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-rw-r--r--fs/fuse/cuse.c36
1 files changed, 22 insertions, 14 deletions
diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c
index ee8d550..e397b67 100644
--- a/fs/fuse/cuse.c
+++ b/fs/fuse/cuse.c
@@ -45,7 +45,6 @@
#include <linux/miscdevice.h>
#include <linux/mutex.h>
#include <linux/slab.h>
-#include <linux/spinlock.h>
#include <linux/stat.h>
#include <linux/module.h>
@@ -63,7 +62,7 @@ struct cuse_conn {
bool unrestricted_ioctl;
};
-static DEFINE_SPINLOCK(cuse_lock); /* protects cuse_conntbl */
+static DEFINE_MUTEX(cuse_lock); /* protects registration */
static struct list_head cuse_conntbl[CUSE_CONNTBL_LEN];
static struct class *cuse_class;
@@ -114,14 +113,14 @@ static int cuse_open(struct inode *inode, struct file *file)
int rc;
/* look up and get the connection */
- spin_lock(&cuse_lock);
+ mutex_lock(&cuse_lock);
list_for_each_entry(pos, cuse_conntbl_head(devt), list)
if (pos->dev->devt == devt) {
fuse_conn_get(&pos->fc);
cc = pos;
break;
}
- spin_unlock(&cuse_lock);
+ mutex_unlock(&cuse_lock);
/* dead? */
if (!cc)
@@ -267,7 +266,7 @@ static int cuse_parse_one(char **pp, char *end, char **keyp, char **valp)
static int cuse_parse_devinfo(char *p, size_t len, struct cuse_devinfo *devinfo)
{
char *end = p + len;
- char *key, *val;
+ char *uninitialized_var(key), *uninitialized_var(val);
int rc;
while (true) {
@@ -305,14 +304,14 @@ static void cuse_gendev_release(struct device *dev)
*/
static void cuse_process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
{
- struct cuse_conn *cc = fc_to_cc(fc);
+ struct cuse_conn *cc = fc_to_cc(fc), *pos;
struct cuse_init_out *arg = req->out.args[0].value;
struct page *page = req->pages[0];
struct cuse_devinfo devinfo = { };
struct device *dev;
struct cdev *cdev;
dev_t devt;
- int rc;
+ int rc, i;
if (req->out.h.error ||
arg->major != FUSE_KERNEL_VERSION || arg->minor < 11) {
@@ -356,15 +355,24 @@ static void cuse_process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
dev_set_drvdata(dev, cc);
dev_set_name(dev, "%s", devinfo.name);
+ mutex_lock(&cuse_lock);
+
+ /* make sure the device-name is unique */
+ for (i = 0; i < CUSE_CONNTBL_LEN; ++i) {
+ list_for_each_entry(pos, &cuse_conntbl[i], list)
+ if (!strcmp(dev_name(pos->dev), dev_name(dev)))
+ goto err_unlock;
+ }
+
rc = device_add(dev);
if (rc)
- goto err_device;
+ goto err_unlock;
/* register cdev */
rc = -ENOMEM;
cdev = cdev_alloc();
if (!cdev)
- goto err_device;
+ goto err_unlock;
cdev->owner = THIS_MODULE;
cdev->ops = &cuse_frontend_fops;
@@ -377,9 +385,8 @@ static void cuse_process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
cc->cdev = cdev;
/* make the device available */
- spin_lock(&cuse_lock);
list_add(&cc->list, cuse_conntbl_head(devt));
- spin_unlock(&cuse_lock);
+ mutex_unlock(&cuse_lock);
/* announce device availability */
dev_set_uevent_suppress(dev, 0);
@@ -391,7 +398,8 @@ out:
err_cdev:
cdev_del(cdev);
-err_device:
+err_unlock:
+ mutex_unlock(&cuse_lock);
put_device(dev);
err_region:
unregister_chrdev_region(devt, 1);
@@ -520,9 +528,9 @@ static int cuse_channel_release(struct inode *inode, struct file *file)
int rc;
/* remove from the conntbl, no more access from this point on */
- spin_lock(&cuse_lock);
+ mutex_lock(&cuse_lock);
list_del_init(&cc->list);
- spin_unlock(&cuse_lock);
+ mutex_unlock(&cuse_lock);
/* remove device */
if (cc->dev)
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