Hi Jiri,

> 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 <err.h>
>       #include <fcntl.h>
>       #include <stdio.h>
>       #include <unistd.h>
> 
>       #include <sys/stat.h>
>       #include <sys/types.h>
>       #include <sys/uio.h>
> 
>       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:
> ...
>    [<ffffffff81ece010>] __alloc_skb+0x0/0x5a0
>    [<ffffffffa021886c>] vhci_create_device+0x5c/0x580 [hci_vhci]
>    [<ffffffffa0219436>] vhci_write+0x306/0x4c8 [hci_vhci]
> 
> Fixes: 23424c0d31 (Bluetooth: Add support creating virtual AMP controllers)
> Signed-off-by: Jiri Slaby <[email protected]>
> Cc: Marcel Holtmann <[email protected]>
> Cc: Gustavo Padovan <[email protected]>
> Cc: Johan Hedberg <[email protected]>
> Cc: <[email protected]>
> Cc: stable 3.13+ <[email protected]>
> ---
> drivers/bluetooth/hci_vhci.c | 1 +
> 1 file changed, 1 insertion(+)

patch has been applied to bluetooth-next tree.

Regards

Marcel

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