[B.A.T.M.A.N.] [PATCH 08/16] batman-adv: Check return value of try_module_get

From: Sven Eckelmann sven@narfation.org

New operations should not be started when they need an increased module reference counter and try_module_get failed.

This patch addresses Coverity #712284: Unchecked return value

Signed-off-by: Sven Eckelmann sven@narfation.org Signed-off-by: Antonio Quartulli ordex@autistici.org --- net/batman-adv/debugfs.c | 6 ++++-- net/batman-adv/icmp_socket.c | 12 ++++++++---- net/batman-adv/main.c | 10 ---------- net/batman-adv/main.h | 2 -- 4 files changed, 12 insertions(+), 18 deletions(-)

diff --git a/net/batman-adv/debugfs.c b/net/batman-adv/debugfs.c index 391d4fb..bd032bc 100644 --- a/net/batman-adv/debugfs.c +++ b/net/batman-adv/debugfs.c @@ -99,15 +99,17 @@ int batadv_debug_log(struct batadv_priv *bat_priv, const char *fmt, ...)

static int batadv_log_open(struct inode *inode, struct file *file) { + if (!try_module_get(THIS_MODULE)) + return -EBUSY; + nonseekable_open(inode, file); file->private_data = inode->i_private; - batadv_inc_module_count(); return 0; }

static int batadv_log_release(struct inode *inode, struct file *file) { - batadv_dec_module_count(); + module_put(THIS_MODULE); return 0; }

diff --git a/net/batman-adv/icmp_socket.c b/net/batman-adv/icmp_socket.c index bde3cf747..5874c0e 100644 --- a/net/batman-adv/icmp_socket.c +++ b/net/batman-adv/icmp_socket.c @@ -42,12 +42,16 @@ static int batadv_socket_open(struct inode *inode, struct file *file) unsigned int i; struct batadv_socket_client *socket_client;

+ if (!try_module_get(THIS_MODULE)) + return -EBUSY; + nonseekable_open(inode, file);

socket_client = kmalloc(sizeof(*socket_client), GFP_KERNEL); - - if (!socket_client) + if (!socket_client) { + module_put(THIS_MODULE); return -ENOMEM; + }

for (i = 0; i < ARRAY_SIZE(batadv_socket_client_hash); i++) { if (!batadv_socket_client_hash[i]) { @@ -59,6 +63,7 @@ static int batadv_socket_open(struct inode *inode, struct file *file) if (i == ARRAY_SIZE(batadv_socket_client_hash)) { pr_err("Error - can't add another packet client: maximum number of clients reached\n"); kfree(socket_client); + module_put(THIS_MODULE); return -EXFULL; }

@@ -71,7 +76,6 @@ static int batadv_socket_open(struct inode *inode, struct file *file)

file->private_data = socket_client;

- batadv_inc_module_count(); return 0; }

@@ -96,7 +100,7 @@ static int batadv_socket_release(struct inode *inode, struct file *file) spin_unlock_bh(&socket_client->lock);

kfree(socket_client); - batadv_dec_module_count(); + module_put(THIS_MODULE);

return 0; } diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c index a4a337d..f9bcfa1 100644 --- a/net/batman-adv/main.c +++ b/net/batman-adv/main.c @@ -160,16 +160,6 @@ void batadv_mesh_free(struct net_device *soft_iface) atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE); }

-void batadv_inc_module_count(void) -{ - try_module_get(THIS_MODULE); -} - -void batadv_dec_module_count(void) -{ - module_put(THIS_MODULE); -} - int batadv_is_my_mac(const uint8_t *addr) { const struct batadv_hard_iface *hard_iface; diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h index 5c0be5b..9b94f05 100644 --- a/net/batman-adv/main.h +++ b/net/batman-adv/main.h @@ -150,8 +150,6 @@ extern struct workqueue_struct *batadv_event_workqueue;

int batadv_mesh_init(struct net_device *soft_iface); void batadv_mesh_free(struct net_device *soft_iface); -void batadv_inc_module_count(void); -void batadv_dec_module_count(void); int batadv_is_my_mac(const uint8_t *addr); struct batadv_hard_iface * batadv_seq_print_text_primary_if_get(struct seq_file *seq);