Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit e00bdbef authored by Reshetova, Elena's avatar Reshetova, Elena Committed by David S. Miller
Browse files

net, atm: convert eg_cache_entry.use from atomic_t to refcount_t 



refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: default avatarElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: default avatarHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Signed-off-by: default avatarDavid Windsor <dwindsor@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 93714912

net/atm/mpoa_caches.c

+7 −7
Original line number Diff line number Diff line
@@ -339,7 +339,7 @@ static eg_cache_entry *eg_cache_get_by_cache_id(__be32 cache_id, 
	entry = mpc->eg_cache;

	while (entry != NULL) {

		if (entry->ctrl_info.cache_id == cache_id) {

			atomic_inc(&entry->use);

			refcount_inc(&entry->use);

			read_unlock_irq(&mpc->egress_lock);

			return entry;

		}
@@ -360,7 +360,7 @@ static eg_cache_entry *eg_cache_get_by_tag(__be32 tag, struct mpoa_client *mpc) 
	entry = mpc->eg_cache;

	while (entry != NULL) {

		if (entry->ctrl_info.tag == tag) {

			atomic_inc(&entry->use);

			refcount_inc(&entry->use);

			read_unlock_irqrestore(&mpc->egress_lock, flags);

			return entry;

		}
@@ -382,7 +382,7 @@ static eg_cache_entry *eg_cache_get_by_vcc(struct atm_vcc *vcc, 
	entry = mpc->eg_cache;

	while (entry != NULL) {

		if (entry->shortcut == vcc) {

			atomic_inc(&entry->use);

			refcount_inc(&entry->use);

			read_unlock_irqrestore(&mpc->egress_lock, flags);

			return entry;

		}
@@ -402,7 +402,7 @@ static eg_cache_entry *eg_cache_get_by_src_ip(__be32 ipaddr, 
	entry = mpc->eg_cache;

	while (entry != NULL) {

		if (entry->latest_ip_addr == ipaddr) {

			atomic_inc(&entry->use);

			refcount_inc(&entry->use);

			read_unlock_irq(&mpc->egress_lock);

			return entry;

		}
@@ -415,7 +415,7 @@ static eg_cache_entry *eg_cache_get_by_src_ip(__be32 ipaddr, 


static void eg_cache_put(eg_cache_entry *entry)

{

	if (atomic_dec_and_test(&entry->use)) {

	if (refcount_dec_and_test(&entry->use)) {

		memset(entry, 0, sizeof(eg_cache_entry));

		kfree(entry);

	}
@@ -468,7 +468,7 @@ static eg_cache_entry *eg_cache_add_entry(struct k_message *msg, 
	dprintk("adding an egress entry, ip = %pI4, this should be our IP\n",

		&msg->content.eg_info.eg_dst_ip);



	atomic_set(&entry->use, 1);

	refcount_set(&entry->use, 1);

	dprintk("new_eg_cache_entry: about to lock\n");

	write_lock_irq(&client->egress_lock);

	entry->next = client->eg_cache;
@@ -484,7 +484,7 @@ static eg_cache_entry *eg_cache_add_entry(struct k_message *msg, 
	dprintk("new_eg_cache_entry cache_id %u\n",

		ntohl(entry->ctrl_info.cache_id));

	dprintk("mps_ip = %pI4\n", &entry->ctrl_info.mps_ip);

	atomic_inc(&entry->use);

	refcount_inc(&entry->use);



	write_unlock_irq(&client->egress_lock);

	dprintk("new_eg_cache_entry: unlocked\n");

net/atm/mpoa_caches.h

+1 −1
Original line number Diff line number Diff line
@@ -59,7 +59,7 @@ typedef struct eg_cache_entry{ 
	uint16_t             entry_state;

	__be32             latest_ip_addr;    /* The src IP address of the last packet */

	struct eg_ctrl_info  ctrl_info;

	atomic_t             use;

	refcount_t             use;

} eg_cache_entry;



struct eg_cache_ops{