, /* string */ > > __NET_DM_ATTR_MAX, > NET_DM_ATTR_MAX = __NET_DM_ATTR_MAX - 1 > diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c > index 8e33cec9fc4e..8049bff05abd 100644 > --- a/net/core/drop_monitor.c > +++ b/net/core/drop_monitor.c > @@ -30,6 +30,7 @@ > #include <net/genetlink.h> > #include <net/netevent.h> > #include <net/flow_offload.h> > +#include <net/sock.h> > > #include <trace/events/skb.h> > #include <trace/events/napi.h> > @@ -46,6 +47,7 @@ > */ > static int trace_state = TRACE_OFF; > static bool monitor_hw; > +struct net_device *interface; > > /* net_dm_mutex > * > @@ -220,9 +222,8 @@ static void trace_drop_common(struct sk_buff *skb, void *location) > struct per_cpu_dm_data *data; > unsigned long flags; > > - local_irq_save(flags); > + spin_lock_irqsave(&data->lock, flags); > data = this_cpu_ptr(&dm_cpu_data); > - spin_lock(&data->lock); This change seems unrelated ? And also buggy, since data is essentially garbage when you call spin_lock_irqsave(&data->lock, flags); > dskb = data->skb; > > if (!dskb) > @@ -255,6 +256,12 @@ static void trace_drop_common(struct sk_buff *skb, void *location) > > out: > spin_unlock_irqrestore(&data->lock, flags); > + > + if (interface && interface != skb->dev) { > + skb = skb_clone(skb, GFP_ATOMIC); skb_clone() can return NULL > + skb->dev = interface; > + netif_receive_skb(skb); > + } > } > > static void trace_kfree_skb_hit(void *ignore, struct sk_buff *skb, void *location) > @@ -1315,6 +1322,63 @@ static int net_dm_cmd_trace(struct sk_buff *skb, > return -EOPNOTSUPP; > } > > +static int net_dm_interface_start(struct net *net, const char *ifname) > +{ > + struct net_device *nd; > + > + nd = dev_get_by_name(net, ifname); > + > + if (nd) { > + interface = nd; > + dev_hold(interface); > + } else { > + return -ENODEV; > + } > + return 0; > +} > + What happens after this monitoring is started, then the admin does : rmmod ifb
On 7/7/20 10:33 AM, Eric Dumazet wrote: > > > What happens after this monitoring is started, then the admin does : > > rmmod ifb > I meant : rmmod dummy
On 7/7/20 10:15 AM, izabela.bakollari@gmail.com wrote: > From: Izabela Bakollari <izabela.bakollari@gmail.com> > > Dropwatch is a utility that monitors dropped frames by having userspace > record them over the dropwatch protocol over a file. This augument > allows live monitoring of dropped frames using tools like tcpdump. > > With this feature, dropwatch allows two additional commands (start and > stop interface) which allows the assignment of a net_device to the > dropwatch protocol. When assinged, dropwatch will clone dropped frames, > and receive them on the assigned interface, allowing tools like tcpdump > to monitor for them. > > With this feature, create a dummy ethernet interface (ip link add dev > dummy0 type dummy), assign it to the dropwatch kernel subsystem, by using > these new commands, and then monitor dropped frames in real time by > running tcpdump -i dummy0. > > Signed-off-by: Izabela Bakollari <izabela.bakollari@gmail.com> > --- > include/uapi/linux/net_dropmon.h | 3 ++ > net/core/drop_monitor.c | 79 +++++++++++++++++++++++++++++++- > 2 files changed, 80 insertions(+), 2 deletions(-) > > diff --git a/include/uapi/linux/net_dropmon.h b/include/uapi/linux/net_dropmon.h > index 67e31f329190..e8e861e03a8a 100644 > --- a/include/uapi/linux/net_dropmon.h > +++ b/include/uapi/linux/net_dropmon.h > @@ -58,6 +58,8 @@ enum { > NET_DM_CMD_CONFIG_NEW, > NET_DM_CMD_STATS_GET, > NET_DM_CMD_STATS_NEW, > + NET_DM_CMD_START_IFC, > + NET_DM_CMD_STOP_IFC, > _NET_DM_CMD_MAX, > }; > > @@ -93,6 +95,7 @@ enum net_dm_attr { > NET_DM_ATTR_SW_DROPS, /* flag */ > NET_DM_ATTR_HW_DROPS, /* flag */ > NET_DM_ATTR_FLOW_ACTION_COOKIE, /* binary */ > + NET_DM_ATTR_IFNAME, /* string */ > > __NET_DM_ATTR_MAX, > NET_DM_ATTR_MAX = __NET_DM_ATTR_MAX - 1 > diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c > index 8e33cec9fc4e..8049bff05abd 100644 > --- a/net/core/drop_monitor.c > +++ b/net/core/drop_monitor.c > @@ -30,6 +30,7 @@ > #include <net/genetlink.h> > #include <net/netevent.h> > #include <net/flow_offload.h> > +#include <net/sock.h> > > #include <trace/events/skb.h> > #include <trace/events/napi.h> > @@ -46,6 +47,7 @@ > */ > static int trace_state = TRACE_OFF; > static bool monitor_hw; > +struct net_device *interface; > > /* net_dm_mutex > * > @@ -220,9 +222,8 @@ static void trace_drop_common(struct sk_buff *skb, void *location) > struct per_cpu_dm_data *data; > unsigned long flags; > > - local_irq_save(flags); > + spin_lock_irqsave(&data->lock, flags); > data = this_cpu_ptr(&dm_cpu_data); > - spin_lock(&data->lock); > dskb = data->skb; > > if (!dskb) > @@ -255,6 +256,12 @@ static void trace_drop_common(struct sk_buff *skb, void *location) > > out: > spin_unlock_irqrestore(&data->lock, flags); > + What protects interface from being changed under us by another thread/cpu ? > + if (interface && interface != skb->dev) { > + skb = skb_clone(skb, GFP_ATOMIC); > + skb->dev = interface; > + netif_receive_skb(skb); > + } > } > > static void trace_kfree_skb_hit(void *ignore, struct sk_buff *skb, void *location) > @@ -1315,6 +1322,63 @@ static int net_dm_cmd_trace(struct sk_buff *skb, > return -EOPNOTSUPP; > } > > +static int net_dm_interface_start(struct net *net, const char *ifname) > +{ > + struct net_device *nd; > + > + nd = dev_get_by_name(net, ifname); > + > + if (nd) { > + interface = nd; If interface was already set, you forgot to dev_put() it. > + dev_hold(interface); Note that dev_get_by_name() already did a dev_hold() > + } else { > + return -ENODEV; > + } > + return 0; > +} > + > +static int net_dm_interface_stop(struct net *net, const char *ifname) > +{ > + struct net_device *nd; > + > + nd = dev_get_by_name(net, ifname); > + > + if (nd) { > + interface = nd; You probably meant : interface = NULL; ? > + dev_put(interface); and dev_put(nd); > + } else { > + return -ENODEV; > + } > + return 0; > +} > + > +static int net_dm_cmd_ifc_trace(struct sk_buff *skb, struct genl_info *info) > +{ > + struct net *net = sock_net(skb->sk); > + char ifname[IFNAMSIZ]; > + int rc; > + > + memset(ifname, 0, IFNAMSIZ); > + nla_strlcpy(ifname, info->attrs[NET_DM_ATTR_IFNAME], IFNAMSIZ - 1); > + > + switch (info->genlhdr->cmd) { > + case NET_DM_CMD_START_IFC: > + rc = net_dm_interface_start(net, ifname); > + if (rc) > + return rc; > + break; > + case NET_DM_CMD_STOP_IFC: > + if (interface) { > + rc = net_dm_interface_stop(net, interface->ifname); > + return rc; > + } else { > + return -ENODEV; > + } > + } > + > + return 0; > +} > + > static int net_dm_config_fill(struct sk_buff *msg, struct genl_info *info) > { > void *hdr; > @@ -1543,6 +1607,7 @@ static const struct nla_policy net_dm_nl_policy[NET_DM_ATTR_MAX + 1] = { > [NET_DM_ATTR_QUEUE_LEN] = { .type = NLA_U32 }, > [NET_DM_ATTR_SW_DROPS] = {. type = NLA_FLAG }, > [NET_DM_ATTR_HW_DROPS] = {. type = NLA_FLAG }, > + [NET_DM_ATTR_IFNAME] = {. type = NLA_STRING, .len = IFNAMSIZ }, > }; > > static const struct genl_ops dropmon_ops[] = { > @@ -1570,6 +1635,16 @@ static const struct genl_ops dropmon_ops[] = { > .cmd = NET_DM_CMD_STATS_GET, > .doit = net_dm_cmd_stats_get, > }, > + { > + .cmd = NET_DM_CMD_START_IFC, > + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, > + .doit = net_dm_cmd_ifc_trace, > + }, > + { > + .cmd = NET_DM_CMD_STOP_IFC, > + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, > + .doit = net_dm_cmd_ifc_trace, > + }, > }; > > static int net_dm_nl_pre_doit(const struct genl_ops *ops, >
Hi,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on net-next/master]
url: https://github.com/0day-ci/linux/commits/izabela-bakollari-gmail-com/dropwatch-Support-monitoring-of-dropped-frames/20200708-011806
base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git d47a72152097d7be7cfc453d205196c0aa976c33
config: i386-allyesconfig (attached as .config)
compiler: gcc-9 (Debian 9.3.0-14) 9.3.0
reproduce (this is a W=1 build):
# save the attached .config to linux build tree
make W=1 ARCH=i386
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
net/core/drop_monitor.c: In function 'net_dm_cmd_ifc_trace':
>> net/core/drop_monitor.c:1375:47: error: 'struct net_device' has no member named 'ifname'; did you mean 'name'?
1375 | rc = net_dm_interface_stop(net, interface->ifname);
| ^~~~~~
| name
vim +1375 net/core/drop_monitor.c
1357
1358 static int net_dm_cmd_ifc_trace(struct sk_buff *skb, struct genl_info *info)
1359 {
1360 struct net *net = sock_net(skb->sk);
1361 char ifname[IFNAMSIZ];
1362 int rc;
1363
1364 memset(ifname, 0, IFNAMSIZ);
1365 nla_strlcpy(ifname, info->attrs[NET_DM_ATTR_IFNAME], IFNAMSIZ - 1);
1366
1367 switch (info->genlhdr->cmd) {
1368 case NET_DM_CMD_START_IFC:
1369 rc = net_dm_interface_start(net, ifname);
1370 if (rc)
1371 return rc;
1372 break;
1373 case NET_DM_CMD_STOP_IFC:
1374 if (interface) {
> 1375 rc = net_dm_interface_stop(net, interface->ifname);
1376 return rc;
1377 } else {
1378 return -ENODEV;
1379 }
1380 }
1381
1382 return 0;
1383 }
1384
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Hi,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on net-next/master]
url: https://github.com/0day-ci/linux/commits/izabela-bakollari-gmail-com/dropwatch-Support-monitoring-of-dropped-frames/20200708-011806
base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git d47a72152097d7be7cfc453d205196c0aa976c33
config: x86_64-allyesconfig (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 02946de3802d3bc65bc9f2eb9b8d4969b5a7add8)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install x86_64 cross compiling tool for clang build
# apt-get install binutils-x86-64-linux-gnu
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All error/warnings (new ones prefixed by >>):
>> net/core/drop_monitor.c:226:21: warning: variable 'data' is uninitialized when used here [-Wuninitialized]
spin_lock_irqsave(&data->lock, flags);
^~~~
include/linux/spinlock.h:383:39: note: expanded from macro 'spin_lock_irqsave'
raw_spin_lock_irqsave(spinlock_check(lock), flags); \
^~~~
include/linux/spinlock.h:251:34: note: expanded from macro 'raw_spin_lock_irqsave'
flags = _raw_spin_lock_irqsave(lock); \
^~~~
net/core/drop_monitor.c:223:30: note: initialize the variable 'data' to silence this warning
struct per_cpu_dm_data *data;
^
= NULL
>> net/core/drop_monitor.c:1375:47: error: no member named 'ifname' in 'struct net_device'; did you mean 'name'?
rc = net_dm_interface_stop(net, interface->ifname);
^~~~~~
name
include/linux/netdevice.h:1844:9: note: 'name' declared here
char name[IFNAMSIZ];
^
1 warning and 1 error generated.
vim +1375 net/core/drop_monitor.c
1357
1358 static int net_dm_cmd_ifc_trace(struct sk_buff *skb, struct genl_info *info)
1359 {
1360 struct net *net = sock_net(skb->sk);
1361 char ifname[IFNAMSIZ];
1362 int rc;
1363
1364 memset(ifname, 0, IFNAMSIZ);
1365 nla_strlcpy(ifname, info->attrs[NET_DM_ATTR_IFNAME], IFNAMSIZ - 1);
1366
1367 switch (info->genlhdr->cmd) {
1368 case NET_DM_CMD_START_IFC:
1369 rc = net_dm_interface_start(net, ifname);
1370 if (rc)
1371 return rc;
1372 break;
1373 case NET_DM_CMD_STOP_IFC:
1374 if (interface) {
> 1375 rc = net_dm_interface_stop(net, interface->ifname);
1376 return rc;
1377 } else {
1378 return -ENODEV;
1379 }
1380 }
1381
1382 return 0;
1383 }
1384
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Hi Eric, Thank you for reviewing my patch. I understand your comments and will be working on correcting what you pointed out. Best, Izabela On Tue, Jul 7, 2020 at 7:52 PM Eric Dumazet <eric.dumazet@gmail.com> wrote: > > > > On 7/7/20 10:15 AM, izabela.bakollari@gmail.com wrote: > > From: Izabela Bakollari <izabela.bakollari@gmail.com> > > > > Dropwatch is a utility that monitors dropped frames by having userspace > > record them over the dropwatch protocol over a file. This augument > > allows live monitoring of dropped frames using tools like tcpdump. > > > > With this feature, dropwatch allows two additional commands (start and > > stop interface) which allows the assignment of a net_device to the > > dropwatch protocol. When assinged, dropwatch will clone dropped frames, > > and receive them on the assigned interface, allowing tools like tcpdump > > to monitor for them. > > > > With this feature, create a dummy ethernet interface (ip link add dev > > dummy0 type dummy), assign it to the dropwatch kernel subsystem, by using > > these new commands, and then monitor dropped frames in real time by > > running tcpdump -i dummy0. > > > > Signed-off-by: Izabela Bakollari <izabela.bakollari@gmail.com> > > --- > > include/uapi/linux/net_dropmon.h | 3 ++ > > net/core/drop_monitor.c | 79 +++++++++++++++++++++++++++++++- > > 2 files changed, 80 insertions(+), 2 deletions(-) > > > > diff --git a/include/uapi/linux/net_dropmon.h b/include/uapi/linux/net_dropmon.h > > index 67e31f329190..e8e861e03a8a 100644 > > --- a/include/uapi/linux/net_dropmon.h > > +++ b/include/uapi/linux/net_dropmon.h > > @@ -58,6 +58,8 @@ enum { > > NET_DM_CMD_CONFIG_NEW, > > NET_DM_CMD_STATS_GET, > > NET_DM_CMD_STATS_NEW, > > + NET_DM_CMD_START_IFC, > > + NET_DM_CMD_STOP_IFC, > > _NET_DM_CMD_MAX, > > }; > > > > @@ -93,6 +95,7 @@ enum net_dm_attr { > > NET_DM_ATTR_SW_DROPS, /* flag */ > > NET_DM_ATTR_HW_DROPS, /* flag */ > > NET_DM_ATTR_FLOW_ACTION_COOKIE, /* binary */ > > + NET_DM_ATTR_IFNAME, /* string */ > > > > __NET_DM_ATTR_MAX, > > NET_DM_ATTR_MAX = __NET_DM_ATTR_MAX - 1 > > diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c > > index 8e33cec9fc4e..8049bff05abd 100644 > > --- a/net/core/drop_monitor.c > > +++ b/net/core/drop_monitor.c > > @@ -30,6 +30,7 @@ > > #include <net/genetlink.h> > > #include <net/netevent.h> > > #include <net/flow_offload.h> > > +#include <net/sock.h> > > > > #include <trace/events/skb.h> > > #include <trace/events/napi.h> > > @@ -46,6 +47,7 @@ > > */ > > static int trace_state = TRACE_OFF; > > static bool monitor_hw; > > +struct net_device *interface; > > > > /* net_dm_mutex > > * > > @@ -220,9 +222,8 @@ static void trace_drop_common(struct sk_buff *skb, void *location) > > struct per_cpu_dm_data *data; > > unsigned long flags; > > > > - local_irq_save(flags); > > + spin_lock_irqsave(&data->lock, flags); > > data = this_cpu_ptr(&dm_cpu_data); > > - spin_lock(&data->lock); > > dskb = data->skb; > > > > if (!dskb) > > @@ -255,6 +256,12 @@ static void trace_drop_common(struct sk_buff *skb, void *location) > > > > out: > > spin_unlock_irqrestore(&data->lock, flags); > > + > > What protects interface from being changed under us by another thread/cpu ? > > > + if (interface && interface != skb->dev) { > > + skb = skb_clone(skb, GFP_ATOMIC); > > + skb->dev = interface; > > + netif_receive_skb(skb); > > + } > > } > > > > static void trace_kfree_skb_hit(void *ignore, struct sk_buff *skb, void *location) > > @@ -1315,6 +1322,63 @@ static int net_dm_cmd_trace(struct sk_buff *skb, > > return -EOPNOTSUPP; > > } > > > > +static int net_dm_interface_start(struct net *net, const char *ifname) > > +{ > > + struct net_device *nd; > > + > > + nd = dev_get_by_name(net, ifname); > > + > > + if (nd) { > > + interface = nd; > > If interface was already set, you forgot to dev_put() it. > > > + dev_hold(interface); > > Note that dev_get_by_name() already did a dev_hold() > > > + } else { > > + return -ENODEV; > > + } > > + return 0; > > +} > > + > > +static int net_dm_interface_stop(struct net *net, const char *ifname) > > +{ > > + struct net_device *nd; > > + > > + nd = dev_get_by_name(net, ifname); > > + > > + if (nd) { > > > > > + interface = nd; > > > You probably meant : interface = NULL; ? > > > + dev_put(interface); > > and dev_put(nd); > > > > + } else { > > + return -ENODEV; > > + } > > + return 0; > > +} > > + > > +static int net_dm_cmd_ifc_trace(struct sk_buff *skb, struct genl_info *info) > > +{ > > + struct net *net = sock_net(skb->sk); > > + char ifname[IFNAMSIZ]; > > + int rc; > > + > > + memset(ifname, 0, IFNAMSIZ); > > + nla_strlcpy(ifname, info->attrs[NET_DM_ATTR_IFNAME], IFNAMSIZ - 1); > > + > > + switch (info->genlhdr->cmd) { > > + case NET_DM_CMD_START_IFC: > > + rc = net_dm_interface_start(net, ifname); > > + if (rc) > > + return rc; > > + break; > > + case NET_DM_CMD_STOP_IFC: > > + if (interface) { > > + rc = net_dm_interface_stop(net, interface->ifname); > > + return rc; > > + } else { > > + return -ENODEV; > > + } > > + } > > + > > + return 0; > > +} > > + > > static int net_dm_config_fill(struct sk_buff *msg, struct genl_info *info) > > { > > void *hdr; > > @@ -1543,6 +1607,7 @@ static const struct nla_policy net_dm_nl_policy[NET_DM_ATTR_MAX + 1] = { > > [NET_DM_ATTR_QUEUE_LEN] = { .type = NLA_U32 }, > > [NET_DM_ATTR_SW_DROPS] = {. type = NLA_FLAG }, > > [NET_DM_ATTR_HW_DROPS] = {. type = NLA_FLAG }, > > + [NET_DM_ATTR_IFNAME] = {. type = NLA_STRING, .len = IFNAMSIZ }, > > }; > > > > static const struct genl_ops dropmon_ops[] = { > > @@ -1570,6 +1635,16 @@ static const struct genl_ops dropmon_ops[] = { > > .cmd = NET_DM_CMD_STATS_GET, > > .doit = net_dm_cmd_stats_get, > > }, > > + { > > + .cmd = NET_DM_CMD_START_IFC, > > + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, > > + .doit = net_dm_cmd_ifc_trace, > > + }, > > + { > > + .cmd = NET_DM_CMD_STOP_IFC, > > + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, > > + .doit = net_dm_cmd_ifc_trace, > > + }, > > }; > > > > static int net_dm_nl_pre_doit(const struct genl_ops *ops, > >
diff --git a/include/uapi/linux/net_dropmon.h b/include/uapi/linux/net_dropmon.h index 67e31f329190..e8e861e03a8a 100644 --- a/include/uapi/linux/net_dropmon.h +++ b/include/uapi/linux/net_dropmon.h @@ -58,6 +58,8 @@ enum { NET_DM_CMD_CONFIG_NEW, NET_DM_CMD_STATS_GET, NET_DM_CMD_STATS_NEW, + NET_DM_CMD_START_IFC, + NET_DM_CMD_STOP_IFC, _NET_DM_CMD_MAX, }; @@ -93,6 +95,7 @@ enum net_dm_attr { NET_DM_ATTR_SW_DROPS, /* flag */ NET_DM_ATTR_HW_DROPS, /* flag */ NET_DM_ATTR_FLOW_ACTION_COOKIE, /* binary */ + NET_DM_ATTR_IFNAME, /* string */ __NET_DM_ATTR_MAX, NET_DM_ATTR_MAX = __NET_DM_ATTR_MAX - 1 diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c index 8e33cec9fc4e..8049bff05abd 100644 --- a/net/core/drop_monitor.c +++ b/net/core/drop_monitor.c @@ -30,6 +30,7 @@ #include <net/genetlink.h> #include <net/netevent.h> #include <net/flow_offload.h> +#include <net/sock.h> #include <trace/events/skb.h> #include <trace/events/napi.h> @@ -46,6 +47,7 @@ */ static int trace_state = TRACE_OFF; static bool monitor_hw; +struct net_device *interface; /* net_dm_mutex * @@ -220,9 +222,8 @@ static void trace_drop_common(struct sk_buff *skb, void *location) struct per_cpu_dm_data *data; unsigned long flags; - local_irq_save(flags); + spin_lock_irqsave(&data->lock, flags); data = this_cpu_ptr(&dm_cpu_data); - spin_lock(&data->lock); dskb = data->skb; if (!dskb) @@ -255,6 +256,12 @@ static void trace_drop_common(struct sk_buff *skb, void *location) out: spin_unlock_irqrestore(&data->lock, flags); + + if (interface && interface != skb->dev) { + skb = skb_clone(skb, GFP_ATOMIC); + skb->dev = interface; + netif_receive_skb(skb); + } } static void trace_kfree_skb_hit(void *ignore, struct sk_buff *skb, void *location) @@ -1315,6 +1322,63 @@ static int net_dm_cmd_trace(struct sk_buff *skb, return -EOPNOTSUPP; } +static int net_dm_interface_start(struct net *net, const char *ifname) +{ + struct net_device *nd; + + nd = dev_get_by_name(net, ifname); + + if (nd) { + interface = nd; + dev_hold(interface); + } else { + return -ENODEV; + } + return 0; +} + +static int net_dm_interface_stop(struct net *net, const char *ifname) +{ + struct net_device *nd; + + nd = dev_get_by_name(net, ifname); + + if (nd) { + interface = nd; + dev_put(interface); + } else { + return -ENODEV; + } + return 0; +} + +static int net_dm_cmd_ifc_trace(struct sk_buff *skb, struct genl_info *info) +{ + struct net *net = sock_net(skb->sk); + char ifname[IFNAMSIZ]; + int rc; + + memset(ifname, 0, IFNAMSIZ); + nla_strlcpy(ifname, info->attrs[NET_DM_ATTR_IFNAME], IFNAMSIZ - 1); + + switch (info->genlhdr->cmd) { + case NET_DM_CMD_START_IFC: + rc = net_dm_interface_start(net, ifname); + if (rc) + return rc; + break; + case NET_DM_CMD_STOP_IFC: + if (interface) { + rc = net_dm_interface_stop(net, interface->ifname); + return rc; + } else { + return -ENODEV; + } + } + + return 0; +} + static int net_dm_config_fill(struct sk_buff *msg, struct genl_info *info) { void *hdr; @@ -1543,6 +1607,7 @@ static const struct nla_policy net_dm_nl_policy[NET_DM_ATTR_MAX + 1] = { [NET_DM_ATTR_QUEUE_LEN] = { .type = NLA_U32 }, [NET_DM_ATTR_SW_DROPS] = {. type = NLA_FLAG }, [NET_DM_ATTR_HW_DROPS] = {. type = NLA_FLAG }, + [NET_DM_ATTR_IFNAME] = {. type = NLA_STRING, .len = IFNAMSIZ }, }; static const struct genl_ops dropmon_ops[] = { @@ -1570,6 +1635,16 @@ static const struct genl_ops dropmon_ops[] = { .cmd = NET_DM_CMD_STATS_GET, .doit = net_dm_cmd_stats_get, }, + { + .cmd = NET_DM_CMD_START_IFC, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = net_dm_cmd_ifc_trace, + }, + { + .cmd = NET_DM_CMD_STOP_IFC, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = net_dm_cmd_ifc_trace, + }, }; static int net_dm_nl_pre_doit(const struct genl_ops *ops,