From 090264e508c20baa0c3eea5a7d8eea4db84a29cc Mon Sep 17 00:00:00 2001 From: Jean-Francois Moine Date: Thu, 12 Feb 2009 08:05:45 -0300 Subject: [PATCH] V4L/DVB (10620): gspca - main: More checks of the device disconnection. - prevent application oops when the device is disconnected - wake up the application at disconnection time - check the disconnection in ioctl dqbuf and poll Signed-off-by: Jean-Francois Moine Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/gspca/gspca.c | 105 +++++++++++++++++++++--------- 1 file changed, 74 insertions(+), 31 deletions(-) diff --git a/drivers/media/video/gspca/gspca.c b/drivers/media/video/gspca/gspca.c index eac7aec4425..8aac7a1e8f3 100644 --- a/drivers/media/video/gspca/gspca.c +++ b/drivers/media/video/gspca/gspca.c @@ -132,11 +132,13 @@ static void fill_frame(struct gspca_dev *gspca_dev, cam_pkt_op pkt_scan; if (urb->status != 0) { + if (urb->status == -ESHUTDOWN) + return; /* disconnection */ #ifdef CONFIG_PM if (!gspca_dev->frozen) #endif PDEBUG(D_ERR|D_PACK, "urb status: %d", urb->status); - return; /* disconnection ? */ + return; } pkt_scan = gspca_dev->sd_desc->pkt_scan; for (i = 0; i < urb->number_of_packets; i++) { @@ -208,6 +210,8 @@ static void bulk_irq(struct urb *urb) switch (urb->status) { case 0: break; + case -ESHUTDOWN: + return; /* disconnection */ case -ECONNRESET: urb->status = 0; break; @@ -216,7 +220,7 @@ static void bulk_irq(struct urb *urb) if (!gspca_dev->frozen) #endif PDEBUG(D_ERR|D_PACK, "urb status: %d", urb->status); - return; /* disconnection ? */ + return; } /* check the availability of the frame buffer */ @@ -422,10 +426,8 @@ static void destroy_urbs(struct gspca_dev *gspca_dev) if (urb == NULL) break; - BUG_ON(!gspca_dev->dev); gspca_dev->urb[i] = NULL; - if (!gspca_dev->present) - usb_kill_urb(urb); + usb_kill_urb(urb); if (urb->transfer_buffer != NULL) usb_buffer_free(gspca_dev->dev, urb->transfer_buffer_length, @@ -593,6 +595,11 @@ static int gspca_init_transfer(struct gspca_dev *gspca_dev) if (mutex_lock_interruptible(&gspca_dev->usb_lock)) return -ERESTARTSYS; + if (!gspca_dev->present) { + ret = -ENODEV; + goto out; + } + /* set the higher alternate setting and * loop until urb submit succeeds */ gspca_dev->alt = gspca_dev->nbalt; @@ -662,12 +669,14 @@ static int gspca_set_alt0(struct gspca_dev *gspca_dev) static void gspca_stream_off(struct gspca_dev *gspca_dev) { gspca_dev->streaming = 0; - if (gspca_dev->present - && gspca_dev->sd_desc->stopN) - gspca_dev->sd_desc->stopN(gspca_dev); - destroy_urbs(gspca_dev); - if (gspca_dev->present) + if (gspca_dev->present) { + if (gspca_dev->sd_desc->stopN) + gspca_dev->sd_desc->stopN(gspca_dev); + destroy_urbs(gspca_dev); gspca_set_alt0(gspca_dev); + } + + /* always call stop0 to free the subdriver's resources */ if (gspca_dev->sd_desc->stop0) gspca_dev->sd_desc->stop0(gspca_dev); PDEBUG(D_STREAM, "stream off OK"); @@ -949,8 +958,17 @@ static int vidioc_querycap(struct file *file, void *priv, struct v4l2_capability *cap) { struct gspca_dev *gspca_dev = priv; + int ret; memset(cap, 0, sizeof *cap); + + /* protect the access to the usb device */ + if (mutex_lock_interruptible(&gspca_dev->usb_lock)) + return -ERESTARTSYS; + if (!gspca_dev->present) { + ret = -ENODEV; + goto out; + } strncpy(cap->driver, gspca_dev->sd_desc->name, sizeof cap->driver); if (gspca_dev->dev->product != NULL) { strncpy(cap->card, gspca_dev->dev->product, @@ -966,7 +984,10 @@ static int vidioc_querycap(struct file *file, void *priv, cap->capabilities = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING | V4L2_CAP_READWRITE; - return 0; + ret = 0; +out: + mutex_unlock(&gspca_dev->usb_lock); + return ret; } static int vidioc_queryctrl(struct file *file, void *priv, @@ -1029,7 +1050,10 @@ static int vidioc_s_ctrl(struct file *file, void *priv, PDEBUG(D_CONF, "set ctrl [%08x] = %d", ctrl->id, ctrl->value); if (mutex_lock_interruptible(&gspca_dev->usb_lock)) return -ERESTARTSYS; - ret = ctrls->set(gspca_dev, ctrl->value); + if (gspca_dev->present) + ret = ctrls->set(gspca_dev, ctrl->value); + else + ret = -ENODEV; mutex_unlock(&gspca_dev->usb_lock); return ret; } @@ -1053,7 +1077,10 @@ static int vidioc_g_ctrl(struct file *file, void *priv, return -EINVAL; if (mutex_lock_interruptible(&gspca_dev->usb_lock)) return -ERESTARTSYS; - ret = ctrls->get(gspca_dev, &ctrl->value); + if (gspca_dev->present) + ret = ctrls->get(gspca_dev, &ctrl->value); + else + ret = -ENODEV; mutex_unlock(&gspca_dev->usb_lock); return ret; } @@ -1215,10 +1242,7 @@ static int vidioc_streamon(struct file *file, void *priv, return -EINVAL; if (mutex_lock_interruptible(&gspca_dev->queue_lock)) return -ERESTARTSYS; - if (!gspca_dev->present) { - ret = -ENODEV; - goto out; - } + if (gspca_dev->nframes == 0 || !(gspca_dev->frame[0].v4l2_buf.flags & V4L2_BUF_FLAG_QUEUED)) { ret = -EINVAL; @@ -1286,7 +1310,10 @@ static int vidioc_g_jpegcomp(struct file *file, void *priv, return -EINVAL; if (mutex_lock_interruptible(&gspca_dev->usb_lock)) return -ERESTARTSYS; - ret = gspca_dev->sd_desc->get_jcomp(gspca_dev, jpegcomp); + if (gspca_dev->present) + ret = gspca_dev->sd_desc->get_jcomp(gspca_dev, jpegcomp); + else + ret = -ENODEV; mutex_unlock(&gspca_dev->usb_lock); return ret; } @@ -1301,7 +1328,10 @@ static int vidioc_s_jpegcomp(struct file *file, void *priv, return -EINVAL; if (mutex_lock_interruptible(&gspca_dev->usb_lock)) return -ERESTARTSYS; - ret = gspca_dev->sd_desc->set_jcomp(gspca_dev, jpegcomp); + if (gspca_dev->present) + ret = gspca_dev->sd_desc->set_jcomp(gspca_dev, jpegcomp); + else + ret = -ENODEV; mutex_unlock(&gspca_dev->usb_lock); return ret; } @@ -1320,7 +1350,11 @@ static int vidioc_g_parm(struct file *filp, void *priv, if (mutex_lock_interruptible(&gspca_dev->usb_lock)) return -ERESTARTSYS; - ret = gspca_dev->sd_desc->get_streamparm(gspca_dev, parm); + if (gspca_dev->present) + ret = gspca_dev->sd_desc->get_streamparm(gspca_dev, + parm); + else + ret = -ENODEV; mutex_unlock(&gspca_dev->usb_lock); return ret; } @@ -1345,7 +1379,11 @@ static int vidioc_s_parm(struct file *filp, void *priv, if (mutex_lock_interruptible(&gspca_dev->usb_lock)) return -ERESTARTSYS; - ret = gspca_dev->sd_desc->set_streamparm(gspca_dev, parm); + if (gspca_dev->present) + ret = gspca_dev->sd_desc->set_streamparm(gspca_dev, + parm); + else + ret = -ENODEV; mutex_unlock(&gspca_dev->usb_lock); return ret; } @@ -1519,7 +1557,8 @@ static int frame_wait(struct gspca_dev *gspca_dev, if (gspca_dev->sd_desc->dq_callback) { mutex_lock(&gspca_dev->usb_lock); - gspca_dev->sd_desc->dq_callback(gspca_dev); + if (gspca_dev->present) + gspca_dev->sd_desc->dq_callback(gspca_dev); mutex_unlock(&gspca_dev->usb_lock); } return j; @@ -1541,6 +1580,9 @@ static int vidioc_dqbuf(struct file *file, void *priv, if (v4l2_buf->memory != gspca_dev->memory) return -EINVAL; + if (!gspca_dev->present) + return -ENODEV; + /* if not streaming, be sure the application will not loop forever */ if (!(file->f_flags & O_NONBLOCK) && !gspca_dev->streaming && gspca_dev->users == 1) @@ -1691,8 +1733,6 @@ static unsigned int dev_poll(struct file *file, poll_table *wait) PDEBUG(D_FRAM, "poll"); poll_wait(file, &gspca_dev->wq, wait); - if (!gspca_dev->present) - return POLLERR; /* if reqbufs is not done, the user would use read() */ if (gspca_dev->nframes == 0) { @@ -1705,10 +1745,6 @@ static unsigned int dev_poll(struct file *file, poll_table *wait) if (mutex_lock_interruptible(&gspca_dev->queue_lock) != 0) return POLLERR; - if (!gspca_dev->present) { - ret = POLLERR; - goto out; - } /* check the next incoming buffer */ i = gspca_dev->fr_o; @@ -1717,8 +1753,9 @@ static unsigned int dev_poll(struct file *file, poll_table *wait) ret = POLLIN | POLLRDNORM; /* something to read */ else ret = 0; -out: mutex_unlock(&gspca_dev->queue_lock); + if (!gspca_dev->present) + return POLLHUP; return ret; } @@ -1944,10 +1981,16 @@ void gspca_disconnect(struct usb_interface *intf) mutex_lock(&gspca_dev->usb_lock); gspca_dev->present = 0; - mutex_unlock(&gspca_dev->usb_lock); - destroy_urbs(gspca_dev); + if (gspca_dev->streaming) { + destroy_urbs(gspca_dev); + wake_up_interruptible(&gspca_dev->wq); + } + + /* the device is freed at exit of this function */ gspca_dev->dev = NULL; + mutex_unlock(&gspca_dev->usb_lock); + usb_set_intfdata(intf, NULL); /* release the device */ -- 2.39.2