From 13407376b255325fa817798800117a839f3aa055 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Sat, 19 Mar 2016 11:49:43 +0100 Subject: [PATCH] Bluetooth: vhci: purge unhandled skbs The write handler allocates skbs and queues them into data->readq. Read side should read them, if there is any. If there is none, skbs should be dropped by hdev->flush. But this happens only if the device is HCI_UP, i.e. hdev->power_on work was triggered already. When it was not, skbs stay allocated in the queue when /dev/vhci is closed. So purge the queue in ->release. Program to reproduce: #include #include #include #include #include #include #include int main() { char buf[] = { 0xff, 0 }; struct iovec iov = { .iov_base = buf, .iov_len = sizeof(buf), }; int fd; while (1) { fd = open("/dev/vhci", O_RDWR); if (fd < 0) err(1, "open"); usleep(50); if (writev(fd, &iov, 1) < 0) err(1, "writev"); usleep(50); close(fd); } return 0; } Result: kmemleak: 4609 new suspected memory leaks unreferenced object 0xffff88059f4d5440 (size 232): comm "vhci", pid 1084, jiffies 4294912542 (age 37569.296s) hex dump (first 32 bytes): 20 f0 23 87 05 88 ff ff 20 f0 23 87 05 88 ff ff .#..... .#..... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: ... [] __alloc_skb+0x0/0x5a0 [] vhci_create_device+0x5c/0x580 [hci_vhci] [] vhci_write+0x306/0x4c8 [hci_vhci] Fixes: 23424c0d31 (Bluetooth: Add support creating virtual AMP controllers) Signed-off-by: Jiri Slaby Signed-off-by: Marcel Holtmann Cc: stable 3.13+ --- drivers/bluetooth/hci_vhci.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/bluetooth/hci_vhci.c b/drivers/bluetooth/hci_vhci.c index 3ec580e38c17..f67ea1c090cb 100644 --- a/drivers/bluetooth/hci_vhci.c +++ b/drivers/bluetooth/hci_vhci.c @@ -344,6 +344,7 @@ static int vhci_release(struct inode *inode, struct file *file) hci_free_dev(hdev); } + skb_queue_purge(&data->readq); file->private_data = NULL; kfree(data); -- 2.30.2