From 33e3c349b2bf1235be458df09fb8d237141486c4 Mon Sep 17 00:00:00 2001 From: Bingbu Cao Date: Thu, 26 Mar 2020 15:54:37 +0100 Subject: [PATCH] media: staging/intel-ipu3: Implement lock for stream on/off operations Currently concurrent stream off operations on ImgU nodes are not synchronized, leading to use-after-free bugs (as reported by KASAN). [ 250.090724] BUG: KASAN: use-after-free in ipu3_dmamap_free+0xc5/0x116 [ipu3_imgu] [ 250.090726] Read of size 8 at addr ffff888127b29bc0 by task yavta/18836 [ 250.090731] Hardware name: HP Soraka/Soraka, BIOS Google_Soraka.10431.17.0 03/22/2018 [ 250.090732] Call Trace: [ 250.090735] dump_stack+0x6a/0xb1 [ 250.090739] print_address_description+0x8e/0x279 [ 250.090743] ? ipu3_dmamap_free+0xc5/0x116 [ipu3_imgu] [ 250.090746] kasan_report+0x260/0x28a [ 250.090750] ipu3_dmamap_free+0xc5/0x116 [ipu3_imgu] [ 250.090754] ipu3_css_pool_cleanup+0x24/0x37 [ipu3_imgu] [ 250.090759] ipu3_css_pipeline_cleanup+0x61/0xb9 [ipu3_imgu] [ 250.090763] ipu3_css_stop_streaming+0x1f2/0x321 [ipu3_imgu] [ 250.090768] imgu_s_stream+0x94/0x443 [ipu3_imgu] [ 250.090772] ? ipu3_vb2_buf_queue+0x280/0x280 [ipu3_imgu] [ 250.090775] ? vb2_dma_sg_unmap_dmabuf+0x16/0x6f [videobuf2_dma_sg] [ 250.090778] ? vb2_buffer_in_use+0x36/0x58 [videobuf2_common] [ 250.090782] ipu3_vb2_stop_streaming+0xf9/0x135 [ipu3_imgu] Implemented a lock to synchronize imgu stream on / off operations and the modification of streaming flag (in struct imgu_device), to prevent these issues. Reported-by: Laurent Pinchart Suggested-by: Laurent Pinchart Signed-off-by: Rajmohan Mani Signed-off-by: Bingbu Cao Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- drivers/staging/media/ipu3/ipu3-v4l2.c | 10 ++++++++++ drivers/staging/media/ipu3/ipu3.c | 3 +++ drivers/staging/media/ipu3/ipu3.h | 4 ++++ 3 files changed, 17 insertions(+) diff --git a/drivers/staging/media/ipu3/ipu3-v4l2.c b/drivers/staging/media/ipu3/ipu3-v4l2.c index 09c8ede1457c..db8b5d13631a 100644 --- a/drivers/staging/media/ipu3/ipu3-v4l2.c +++ b/drivers/staging/media/ipu3/ipu3-v4l2.c @@ -367,8 +367,10 @@ static void imgu_vb2_buf_queue(struct vb2_buffer *vb) vb2_set_plane_payload(vb, 0, need_bytes); + mutex_lock(&imgu->streaming_lock); if (imgu->streaming) imgu_queue_buffers(imgu, false, node->pipe); + mutex_unlock(&imgu->streaming_lock); dev_dbg(&imgu->pci_dev->dev, "%s for pipe %u node %u", __func__, node->pipe, node->id); @@ -468,10 +470,13 @@ static int imgu_vb2_start_streaming(struct vb2_queue *vq, unsigned int count) dev_dbg(dev, "%s node name %s pipe %u id %u", __func__, node->name, node->pipe, node->id); + mutex_lock(&imgu->streaming_lock); if (imgu->streaming) { r = -EBUSY; + mutex_unlock(&imgu->streaming_lock); goto fail_return_bufs; } + mutex_unlock(&imgu->streaming_lock); if (!node->enabled) { dev_err(dev, "IMGU node is not enabled"); @@ -498,9 +503,11 @@ static int imgu_vb2_start_streaming(struct vb2_queue *vq, unsigned int count) /* Start streaming of the whole pipeline now */ dev_dbg(dev, "IMGU streaming is ready to start"); + mutex_lock(&imgu->streaming_lock); r = imgu_s_stream(imgu, true); if (!r) imgu->streaming = true; + mutex_unlock(&imgu->streaming_lock); return 0; @@ -532,6 +539,7 @@ static void imgu_vb2_stop_streaming(struct vb2_queue *vq) dev_err(&imgu->pci_dev->dev, "failed to stop subdev streaming\n"); + mutex_lock(&imgu->streaming_lock); /* Was this the first node with streaming disabled? */ if (imgu->streaming && imgu_all_nodes_streaming(imgu, node)) { /* Yes, really stop streaming now */ @@ -542,6 +550,8 @@ static void imgu_vb2_stop_streaming(struct vb2_queue *vq) } imgu_return_all_buffers(imgu, node, VB2_BUF_STATE_ERROR); + mutex_unlock(&imgu->streaming_lock); + media_pipeline_stop(&node->vdev.entity); } diff --git a/drivers/staging/media/ipu3/ipu3.c b/drivers/staging/media/ipu3/ipu3.c index 4d53aad31483..a25a997cfd7e 100644 --- a/drivers/staging/media/ipu3/ipu3.c +++ b/drivers/staging/media/ipu3/ipu3.c @@ -675,6 +675,7 @@ static int imgu_pci_probe(struct pci_dev *pci_dev, return r; mutex_init(&imgu->lock); + mutex_init(&imgu->streaming_lock); atomic_set(&imgu->qbuf_barrier, 0); init_waitqueue_head(&imgu->buf_drain_wq); @@ -738,6 +739,7 @@ out_mmu_exit: out_css_powerdown: imgu_css_set_powerdown(&pci_dev->dev, imgu->base); out_mutex_destroy: + mutex_destroy(&imgu->streaming_lock); mutex_destroy(&imgu->lock); return r; @@ -755,6 +757,7 @@ static void imgu_pci_remove(struct pci_dev *pci_dev) imgu_css_set_powerdown(&pci_dev->dev, imgu->base); imgu_dmamap_exit(imgu); imgu_mmu_exit(imgu->mmu); + mutex_destroy(&imgu->streaming_lock); mutex_destroy(&imgu->lock); } diff --git a/drivers/staging/media/ipu3/ipu3.h b/drivers/staging/media/ipu3/ipu3.h index 73b123b2b8a2..8cd6a0077d99 100644 --- a/drivers/staging/media/ipu3/ipu3.h +++ b/drivers/staging/media/ipu3/ipu3.h @@ -146,6 +146,10 @@ struct imgu_device { * vid_buf.list and css->queue */ struct mutex lock; + + /* Lock to protect writes to streaming flag in this struct */ + struct mutex streaming_lock; + /* Forbid streaming and buffer queuing during system suspend. */ atomic_t qbuf_barrier; /* Indicate if system suspend take place while imgu is streaming. */ -- 2.11.0