The following commit has been merged in the master branch:
commit d2d489b7d851785dd4833880d31d80bd70ffa6c3
Author: Sven Eckelmann <sven(a)narfation.org>
Date: Tue Oct 30 22:01:30 2018 +0100
batman-adv: Add inconsistent multicast netlink dump detection
The netlink dump functionality transfers a large number of entries from the
kernel to userspace. It is rather likely that the transfer has to
interrupted and later continued. During that time, it can happen that
either new entries are added or removed. The userspace could than either
receive some entries multiple times or miss entries.
Commit 670dc2833d14 ("netlink: advertise incomplete dumps") introduced a
mechanism to inform userspace about this problem. Userspace can then decide
whether it is necessary or not to retry dumping the information again.
The netlink dump functions have to be switched to exclusive locks to avoid
changes while the current message is prepared. The already existing
generation sequence counter from the hash helper can be used for this
simple hash.
Reported-by: Matthias Schiffer <mschiffer(a)universe-factory.net>
Signed-off-by: Sven Eckelmann <sven(a)narfation.org>
Signed-off-by: Simon Wunderlich <sw(a)simonwunderlich.de>
diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c
index 86725d792e15..69244e4598f5 100644
--- a/net/batman-adv/multicast.c
+++ b/net/batman-adv/multicast.c
@@ -1365,22 +1365,26 @@ int batadv_mcast_mesh_info_put(struct sk_buff *msg,
* to a netlink socket
* @msg: buffer for the message
* @portid: netlink port
- * @seq: Sequence number of netlink message
+ * @cb: Control block containing additional options
* @orig_node: originator to dump the multicast flags of
*
* Return: 0 or error code.
*/
static int
-batadv_mcast_flags_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
+batadv_mcast_flags_dump_entry(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
struct batadv_orig_node *orig_node)
{
void *hdr;
- hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
- NLM_F_MULTI, BATADV_CMD_GET_MCAST_FLAGS);
+ hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
+ &batadv_netlink_family, NLM_F_MULTI,
+ BATADV_CMD_GET_MCAST_FLAGS);
if (!hdr)
return -ENOBUFS;
+ genl_dump_check_consistent(cb, hdr);
+
if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
orig_node->orig)) {
genlmsg_cancel(msg, hdr);
@@ -1405,21 +1409,26 @@ batadv_mcast_flags_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
* table to a netlink socket
* @msg: buffer for the message
* @portid: netlink port
- * @seq: Sequence number of netlink message
- * @head: bucket to dump
+ * @cb: Control block containing additional options
+ * @hash: hash to dump
+ * @bucket: bucket index to dump
* @idx_skip: How many entries to skip
*
* Return: 0 or error code.
*/
static int
-batadv_mcast_flags_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
- struct hlist_head *head, long *idx_skip)
+batadv_mcast_flags_dump_bucket(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
+ struct batadv_hashtable *hash,
+ unsigned int bucket, long *idx_skip)
{
struct batadv_orig_node *orig_node;
long idx = 0;
- rcu_read_lock();
- hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
+ spin_lock_bh(&hash->list_locks[bucket]);
+ cb->seq = atomic_read(&hash->generation) << 1 | 1;
+
+ hlist_for_each_entry(orig_node, &hash->table[bucket], hash_entry) {
if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
&orig_node->capa_initialized))
continue;
@@ -1427,9 +1436,8 @@ batadv_mcast_flags_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
if (idx < *idx_skip)
goto skip;
- if (batadv_mcast_flags_dump_entry(msg, portid, seq,
- orig_node)) {
- rcu_read_unlock();
+ if (batadv_mcast_flags_dump_entry(msg, portid, cb, orig_node)) {
+ spin_unlock_bh(&hash->list_locks[bucket]);
*idx_skip = idx;
return -EMSGSIZE;
@@ -1438,7 +1446,7 @@ batadv_mcast_flags_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
skip:
idx++;
}
- rcu_read_unlock();
+ spin_unlock_bh(&hash->list_locks[bucket]);
return 0;
}
@@ -1447,7 +1455,7 @@ skip:
* __batadv_mcast_flags_dump() - dump multicast flags table to a netlink socket
* @msg: buffer for the message
* @portid: netlink port
- * @seq: Sequence number of netlink message
+ * @cb: Control block containing additional options
* @bat_priv: the bat priv with all the soft interface information
* @bucket: current bucket to dump
* @idx: index in current bucket to the next entry to dump
@@ -1455,19 +1463,17 @@ skip:
* Return: 0 or error code.
*/
static int
-__batadv_mcast_flags_dump(struct sk_buff *msg, u32 portid, u32 seq,
+__batadv_mcast_flags_dump(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
struct batadv_priv *bat_priv, long *bucket, long *idx)
{
struct batadv_hashtable *hash = bat_priv->orig_hash;
long bucket_tmp = *bucket;
- struct hlist_head *head;
long idx_tmp = *idx;
while (bucket_tmp < hash->size) {
- head = &hash->table[bucket_tmp];
-
- if (batadv_mcast_flags_dump_bucket(msg, portid, seq, head,
- &idx_tmp))
+ if (batadv_mcast_flags_dump_bucket(msg, portid, cb, hash,
+ *bucket, &idx_tmp))
break;
bucket_tmp++;
@@ -1550,8 +1556,7 @@ int batadv_mcast_flags_dump(struct sk_buff *msg, struct netlink_callback *cb)
return ret;
bat_priv = netdev_priv(primary_if->soft_iface);
- ret = __batadv_mcast_flags_dump(msg, portid, cb->nlh->nlmsg_seq,
- bat_priv, bucket, idx);
+ ret = __batadv_mcast_flags_dump(msg, portid, cb, bat_priv, bucket, idx);
batadv_hardif_put(primary_if);
return ret;
--
LinuxNextTracking
The following commit has been merged in the master branch:
commit 24d71b92321ab994585c816ede8c12857985d924
Author: Sven Eckelmann <sven(a)narfation.org>
Date: Tue Oct 30 22:01:27 2018 +0100
batman-adv: Add inconsistent claim netlink dump detection
The netlink dump functionality transfers a large number of entries from the
kernel to userspace. It is rather likely that the transfer has to
interrupted and later continued. During that time, it can happen that
either new entries are added or removed. The userspace could than either
receive some entries multiple times or miss entries.
Commit 670dc2833d14 ("netlink: advertise incomplete dumps") introduced a
mechanism to inform userspace about this problem. Userspace can then decide
whether it is necessary or not to retry dumping the information again.
The netlink dump functions have to be switched to exclusive locks to avoid
changes while the current message is prepared. The already existing
generation sequence counter from the hash helper can be used for this
simple hash.
Reported-by: Matthias Schiffer <mschiffer(a)universe-factory.net>
Signed-off-by: Sven Eckelmann <sven(a)narfation.org>
Signed-off-by: Simon Wunderlich <sw(a)simonwunderlich.de>
diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c
index 9f3747346d29..5fdde2947802 100644
--- a/net/batman-adv/bridge_loop_avoidance.c
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -2094,14 +2094,15 @@ out:
* to a netlink socket
* @msg: buffer for the message
* @portid: netlink port
- * @seq: Sequence number of netlink message
+ * @cb: Control block containing additional options
* @primary_if: primary interface
* @claim: entry to dump
*
* Return: 0 or error code.
*/
static int
-batadv_bla_claim_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
+batadv_bla_claim_dump_entry(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
struct batadv_hard_iface *primary_if,
struct batadv_bla_claim *claim)
{
@@ -2111,13 +2112,16 @@ batadv_bla_claim_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
void *hdr;
int ret = -EINVAL;
- hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
- NLM_F_MULTI, BATADV_CMD_GET_BLA_CLAIM);
+ hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
+ &batadv_netlink_family, NLM_F_MULTI,
+ BATADV_CMD_GET_BLA_CLAIM);
if (!hdr) {
ret = -ENOBUFS;
goto out;
}
+ genl_dump_check_consistent(cb, hdr);
+
is_own = batadv_compare_eth(claim->backbone_gw->orig,
primary_addr);
@@ -2153,28 +2157,33 @@ out:
* to a netlink socket
* @msg: buffer for the message
* @portid: netlink port
- * @seq: Sequence number of netlink message
+ * @cb: Control block containing additional options
* @primary_if: primary interface
- * @head: bucket to dump
+ * @hash: hash to dump
+ * @bucket: bucket index to dump
* @idx_skip: How many entries to skip
*
* Return: always 0.
*/
static int
-batadv_bla_claim_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
+batadv_bla_claim_dump_bucket(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
struct batadv_hard_iface *primary_if,
- struct hlist_head *head, int *idx_skip)
+ struct batadv_hashtable *hash, unsigned int bucket,
+ int *idx_skip)
{
struct batadv_bla_claim *claim;
int idx = 0;
int ret = 0;
- rcu_read_lock();
- hlist_for_each_entry_rcu(claim, head, hash_entry) {
+ spin_lock_bh(&hash->list_locks[bucket]);
+ cb->seq = atomic_read(&hash->generation) << 1 | 1;
+
+ hlist_for_each_entry(claim, &hash->table[bucket], hash_entry) {
if (idx++ < *idx_skip)
continue;
- ret = batadv_bla_claim_dump_entry(msg, portid, seq,
+ ret = batadv_bla_claim_dump_entry(msg, portid, cb,
primary_if, claim);
if (ret) {
*idx_skip = idx - 1;
@@ -2184,7 +2193,7 @@ batadv_bla_claim_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
*idx_skip = 0;
unlock:
- rcu_read_unlock();
+ spin_unlock_bh(&hash->list_locks[bucket]);
return ret;
}
@@ -2204,7 +2213,6 @@ int batadv_bla_claim_dump(struct sk_buff *msg, struct netlink_callback *cb)
struct batadv_hashtable *hash;
struct batadv_priv *bat_priv;
int bucket = cb->args[0];
- struct hlist_head *head;
int idx = cb->args[1];
int ifindex;
int ret = 0;
@@ -2230,11 +2238,8 @@ int batadv_bla_claim_dump(struct sk_buff *msg, struct netlink_callback *cb)
}
while (bucket < hash->size) {
- head = &hash->table[bucket];
-
- if (batadv_bla_claim_dump_bucket(msg, portid,
- cb->nlh->nlmsg_seq,
- primary_if, head, &idx))
+ if (batadv_bla_claim_dump_bucket(msg, portid, cb, primary_if,
+ hash, bucket, &idx))
break;
bucket++;
}
--
LinuxNextTracking
The following commit has been merged in the master branch:
commit 6f81652a4713e49afa4e1f6923c61e2e165afa08
Author: Sven Eckelmann <sven(a)narfation.org>
Date: Tue Oct 30 22:01:28 2018 +0100
batman-adv: Add inconsistent dat netlink dump detection
The netlink dump functionality transfers a large number of entries from the
kernel to userspace. It is rather likely that the transfer has to
interrupted and later continued. During that time, it can happen that
either new entries are added or removed. The userspace could than either
receive some entries multiple times or miss entries.
Commit 670dc2833d14 ("netlink: advertise incomplete dumps") introduced a
mechanism to inform userspace about this problem. Userspace can then decide
whether it is necessary or not to retry dumping the information again.
The netlink dump functions have to be switched to exclusive locks to avoid
changes while the current message is prepared. The already existing
generation sequence counter from the hash helper can be used for this
simple hash.
Reported-by: Matthias Schiffer <mschiffer(a)universe-factory.net>
Signed-off-by: Sven Eckelmann <sven(a)narfation.org>
Signed-off-by: Simon Wunderlich <sw(a)simonwunderlich.de>
diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c
index a60bacf7120b..b9ffe1826527 100644
--- a/net/batman-adv/distributed-arp-table.c
+++ b/net/batman-adv/distributed-arp-table.c
@@ -863,23 +863,27 @@ out:
* netlink socket
* @msg: buffer for the message
* @portid: netlink port
- * @seq: Sequence number of netlink message
+ * @cb: Control block containing additional options
* @dat_entry: entry to dump
*
* Return: 0 or error code.
*/
static int
-batadv_dat_cache_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
+batadv_dat_cache_dump_entry(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
struct batadv_dat_entry *dat_entry)
{
int msecs;
void *hdr;
- hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
- NLM_F_MULTI, BATADV_CMD_GET_DAT_CACHE);
+ hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
+ &batadv_netlink_family, NLM_F_MULTI,
+ BATADV_CMD_GET_DAT_CACHE);
if (!hdr)
return -ENOBUFS;
+ genl_dump_check_consistent(cb, hdr);
+
msecs = jiffies_to_msecs(jiffies - dat_entry->last_update);
if (nla_put_in_addr(msg, BATADV_ATTR_DAT_CACHE_IP4ADDRESS,
@@ -901,27 +905,31 @@ batadv_dat_cache_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
* a netlink socket
* @msg: buffer for the message
* @portid: netlink port
- * @seq: Sequence number of netlink message
- * @head: bucket to dump
+ * @cb: Control block containing additional options
+ * @hash: hash to dump
+ * @bucket: bucket index to dump
* @idx_skip: How many entries to skip
*
* Return: 0 or error code.
*/
static int
-batadv_dat_cache_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
- struct hlist_head *head, int *idx_skip)
+batadv_dat_cache_dump_bucket(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
+ struct batadv_hashtable *hash, unsigned int bucket,
+ int *idx_skip)
{
struct batadv_dat_entry *dat_entry;
int idx = 0;
- rcu_read_lock();
- hlist_for_each_entry_rcu(dat_entry, head, hash_entry) {
+ spin_lock_bh(&hash->list_locks[bucket]);
+ cb->seq = atomic_read(&hash->generation) << 1 | 1;
+
+ hlist_for_each_entry(dat_entry, &hash->table[bucket], hash_entry) {
if (idx < *idx_skip)
goto skip;
- if (batadv_dat_cache_dump_entry(msg, portid, seq,
- dat_entry)) {
- rcu_read_unlock();
+ if (batadv_dat_cache_dump_entry(msg, portid, cb, dat_entry)) {
+ spin_unlock_bh(&hash->list_locks[bucket]);
*idx_skip = idx;
return -EMSGSIZE;
@@ -930,7 +938,7 @@ batadv_dat_cache_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
skip:
idx++;
}
- rcu_read_unlock();
+ spin_unlock_bh(&hash->list_locks[bucket]);
return 0;
}
@@ -951,7 +959,6 @@ int batadv_dat_cache_dump(struct sk_buff *msg, struct netlink_callback *cb)
struct batadv_hashtable *hash;
struct batadv_priv *bat_priv;
int bucket = cb->args[0];
- struct hlist_head *head;
int idx = cb->args[1];
int ifindex;
int ret = 0;
@@ -977,10 +984,7 @@ int batadv_dat_cache_dump(struct sk_buff *msg, struct netlink_callback *cb)
}
while (bucket < hash->size) {
- head = &hash->table[bucket];
-
- if (batadv_dat_cache_dump_bucket(msg, portid,
- cb->nlh->nlmsg_seq, head,
+ if (batadv_dat_cache_dump_bucket(msg, portid, cb, hash, bucket,
&idx))
break;
--
LinuxNextTracking
The following commit has been merged in the master branch:
commit b00d0e6a2cb143ccc2b75a930f0d5a46033ea7aa
Author: Sven Eckelmann <sven(a)narfation.org>
Date: Tue Oct 30 22:01:26 2018 +0100
batman-adv: Add inconsistent backbone netlink dump detection
The netlink dump functionality transfers a large number of entries from the
kernel to userspace. It is rather likely that the transfer has to
interrupted and later continued. During that time, it can happen that
either new entries are added or removed. The userspace could than either
receive some entries multiple times or miss entries.
Commit 670dc2833d14 ("netlink: advertise incomplete dumps") introduced a
mechanism to inform userspace about this problem. Userspace can then decide
whether it is necessary or not to retry dumping the information again.
The netlink dump functions have to be switched to exclusive locks to avoid
changes while the current message is prepared. The already existing
generation sequence counter from the hash helper can be used for this
simple hash.
Reported-by: Matthias Schiffer <mschiffer(a)universe-factory.net>
Signed-off-by: Sven Eckelmann <sven(a)narfation.org>
Signed-off-by: Simon Wunderlich <sw(a)simonwunderlich.de>
diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c
index 5f1aeeded0e3..9f3747346d29 100644
--- a/net/batman-adv/bridge_loop_avoidance.c
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -2325,14 +2325,15 @@ out:
* netlink socket
* @msg: buffer for the message
* @portid: netlink port
- * @seq: Sequence number of netlink message
+ * @cb: Control block containing additional options
* @primary_if: primary interface
* @backbone_gw: entry to dump
*
* Return: 0 or error code.
*/
static int
-batadv_bla_backbone_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
+batadv_bla_backbone_dump_entry(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
struct batadv_hard_iface *primary_if,
struct batadv_bla_backbone_gw *backbone_gw)
{
@@ -2343,13 +2344,16 @@ batadv_bla_backbone_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
void *hdr;
int ret = -EINVAL;
- hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
- NLM_F_MULTI, BATADV_CMD_GET_BLA_BACKBONE);
+ hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
+ &batadv_netlink_family, NLM_F_MULTI,
+ BATADV_CMD_GET_BLA_BACKBONE);
if (!hdr) {
ret = -ENOBUFS;
goto out;
}
+ genl_dump_check_consistent(cb, hdr);
+
is_own = batadv_compare_eth(backbone_gw->orig, primary_addr);
spin_lock_bh(&backbone_gw->crc_lock);
@@ -2386,28 +2390,33 @@ out:
* a netlink socket
* @msg: buffer for the message
* @portid: netlink port
- * @seq: Sequence number of netlink message
+ * @cb: Control block containing additional options
* @primary_if: primary interface
- * @head: bucket to dump
+ * @hash: hash to dump
+ * @bucket: bucket index to dump
* @idx_skip: How many entries to skip
*
* Return: always 0.
*/
static int
-batadv_bla_backbone_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
+batadv_bla_backbone_dump_bucket(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
struct batadv_hard_iface *primary_if,
- struct hlist_head *head, int *idx_skip)
+ struct batadv_hashtable *hash,
+ unsigned int bucket, int *idx_skip)
{
struct batadv_bla_backbone_gw *backbone_gw;
int idx = 0;
int ret = 0;
- rcu_read_lock();
- hlist_for_each_entry_rcu(backbone_gw, head, hash_entry) {
+ spin_lock_bh(&hash->list_locks[bucket]);
+ cb->seq = atomic_read(&hash->generation) << 1 | 1;
+
+ hlist_for_each_entry(backbone_gw, &hash->table[bucket], hash_entry) {
if (idx++ < *idx_skip)
continue;
- ret = batadv_bla_backbone_dump_entry(msg, portid, seq,
+ ret = batadv_bla_backbone_dump_entry(msg, portid, cb,
primary_if, backbone_gw);
if (ret) {
*idx_skip = idx - 1;
@@ -2417,7 +2426,7 @@ batadv_bla_backbone_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
*idx_skip = 0;
unlock:
- rcu_read_unlock();
+ spin_unlock_bh(&hash->list_locks[bucket]);
return ret;
}
@@ -2437,7 +2446,6 @@ int batadv_bla_backbone_dump(struct sk_buff *msg, struct netlink_callback *cb)
struct batadv_hashtable *hash;
struct batadv_priv *bat_priv;
int bucket = cb->args[0];
- struct hlist_head *head;
int idx = cb->args[1];
int ifindex;
int ret = 0;
@@ -2463,11 +2471,8 @@ int batadv_bla_backbone_dump(struct sk_buff *msg, struct netlink_callback *cb)
}
while (bucket < hash->size) {
- head = &hash->table[bucket];
-
- if (batadv_bla_backbone_dump_bucket(msg, portid,
- cb->nlh->nlmsg_seq,
- primary_if, head, &idx))
+ if (batadv_bla_backbone_dump_bucket(msg, portid, cb, primary_if,
+ hash, bucket, &idx))
break;
bucket++;
}
--
LinuxNextTracking
The following commit has been merged in the master branch:
commit 05abd7bcc9cdbedf9deff27fe0766c70c4f2ae0d
Author: Sven Eckelmann <sven(a)narfation.org>
Date: Tue Oct 30 22:01:25 2018 +0100
batman-adv: Store modification counter via hash helpers
Multiple datastructures use the hash helper functions to add and remove
entries from the simple hlist based hashes. These are often also dumped to
userspace via netlink and thus should have a generation sequence counter.
Reported-by: Matthias Schiffer <mschiffer(a)universe-factory.net>
Signed-off-by: Sven Eckelmann <sven(a)narfation.org>
Signed-off-by: Simon Wunderlich <sw(a)simonwunderlich.de>
diff --git a/net/batman-adv/hash.c b/net/batman-adv/hash.c
index 7b49e4001778..9194f4d891b1 100644
--- a/net/batman-adv/hash.c
+++ b/net/batman-adv/hash.c
@@ -32,6 +32,8 @@ static void batadv_hash_init(struct batadv_hashtable *hash)
INIT_HLIST_HEAD(&hash->table[i]);
spin_lock_init(&hash->list_locks[i]);
}
+
+ atomic_set(&hash->generation, 0);
}
/**
diff --git a/net/batman-adv/hash.h b/net/batman-adv/hash.h
index 9490a7ca2ba6..0e36fa1c7c3e 100644
--- a/net/batman-adv/hash.h
+++ b/net/batman-adv/hash.h
@@ -21,6 +21,7 @@
#include "main.h"
+#include <linux/atomic.h>
#include <linux/compiler.h>
#include <linux/list.h>
#include <linux/rculist.h>
@@ -58,6 +59,9 @@ struct batadv_hashtable {
/** @size: size of hashtable */
u32 size;
+
+ /** @generation: current (generation) sequence number */
+ atomic_t generation;
};
/* allocates and clears the hash */
@@ -112,6 +116,7 @@ static inline int batadv_hash_add(struct batadv_hashtable *hash,
/* no duplicate found in list, add new element */
hlist_add_head_rcu(data_node, head);
+ atomic_inc(&hash->generation);
ret = 0;
@@ -154,6 +159,7 @@ static inline void *batadv_hash_remove(struct batadv_hashtable *hash,
data_save = node;
hlist_del_rcu(node);
+ atomic_inc(&hash->generation);
break;
}
spin_unlock_bh(&hash->list_locks[index]);
--
LinuxNextTracking
The following commit has been merged in the master branch:
commit fb69be697916a2d0a9badcdef7f20fcfad1233bc
Author: Sven Eckelmann <sven(a)narfation.org>
Date: Tue Oct 30 22:01:24 2018 +0100
batman-adv: Add inconsistent hardif netlink dump detection
The netlink dump functionality transfers a large number of entries from the
kernel to userspace. It is rather likely that the transfer has to
interrupted and later continued. During that time, it can happen that
either new entries are added or removed. The userspace could than either
receive some entries multiple times or miss entries.
Commit 670dc2833d14 ("netlink: advertise incomplete dumps") introduced a
mechanism to inform userspace about this problem. Userspace can then decide
whether it is necessary or not to retry dumping the information again.
The netlink dump functions have to be switched to exclusive locks to avoid
changes while the current message is prepared. And an external generation
sequence counter is introduced which tracks all modifications of the list.
Reported-by: Matthias Schiffer <mschiffer(a)universe-factory.net>
Signed-off-by: Sven Eckelmann <sven(a)narfation.org>
Signed-off-by: Simon Wunderlich <sw(a)simonwunderlich.de>
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index 781c5b6e6e8e..508f4416dfc9 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -951,6 +951,7 @@ batadv_hardif_add_interface(struct net_device *net_dev)
batadv_check_known_mac_addr(hard_iface->net_dev);
kref_get(&hard_iface->refcount);
list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
+ batadv_hardif_generation++;
return hard_iface;
@@ -993,6 +994,7 @@ void batadv_hardif_remove_interfaces(void)
list_for_each_entry_safe(hard_iface, hard_iface_tmp,
&batadv_hardif_list, list) {
list_del_rcu(&hard_iface->list);
+ batadv_hardif_generation++;
batadv_hardif_remove_interface(hard_iface);
}
rtnl_unlock();
@@ -1054,6 +1056,7 @@ static int batadv_hard_if_event(struct notifier_block *this,
case NETDEV_UNREGISTER:
case NETDEV_PRE_TYPE_CHANGE:
list_del_rcu(&hard_iface->list);
+ batadv_hardif_generation++;
batadv_hardif_remove_interface(hard_iface);
break;
diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c
index c75e47826949..d1ed839fd32b 100644
--- a/net/batman-adv/main.c
+++ b/net/batman-adv/main.c
@@ -74,6 +74,7 @@
* list traversals just rcu-locked
*/
struct list_head batadv_hardif_list;
+unsigned int batadv_hardif_generation;
static int (*batadv_rx_handler[256])(struct sk_buff *skb,
struct batadv_hard_iface *recv_if);
diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h
index b68a41190eb0..b572066325e4 100644
--- a/net/batman-adv/main.h
+++ b/net/batman-adv/main.h
@@ -247,6 +247,7 @@ static inline int batadv_print_vid(unsigned short vid)
}
extern struct list_head batadv_hardif_list;
+extern unsigned int batadv_hardif_generation;
extern unsigned char batadv_broadcast_addr[];
extern struct workqueue_struct *batadv_event_workqueue;
diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c
index 0d9459b69bdb..2dc3304cee54 100644
--- a/net/batman-adv/netlink.c
+++ b/net/batman-adv/netlink.c
@@ -29,11 +29,11 @@
#include <linux/if_ether.h>
#include <linux/init.h>
#include <linux/kernel.h>
+#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/netlink.h>
#include <linux/printk.h>
-#include <linux/rculist.h>
-#include <linux/rcupdate.h>
+#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
#include <linux/stddef.h>
#include <linux/types.h>
@@ -445,23 +445,27 @@ out:
* batadv_netlink_dump_hardif_entry() - Dump one hard interface into a message
* @msg: Netlink message to dump into
* @portid: Port making netlink request
- * @seq: Sequence number of netlink message
+ * @cb: Control block containing additional options
* @hard_iface: Hard interface to dump
*
* Return: error code, or 0 on success
*/
static int
-batadv_netlink_dump_hardif_entry(struct sk_buff *msg, u32 portid, u32 seq,
+batadv_netlink_dump_hardif_entry(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
struct batadv_hard_iface *hard_iface)
{
struct net_device *net_dev = hard_iface->net_dev;
void *hdr;
- hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, NLM_F_MULTI,
+ hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
+ &batadv_netlink_family, NLM_F_MULTI,
BATADV_CMD_GET_HARDIFS);
if (!hdr)
return -EMSGSIZE;
+ genl_dump_check_consistent(cb, hdr);
+
if (nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
net_dev->ifindex) ||
nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
@@ -498,7 +502,6 @@ batadv_netlink_dump_hardifs(struct sk_buff *msg, struct netlink_callback *cb)
struct batadv_hard_iface *hard_iface;
int ifindex;
int portid = NETLINK_CB(cb->skb).portid;
- int seq = cb->nlh->nlmsg_seq;
int skip = cb->args[0];
int i = 0;
@@ -516,23 +519,24 @@ batadv_netlink_dump_hardifs(struct sk_buff *msg, struct netlink_callback *cb)
return -ENODEV;
}
- rcu_read_lock();
+ rtnl_lock();
+ cb->seq = batadv_hardif_generation << 1 | 1;
- list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
+ list_for_each_entry(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->soft_iface != soft_iface)
continue;
if (i++ < skip)
continue;
- if (batadv_netlink_dump_hardif_entry(msg, portid, seq,
+ if (batadv_netlink_dump_hardif_entry(msg, portid, cb,
hard_iface)) {
i--;
break;
}
}
- rcu_read_unlock();
+ rtnl_unlock();
dev_put(soft_iface);
--
LinuxNextTracking
The following commit has been merged in the master branch:
commit 694127c1dd494d3796e1627389a4cff7ee19e613
Author: Sven Eckelmann <sven(a)narfation.org>
Date: Sun Oct 21 11:30:32 2018 +0200
batman-adv: Fix description for BATMAN_ADV_DEBUG
The debug messages of batman-adv are not printed to the kernel log at all
but can be stored (depending on the compile setting) in the tracing buffer
or the batadv specific log buffer. There is also no debug module parameter
but a batadv netdev specific log_level setting to enable/disable different
classes of debug messages at runtime.
Signed-off-by: Sven Eckelmann <sven(a)narfation.org>
Signed-off-by: Simon Wunderlich <sw(a)simonwunderlich.de>
diff --git a/net/batman-adv/Kconfig b/net/batman-adv/Kconfig
index 7b0e1fcddfa7..082e96060bc2 100644
--- a/net/batman-adv/Kconfig
+++ b/net/batman-adv/Kconfig
@@ -104,8 +104,9 @@ config BATMAN_ADV_DEBUG
help
This is an option for use by developers; most people should
say N here. This enables compilation of support for
- outputting debugging information to the kernel log. The
- output is controlled via the module parameter debug.
+ outputting debugging information to the debugfs log or tracing
+ buffer. The output is controlled via the batadv netdev specific
+ log_level setting.
config BATMAN_ADV_TRACING
bool "B.A.T.M.A.N. tracing support"
--
LinuxNextTracking
The following commit has been merged in the master branch:
commit 0dacc7fab623be97bda7aefe0d1d8d68cebb4218
Author: Sven Eckelmann <sven(a)narfation.org>
Date: Sun Oct 21 11:30:31 2018 +0200
batman-adv: Allow to use BATMAN_ADV_DEBUG without BATMAN_ADV_DEBUGFS
The BATMAN_ADV_DEBUGFS portion of batman-adv is marked as deprecated. Thus
all required functionality should be available without it. The debug log
was already modified to also output via the kernel tracing function but
still retained its BATMAN_ADV_DEBUGFS functionality.
Separate the entry point for the debug log from the debugfs portions to
make it possible to build with BATMAN_ADV_DEBUG and without
BATMAN_ADV_DEBUGFS.
Signed-off-by: Sven Eckelmann <sven(a)narfation.org>
Signed-off-by: Simon Wunderlich <sw(a)simonwunderlich.de>
diff --git a/net/batman-adv/Kconfig b/net/batman-adv/Kconfig
index f75816f58107..7b0e1fcddfa7 100644
--- a/net/batman-adv/Kconfig
+++ b/net/batman-adv/Kconfig
@@ -100,7 +100,7 @@ config BATMAN_ADV_DEBUGFS
config BATMAN_ADV_DEBUG
bool "B.A.T.M.A.N. debugging"
- depends on BATMAN_ADV_DEBUGFS
+ depends on BATMAN_ADV
help
This is an option for use by developers; most people should
say N here. This enables compilation of support for
diff --git a/net/batman-adv/log.c b/net/batman-adv/log.c
index 6beb5f067810..02e55b78132f 100644
--- a/net/batman-adv/log.c
+++ b/net/batman-adv/log.c
@@ -43,6 +43,8 @@
#include "debugfs.h"
#include "trace.h"
+#ifdef CONFIG_BATMAN_ADV_DEBUGFS
+
#define BATADV_LOG_BUFF_MASK (batadv_log_buff_len - 1)
static const int batadv_log_buff_len = BATADV_LOG_BUF_LEN;
@@ -92,33 +94,6 @@ static int batadv_fdebug_log(struct batadv_priv_debug_log *debug_log,
return 0;
}
-/**
- * batadv_debug_log() - Add debug log entry
- * @bat_priv: the bat priv with all the soft interface information
- * @fmt: format string
- *
- * Return: 0 on success or negative error number in case of failure
- */
-int batadv_debug_log(struct batadv_priv *bat_priv, const char *fmt, ...)
-{
- struct va_format vaf;
- va_list args;
-
- va_start(args, fmt);
-
- vaf.fmt = fmt;
- vaf.va = &args;
-
- batadv_fdebug_log(bat_priv->debug_log, "[%10u] %pV",
- jiffies_to_msecs(jiffies), &vaf);
-
- trace_batadv_dbg(bat_priv, &vaf);
-
- va_end(args);
-
- return 0;
-}
-
static int batadv_log_open(struct inode *inode, struct file *file)
{
if (!try_module_get(THIS_MODULE))
@@ -259,3 +234,34 @@ void batadv_debug_log_cleanup(struct batadv_priv *bat_priv)
kfree(bat_priv->debug_log);
bat_priv->debug_log = NULL;
}
+
+#endif /* CONFIG_BATMAN_ADV_DEBUGFS */
+
+/**
+ * batadv_debug_log() - Add debug log entry
+ * @bat_priv: the bat priv with all the soft interface information
+ * @fmt: format string
+ *
+ * Return: 0 on success or negative error number in case of failure
+ */
+int batadv_debug_log(struct batadv_priv *bat_priv, const char *fmt, ...)
+{
+ struct va_format vaf;
+ va_list args;
+
+ va_start(args, fmt);
+
+ vaf.fmt = fmt;
+ vaf.va = &args;
+
+#ifdef CONFIG_BATMAN_ADV_DEBUGFS
+ batadv_fdebug_log(bat_priv->debug_log, "[%10u] %pV",
+ jiffies_to_msecs(jiffies), &vaf);
+#endif
+
+ trace_batadv_dbg(bat_priv, &vaf);
+
+ va_end(args);
+
+ return 0;
+}
--
LinuxNextTracking
The following commit has been merged in the master branch:
commit a5dac4da72f59f9565af747f0e4a2d943f902240
Author: Sven Eckelmann <sven(a)narfation.org>
Date: Sun Oct 21 11:30:29 2018 +0200
batman-adv: Add includes for deprecation warning
The commit 00caf6a2b318 ("batman-adv: Mark debugfs functionality as
deprecated") introduced various messages to inform the user about the
deprecation of the debugfs based functionality. The messages also include
the context/task in which this problem was observed.
The datastructures and functions to access this information require special
headers. These should be included directly instead of depending on a more
complex and fragile include chain.
Signed-off-by: Sven Eckelmann <sven(a)narfation.org>
Signed-off-by: Simon Wunderlich <sw(a)simonwunderlich.de>
diff --git a/net/batman-adv/debugfs.c b/net/batman-adv/debugfs.c
index 8b608a2e2653..d4a7702e48d8 100644
--- a/net/batman-adv/debugfs.c
+++ b/net/batman-adv/debugfs.c
@@ -19,6 +19,7 @@
#include "debugfs.h"
#include "main.h"
+#include <asm/current.h>
#include <linux/dcache.h>
#include <linux/debugfs.h>
#include <linux/err.h>
@@ -27,6 +28,7 @@
#include <linux/fs.h>
#include <linux/netdevice.h>
#include <linux/printk.h>
+#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/stat.h>
#include <linux/stddef.h>
--
LinuxNextTracking