Replace list_for_each_entry() by list_for_each_entry_safe() in
__btrfs_close_devices()
list_for_each_entry() {
list_replace_rcu();
call_rcu(); <-- We may free the device, if we get next
device by the current one, the page fault
may happen.
}
Signed-off-by: Azat Khuzhin <[email protected]>
Reviewed-by: Miao Xie <[email protected]>
---
V2: Add some comments from Miao into commit message
fs/btrfs/volumes.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 78b8717..1d1b595 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -616,13 +616,13 @@ static void free_device(struct rcu_head *head)
static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
{
- struct btrfs_device *device;
+ struct btrfs_device *device, *next;
if (--fs_devices->opened > 0)
return 0;
mutex_lock(&fs_devices->device_list_mutex);
- list_for_each_entry(device, &fs_devices->devices, dev_list) {
+ list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
struct btrfs_device *new_device;
struct rcu_string *name;
--
1.7.10.4