From 2bd470fc08cbbfd4f2e53a620362806620d217ed Mon Sep 17 00:00:00 2001 From: stephen hemminger Date: Wed, 19 Jun 2013 18:06:54 -0700 Subject: netlink: export netlink_diag.h header The netlink_diag.h is in include/uapi/linux but not in the Kbuild necessary to cause it to be exported by make headers_install. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- include/uapi/linux/Kbuild | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/uapi/linux/Kbuild b/include/uapi/linux/Kbuild index ab5d4992e568..bdc6e87ff3eb 100644 --- a/include/uapi/linux/Kbuild +++ b/include/uapi/linux/Kbuild @@ -261,6 +261,7 @@ header-y += net_dropmon.h header-y += net_tstamp.h header-y += netconf.h header-y += netdevice.h +header-y += netlink_diag.h header-y += netfilter.h header-y += netfilter_arp.h header-y += netfilter_bridge.h -- cgit v1.2.3 From a7bf58040f4e8a7245cb3e24ab93057be3c46363 Mon Sep 17 00:00:00 2001 From: Olaf Hering Date: Fri, 14 Jun 2013 17:07:01 +0200 Subject: net: vlan: fix comment for vlan_ethhdr->h_vlan_proto After addition of 8021AD h_vlan_proto can be either ETH_P_8021Q or ETH_P_8021AD. Signed-off-by: Olaf Hering Signed-off-by: David S. Miller --- include/linux/if_vlan.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h index 52bd03b38962..637fa71de0c7 100644 --- a/include/linux/if_vlan.h +++ b/include/linux/if_vlan.h @@ -44,7 +44,7 @@ struct vlan_hdr { * struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr) * @h_dest: destination ethernet address * @h_source: source ethernet address - * @h_vlan_proto: ethernet protocol (always 0x8100) + * @h_vlan_proto: ethernet protocol * @h_vlan_TCI: priority and VLAN ID * @h_vlan_encapsulated_proto: packet type ID or len */ -- cgit v1.2.3 From 21a31013f774c726bd199526cd673acc6432b21d Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 24 Jun 2013 11:22:53 +0200 Subject: ACPI / dock / PCI: Synchronous handling of dock events for PCI devices The interactions between the ACPI dock driver and the ACPI-based PCI hotplug (acpiphp) are currently problematic because of ordering issues during hot-remove operations. First of all, the current ACPI glue code expects that physical devices will always be deleted before deleting the companion ACPI device objects. Otherwise, acpi_unbind_one() will fail with a warning message printed to the kernel log, for example: [ 185.026073] usb usb5: Oops, 'acpi_handle' corrupt [ 185.035150] pci 0000:1b:00.0: Oops, 'acpi_handle' corrupt [ 185.035515] pci 0000:18:02.0: Oops, 'acpi_handle' corrupt [ 180.013656] port1: Oops, 'acpi_handle' corrupt This means, in particular, that struct pci_dev objects have to be deleted before the struct acpi_device objects they are "glued" with. Now, the following happens the during the undocking of an ACPI-based dock station: 1) hotplug_dock_devices() invokes registered hotplug callbacks to destroy physical devices associated with the ACPI device objects depending on the dock station. It calls dd->ops->handler() for each of those device objects. 2) For PCI devices dd->ops->handler() points to handle_hotplug_event_func() that queues up a separate work item to execute _handle_hotplug_event_func() for the given device and returns immediately. That work item will be executed later. 3) hotplug_dock_devices() calls dock_remove_acpi_device() for each device depending on the dock station. This runs acpi_bus_trim() for each of them, which causes the underlying ACPI device object to be destroyed, but the work items queued up by handle_hotplug_event_func() haven't been started yet. 4) _handle_hotplug_event_func() queued up in step 2) are executed and cause the above failure to happen, because the PCI devices they handle do not have the companion ACPI device objects any more (those objects have been deleted in step 3). The possible breakage doesn't end here, though, because hotplug_dock_devices() may return before at least some of the _handle_hotplug_event_func() work items spawned by it have a chance to complete and then undock() will cause _DCK to be evaluated and that will cause the devices handled by the _handle_hotplug_event_func() to go away possibly while they are being accessed. This means that dd->ops->handler() for PCI devices should not point to handle_hotplug_event_func(). Instead, it should point to a function that will do the work of _handle_hotplug_event_func() synchronously. For this reason, introduce such a function, hotplug_event_func(), and modity acpiphp_dock_ops to point to it as the handler. Unfortunately, however, this is not sufficient, because if the dock code were not changed further, hotplug_event_func() would now deadlock with hotplug_dock_devices() that called it, since it would run unregister_hotplug_dock_device() which in turn would attempt to acquire the dock station's hp_lock mutex already acquired by hotplug_dock_devices(). To resolve that deadlock use the observation that unregister_hotplug_dock_device() won't need to acquire hp_lock if PCI bridges the devices on the dock station depend on are prevented from being removed prematurely while the first loop in hotplug_dock_devices() is in progress. To make that possible, introduce a mechanism by which the callers of register_hotplug_dock_device() can provide "init" and "release" routines that will be executed, respectively, during the addition and removal of the physical device object associated with the given ACPI device handle. Make acpiphp use two new functions, acpiphp_dock_init() and acpiphp_dock_release(), that call get_bridge() and put_bridge(), respectively, on the acpiphp bridge holding the given device, for this purpose. In addition to that, remove the dock station's list of "hotplug devices" and make the dock code always walk the whole list of "dependent devices" instead in such a way that the loops in hotplug_dock_devices() and dock_event() (replacing the loops over "hotplug devices") will take references to the list entries that register_hotplug_dock_device() has been called for. That prevents the "release" routines associated with those entries from being called while the given entry is being processed and for PCI devices this means that their bridges won't be removed (by a concurrent thread) while hotplug_event_func() handling them is being executed. This change is based on two earlier patches from Jiang Liu. References: https://bugzilla.kernel.org/show_bug.cgi?id=59501 Reported-and-tested-by: Alexander E. Patrakov Tracked-down-by: Jiang Liu Tested-by: Illya Klymov Signed-off-by: Rafael J. Wysocki Acked-by: Yinghai Lu Cc: 3.9+ --- drivers/acpi/dock.c | 137 +++++++++++++++++++++++++------------ drivers/pci/hotplug/acpiphp_glue.c | 46 +++++++++---- include/acpi/acpi_drivers.h | 8 ++- 3 files changed, 133 insertions(+), 58 deletions(-) (limited to 'include') diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c index c3b34f94382f..14de9f46972e 100644 --- a/drivers/acpi/dock.c +++ b/drivers/acpi/dock.c @@ -66,20 +66,21 @@ struct dock_station { spinlock_t dd_lock; struct mutex hp_lock; struct list_head dependent_devices; - struct list_head hotplug_devices; struct list_head sibling; struct platform_device *dock_device; }; static LIST_HEAD(dock_stations); static int dock_station_count; +static DEFINE_MUTEX(hotplug_lock); struct dock_dependent_device { struct list_head list; - struct list_head hotplug_list; acpi_handle handle; - const struct acpi_dock_ops *ops; - void *context; + const struct acpi_dock_ops *hp_ops; + void *hp_context; + unsigned int hp_refcount; + void (*hp_release)(void *); }; #define DOCK_DOCKING 0x00000001 @@ -111,7 +112,6 @@ add_dock_dependent_device(struct dock_station *ds, acpi_handle handle) dd->handle = handle; INIT_LIST_HEAD(&dd->list); - INIT_LIST_HEAD(&dd->hotplug_list); spin_lock(&ds->dd_lock); list_add_tail(&dd->list, &ds->dependent_devices); @@ -121,35 +121,90 @@ add_dock_dependent_device(struct dock_station *ds, acpi_handle handle) } /** - * dock_add_hotplug_device - associate a hotplug handler with the dock station - * @ds: The dock station - * @dd: The dependent device struct - * - * Add the dependent device to the dock's hotplug device list + * dock_init_hotplug - Initialize a hotplug device on a docking station. + * @dd: Dock-dependent device. + * @ops: Dock operations to attach to the dependent device. + * @context: Data to pass to the @ops callbacks and @release. + * @init: Optional initialization routine to run after setting up context. + * @release: Optional release routine to run on removal. */ -static void -dock_add_hotplug_device(struct dock_station *ds, - struct dock_dependent_device *dd) +static int dock_init_hotplug(struct dock_dependent_device *dd, + const struct acpi_dock_ops *ops, void *context, + void (*init)(void *), void (*release)(void *)) { - mutex_lock(&ds->hp_lock); - list_add_tail(&dd->hotplug_list, &ds->hotplug_devices); - mutex_unlock(&ds->hp_lock); + int ret = 0; + + mutex_lock(&hotplug_lock); + + if (dd->hp_context) { + ret = -EEXIST; + } else { + dd->hp_refcount = 1; + dd->hp_ops = ops; + dd->hp_context = context; + dd->hp_release = release; + } + + if (!WARN_ON(ret) && init) + init(context); + + mutex_unlock(&hotplug_lock); + return ret; } /** - * dock_del_hotplug_device - remove a hotplug handler from the dock station - * @ds: The dock station - * @dd: the dependent device struct + * dock_release_hotplug - Decrement hotplug reference counter of dock device. + * @dd: Dock-dependent device. * - * Delete the dependent device from the dock's hotplug device list + * Decrement the reference counter of @dd and if 0, detach its hotplug + * operations from it, reset its context pointer and run the optional release + * routine if present. */ -static void -dock_del_hotplug_device(struct dock_station *ds, - struct dock_dependent_device *dd) +static void dock_release_hotplug(struct dock_dependent_device *dd) { - mutex_lock(&ds->hp_lock); - list_del(&dd->hotplug_list); - mutex_unlock(&ds->hp_lock); + void (*release)(void *) = NULL; + void *context = NULL; + + mutex_lock(&hotplug_lock); + + if (dd->hp_context && !--dd->hp_refcount) { + dd->hp_ops = NULL; + context = dd->hp_context; + dd->hp_context = NULL; + release = dd->hp_release; + dd->hp_release = NULL; + } + + if (release && context) + release(context); + + mutex_unlock(&hotplug_lock); +} + +static void dock_hotplug_event(struct dock_dependent_device *dd, u32 event, + bool uevent) +{ + acpi_notify_handler cb = NULL; + bool run = false; + + mutex_lock(&hotplug_lock); + + if (dd->hp_context) { + run = true; + dd->hp_refcount++; + if (dd->hp_ops) + cb = uevent ? dd->hp_ops->uevent : dd->hp_ops->handler; + } + + mutex_unlock(&hotplug_lock); + + if (!run) + return; + + if (cb) + cb(dd->handle, event, dd->hp_context); + + dock_release_hotplug(dd); } /** @@ -360,9 +415,8 @@ static void hotplug_dock_devices(struct dock_station *ds, u32 event) /* * First call driver specific hotplug functions */ - list_for_each_entry(dd, &ds->hotplug_devices, hotplug_list) - if (dd->ops && dd->ops->handler) - dd->ops->handler(dd->handle, event, dd->context); + list_for_each_entry(dd, &ds->dependent_devices, list) + dock_hotplug_event(dd, event, false); /* * Now make sure that an acpi_device is created for each @@ -398,9 +452,8 @@ static void dock_event(struct dock_station *ds, u32 event, int num) if (num == DOCK_EVENT) kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp); - list_for_each_entry(dd, &ds->hotplug_devices, hotplug_list) - if (dd->ops && dd->ops->uevent) - dd->ops->uevent(dd->handle, event, dd->context); + list_for_each_entry(dd, &ds->dependent_devices, list) + dock_hotplug_event(dd, event, true); if (num != DOCK_EVENT) kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp); @@ -570,19 +623,24 @@ EXPORT_SYMBOL_GPL(unregister_dock_notifier); * @handle: the handle of the device * @ops: handlers to call after docking * @context: device specific data + * @init: Optional initialization routine to run after registration + * @release: Optional release routine to run on unregistration * * If a driver would like to perform a hotplug operation after a dock * event, they can register an acpi_notifiy_handler to be called by * the dock driver after _DCK is executed. */ -int -register_hotplug_dock_device(acpi_handle handle, const struct acpi_dock_ops *ops, - void *context) +int register_hotplug_dock_device(acpi_handle handle, + const struct acpi_dock_ops *ops, void *context, + void (*init)(void *), void (*release)(void *)) { struct dock_dependent_device *dd; struct dock_station *dock_station; int ret = -EINVAL; + if (WARN_ON(!context)) + return -EINVAL; + if (!dock_station_count) return -ENODEV; @@ -597,12 +655,8 @@ register_hotplug_dock_device(acpi_handle handle, const struct acpi_dock_ops *ops * ops */ dd = find_dock_dependent_device(dock_station, handle); - if (dd) { - dd->ops = ops; - dd->context = context; - dock_add_hotplug_device(dock_station, dd); + if (dd && !dock_init_hotplug(dd, ops, context, init, release)) ret = 0; - } } return ret; @@ -624,7 +678,7 @@ void unregister_hotplug_dock_device(acpi_handle handle) list_for_each_entry(dock_station, &dock_stations, sibling) { dd = find_dock_dependent_device(dock_station, handle); if (dd) - dock_del_hotplug_device(dock_station, dd); + dock_release_hotplug(dd); } } EXPORT_SYMBOL_GPL(unregister_hotplug_dock_device); @@ -953,7 +1007,6 @@ static int __init dock_add(acpi_handle handle) mutex_init(&dock_station->hp_lock); spin_lock_init(&dock_station->dd_lock); INIT_LIST_HEAD(&dock_station->sibling); - INIT_LIST_HEAD(&dock_station->hotplug_devices); ATOMIC_INIT_NOTIFIER_HEAD(&dock_notifier_list); INIT_LIST_HEAD(&dock_station->dependent_devices); diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c index 050b6f9abfd1..59df8575a48c 100644 --- a/drivers/pci/hotplug/acpiphp_glue.c +++ b/drivers/pci/hotplug/acpiphp_glue.c @@ -61,6 +61,7 @@ static DEFINE_MUTEX(bridge_mutex); static void handle_hotplug_event_bridge (acpi_handle, u32, void *); static void acpiphp_sanitize_bus(struct pci_bus *bus); static void acpiphp_set_hpp_values(struct pci_bus *bus); +static void hotplug_event_func(acpi_handle handle, u32 type, void *context); static void handle_hotplug_event_func(acpi_handle handle, u32 type, void *context); static void free_bridge(struct kref *kref); @@ -147,7 +148,7 @@ static int post_dock_fixups(struct notifier_block *nb, unsigned long val, static const struct acpi_dock_ops acpiphp_dock_ops = { - .handler = handle_hotplug_event_func, + .handler = hotplug_event_func, }; /* Check whether the PCI device is managed by native PCIe hotplug driver */ @@ -179,6 +180,20 @@ static bool device_is_managed_by_native_pciehp(struct pci_dev *pdev) return true; } +static void acpiphp_dock_init(void *data) +{ + struct acpiphp_func *func = data; + + get_bridge(func->slot->bridge); +} + +static void acpiphp_dock_release(void *data) +{ + struct acpiphp_func *func = data; + + put_bridge(func->slot->bridge); +} + /* callback routine to register each ACPI PCI slot object */ static acpi_status register_slot(acpi_handle handle, u32 lvl, void *context, void **rv) @@ -298,7 +313,8 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv) */ newfunc->flags &= ~FUNC_HAS_EJ0; if (register_hotplug_dock_device(handle, - &acpiphp_dock_ops, newfunc)) + &acpiphp_dock_ops, newfunc, + acpiphp_dock_init, acpiphp_dock_release)) dbg("failed to register dock device\n"); /* we need to be notified when dock events happen @@ -1068,22 +1084,12 @@ static void handle_hotplug_event_bridge(acpi_handle handle, u32 type, alloc_acpi_hp_work(handle, type, context, _handle_hotplug_event_bridge); } -static void _handle_hotplug_event_func(struct work_struct *work) +static void hotplug_event_func(acpi_handle handle, u32 type, void *context) { - struct acpiphp_func *func; + struct acpiphp_func *func = context; char objname[64]; struct acpi_buffer buffer = { .length = sizeof(objname), .pointer = objname }; - struct acpi_hp_work *hp_work; - acpi_handle handle; - u32 type; - - hp_work = container_of(work, struct acpi_hp_work, work); - handle = hp_work->handle; - type = hp_work->type; - func = (struct acpiphp_func *)hp_work->context; - - acpi_scan_lock_acquire(); acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); @@ -1116,6 +1122,18 @@ static void _handle_hotplug_event_func(struct work_struct *work) warn("notify_handler: unknown event type 0x%x for %s\n", type, objname); break; } +} + +static void _handle_hotplug_event_func(struct work_struct *work) +{ + struct acpi_hp_work *hp_work; + struct acpiphp_func *func; + + hp_work = container_of(work, struct acpi_hp_work, work); + func = hp_work->context; + acpi_scan_lock_acquire(); + + hotplug_event_func(hp_work->handle, hp_work->type, func); acpi_scan_lock_release(); kfree(hp_work); /* allocated in handle_hotplug_event_func */ diff --git a/include/acpi/acpi_drivers.h b/include/acpi/acpi_drivers.h index e6168a24b9f0..b420939f5eb5 100644 --- a/include/acpi/acpi_drivers.h +++ b/include/acpi/acpi_drivers.h @@ -123,7 +123,9 @@ extern int register_dock_notifier(struct notifier_block *nb); extern void unregister_dock_notifier(struct notifier_block *nb); extern int register_hotplug_dock_device(acpi_handle handle, const struct acpi_dock_ops *ops, - void *context); + void *context, + void (*init)(void *), + void (*release)(void *)); extern void unregister_hotplug_dock_device(acpi_handle handle); #else static inline int is_dock_device(acpi_handle handle) @@ -139,7 +141,9 @@ static inline void unregister_dock_notifier(struct notifier_block *nb) } static inline int register_hotplug_dock_device(acpi_handle handle, const struct acpi_dock_ops *ops, - void *context) + void *context, + void (*init)(void *), + void (*release)(void *)) { return -ENODEV; } -- cgit v1.2.3 From bd8a7036c06cf15779b31a5397d4afcb12be81ea Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 24 Jun 2013 06:26:00 -0700 Subject: gre: fix a possible skb leak commit 68c331631143 ("v4 GRE: Add TCP segmentation offload for GRE") added a possible skb leak, because it frees only the head of segment list, in case a skb_linearize() call fails. This patch adds a kfree_skb_list() helper to fix the bug. Signed-off-by: Eric Dumazet Cc: Pravin B Shelar Cc: Daniel Borkmann Signed-off-by: David S. Miller --- include/linux/skbuff.h | 1 + net/core/skbuff.c | 20 ++++++++++++-------- net/ipv4/gre.c | 2 +- 3 files changed, 14 insertions(+), 9 deletions(-) (limited to 'include') diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 9c676eae3968..dec1748cd002 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -627,6 +627,7 @@ static inline struct rtable *skb_rtable(const struct sk_buff *skb) } extern void kfree_skb(struct sk_buff *skb); +extern void kfree_skb_list(struct sk_buff *segs); extern void skb_tx_error(struct sk_buff *skb); extern void consume_skb(struct sk_buff *skb); extern void __kfree_skb(struct sk_buff *skb); diff --git a/net/core/skbuff.c b/net/core/skbuff.c index cfd777bd6bd0..1c1738cc4538 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -483,15 +483,8 @@ EXPORT_SYMBOL(skb_add_rx_frag); static void skb_drop_list(struct sk_buff **listp) { - struct sk_buff *list = *listp; - + kfree_skb_list(*listp); *listp = NULL; - - do { - struct sk_buff *this = list; - list = list->next; - kfree_skb(this); - } while (list); } static inline void skb_drop_fraglist(struct sk_buff *skb) @@ -651,6 +644,17 @@ void kfree_skb(struct sk_buff *skb) } EXPORT_SYMBOL(kfree_skb); +void kfree_skb_list(struct sk_buff *segs) +{ + while (segs) { + struct sk_buff *next = segs->next; + + kfree_skb(segs); + segs = next; + } +} +EXPORT_SYMBOL(kfree_skb_list); + /** * skb_tx_error - report an sk_buff xmit error * @skb: buffer that triggered an error diff --git a/net/ipv4/gre.c b/net/ipv4/gre.c index b2e805af9b87..7856d1651d05 100644 --- a/net/ipv4/gre.c +++ b/net/ipv4/gre.c @@ -178,7 +178,7 @@ static struct sk_buff *gre_gso_segment(struct sk_buff *skb, err = __skb_linearize(skb); if (err) { - kfree_skb(segs); + kfree_skb_list(segs); segs = ERR_PTR(err); goto out; } -- cgit v1.2.3 From 5dbe7c178d3f0a4634f088d9e729f1909b9ddcd1 Mon Sep 17 00:00:00 2001 From: Nicolas Schichan Date: Wed, 26 Jun 2013 17:23:42 +0200 Subject: net: fix kernel deadlock with interface rename and netdev name retrieval. When the kernel (compiled with CONFIG_PREEMPT=n) is performing the rename of a network interface, it can end up waiting for a workqueue to complete. If userland is able to invoke a SIOCGIFNAME ioctl or a SO_BINDTODEVICE getsockopt in between, the kernel will deadlock due to the fact that read_secklock_begin() will spin forever waiting for the writer process (the one doing the interface rename) to update the devnet_rename_seq sequence. This patch fixes the problem by adding a helper (netdev_get_name()) and using it in the code handling the SIOCGIFNAME ioctl and SO_BINDTODEVICE setsockopt. The netdev_get_name() helper uses raw_seqcount_begin() to avoid spinning forever, waiting for devnet_rename_seq->sequence to become even. cond_resched() is used in the contended case, before retrying the access to give the writer process a chance to finish. The use of raw_seqcount_begin() will incur some unneeded work in the reader process in the contended case, but this is better than deadlocking the system. Signed-off-by: Nicolas Schichan Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- include/linux/netdevice.h | 1 + net/core/dev.c | 34 ++++++++++++++++++++++++++++++++++ net/core/dev_ioctl.c | 19 ++++--------------- net/core/sock.c | 17 ++--------------- 4 files changed, 41 insertions(+), 30 deletions(-) (limited to 'include') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 60584b185a0c..96e4c21e15e0 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1695,6 +1695,7 @@ extern int init_dummy_netdev(struct net_device *dev); extern struct net_device *dev_get_by_index(struct net *net, int ifindex); extern struct net_device *__dev_get_by_index(struct net *net, int ifindex); extern struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex); +extern int netdev_get_name(struct net *net, char *name, int ifindex); extern int dev_restart(struct net_device *dev); #ifdef CONFIG_NETPOLL_TRAP extern int netpoll_trap(void); diff --git a/net/core/dev.c b/net/core/dev.c index fc1e289397f5..faebb398fb46 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -791,6 +791,40 @@ struct net_device *dev_get_by_index(struct net *net, int ifindex) } EXPORT_SYMBOL(dev_get_by_index); +/** + * netdev_get_name - get a netdevice name, knowing its ifindex. + * @net: network namespace + * @name: a pointer to the buffer where the name will be stored. + * @ifindex: the ifindex of the interface to get the name from. + * + * The use of raw_seqcount_begin() and cond_resched() before + * retrying is required as we want to give the writers a chance + * to complete when CONFIG_PREEMPT is not set. + */ +int netdev_get_name(struct net *net, char *name, int ifindex) +{ + struct net_device *dev; + unsigned int seq; + +retry: + seq = raw_seqcount_begin(&devnet_rename_seq); + rcu_read_lock(); + dev = dev_get_by_index_rcu(net, ifindex); + if (!dev) { + rcu_read_unlock(); + return -ENODEV; + } + + strcpy(name, dev->name); + rcu_read_unlock(); + if (read_seqcount_retry(&devnet_rename_seq, seq)) { + cond_resched(); + goto retry; + } + + return 0; +} + /** * dev_getbyhwaddr_rcu - find a device by its hardware address * @net: the applicable net namespace diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c index 6cc0481faade..5b7d0e1d0664 100644 --- a/net/core/dev_ioctl.c +++ b/net/core/dev_ioctl.c @@ -19,9 +19,8 @@ static int dev_ifname(struct net *net, struct ifreq __user *arg) { - struct net_device *dev; struct ifreq ifr; - unsigned seq; + int error; /* * Fetch the caller's info block. @@ -30,19 +29,9 @@ static int dev_ifname(struct net *net, struct ifreq __user *arg) if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) return -EFAULT; -retry: - seq = read_seqcount_begin(&devnet_rename_seq); - rcu_read_lock(); - dev = dev_get_by_index_rcu(net, ifr.ifr_ifindex); - if (!dev) { - rcu_read_unlock(); - return -ENODEV; - } - - strcpy(ifr.ifr_name, dev->name); - rcu_read_unlock(); - if (read_seqcount_retry(&devnet_rename_seq, seq)) - goto retry; + error = netdev_get_name(net, ifr.ifr_name, ifr.ifr_ifindex); + if (error) + return error; if (copy_to_user(arg, &ifr, sizeof(struct ifreq))) return -EFAULT; diff --git a/net/core/sock.c b/net/core/sock.c index 88868a9d21da..d6d024cfaaaf 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -571,9 +571,7 @@ static int sock_getbindtodevice(struct sock *sk, char __user *optval, int ret = -ENOPROTOOPT; #ifdef CONFIG_NETDEVICES struct net *net = sock_net(sk); - struct net_device *dev; char devname[IFNAMSIZ]; - unsigned seq; if (sk->sk_bound_dev_if == 0) { len = 0; @@ -584,20 +582,9 @@ static int sock_getbindtodevice(struct sock *sk, char __user *optval, if (len < IFNAMSIZ) goto out; -retry: - seq = read_seqcount_begin(&devnet_rename_seq); - rcu_read_lock(); - dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if); - ret = -ENODEV; - if (!dev) { - rcu_read_unlock(); + ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); + if (ret) goto out; - } - - strcpy(devname, dev->name); - rcu_read_unlock(); - if (read_seqcount_retry(&devnet_rename_seq, seq)) - goto retry; len = strlen(devname) + 1; -- cgit v1.2.3