From: Hans Verkuil Date: Wed, 27 Jan 2016 12:08:42 +0000 (-0200) Subject: [media] vb2: fix nasty vb2_thread regression X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=fac710e45d0b12443acd4d905c9acec27ab4ca14;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git [media] vb2: fix nasty vb2_thread regression The vb2_thread implementation was made generic and was moved from videobuf2-v4l2.c to videobuf2-core.c in commit af3bac1a. Unfortunately that clearly was never tested since it broke read() causing NULL address references. The root cause was confused handling of vb2_buffer vs v4l2_buffer (the pb pointer in various core functions). The v4l2_buffer no longer exists after moving the code into the core and it is no longer needed. However, the vb2_thread code passed a pointer to a vb2_buffer to the core functions were a v4l2_buffer pointer was expected and vb2_thread expected that the vb2_buffer fields would be filled in correctly. This is obviously wrong since v4l2_buffer != vb2_buffer. Note that the pb pointer is a void pointer, so no type-checking took place. This patch fixes this problem: 1) allow pb to be NULL for vb2_core_(d)qbuf. The vb2_thread code will use a NULL pointer here since they don't care about v4l2_buffer anyway. 2) let vb2_core_dqbuf pass back the index of the received buffer. This is all vb2_thread needs: this index is the index into the q->bufs array and vb2_thread just gets the vb2_buffer from there. 3) the fileio->b pointer (that originally contained a v4l2_buffer) is removed altogether since it is no longer needed. Tested with vivid and the cobalt driver. Cc: stable@vger.kernel.org # Kernel >= 4.3 Signed-off-by: Hans Verkuil Reported-by: Matthias Schwarzott Signed-off-by: Mauro Carvalho Chehab --- diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c index c5d49d7a0d76..b53e42c329cb 100644 --- a/drivers/media/v4l2-core/videobuf2-core.c +++ b/drivers/media/v4l2-core/videobuf2-core.c @@ -1063,8 +1063,11 @@ EXPORT_SYMBOL_GPL(vb2_discard_done); */ static int __qbuf_mmap(struct vb2_buffer *vb, const void *pb) { - int ret = call_bufop(vb->vb2_queue, fill_vb2_buffer, - vb, pb, vb->planes); + int ret = 0; + + if (pb) + ret = call_bufop(vb->vb2_queue, fill_vb2_buffer, + vb, pb, vb->planes); return ret ? ret : call_vb_qop(vb, buf_prepare, vb); } @@ -1077,14 +1080,16 @@ static int __qbuf_userptr(struct vb2_buffer *vb, const void *pb) struct vb2_queue *q = vb->vb2_queue; void *mem_priv; unsigned int plane; - int ret; + int ret = 0; enum dma_data_direction dma_dir = q->is_output ? DMA_TO_DEVICE : DMA_FROM_DEVICE; bool reacquired = vb->planes[0].mem_priv == NULL; memset(planes, 0, sizeof(planes[0]) * vb->num_planes); /* Copy relevant information provided by the userspace */ - ret = call_bufop(vb->vb2_queue, fill_vb2_buffer, vb, pb, planes); + if (pb) + ret = call_bufop(vb->vb2_queue, fill_vb2_buffer, + vb, pb, planes); if (ret) return ret; @@ -1192,14 +1197,16 @@ static int __qbuf_dmabuf(struct vb2_buffer *vb, const void *pb) struct vb2_queue *q = vb->vb2_queue; void *mem_priv; unsigned int plane; - int ret; + int ret = 0; enum dma_data_direction dma_dir = q->is_output ? DMA_TO_DEVICE : DMA_FROM_DEVICE; bool reacquired = vb->planes[0].mem_priv == NULL; memset(planes, 0, sizeof(planes[0]) * vb->num_planes); /* Copy relevant information provided by the userspace */ - ret = call_bufop(vb->vb2_queue, fill_vb2_buffer, vb, pb, planes); + if (pb) + ret = call_bufop(vb->vb2_queue, fill_vb2_buffer, + vb, pb, planes); if (ret) return ret; @@ -1520,7 +1527,8 @@ int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb) q->waiting_for_buffers = false; vb->state = VB2_BUF_STATE_QUEUED; - call_void_bufop(q, copy_timestamp, vb, pb); + if (pb) + call_void_bufop(q, copy_timestamp, vb, pb); trace_vb2_qbuf(q, vb); @@ -1532,7 +1540,8 @@ int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb) __enqueue_in_driver(vb); /* Fill buffer information for the userspace */ - call_void_bufop(q, fill_user_buffer, vb, pb); + if (pb) + call_void_bufop(q, fill_user_buffer, vb, pb); /* * If streamon has been called, and we haven't yet called @@ -1731,7 +1740,8 @@ static void __vb2_dqbuf(struct vb2_buffer *vb) * The return values from this function are intended to be directly returned * from vidioc_dqbuf handler in driver. */ -int vb2_core_dqbuf(struct vb2_queue *q, void *pb, bool nonblocking) +int vb2_core_dqbuf(struct vb2_queue *q, unsigned int *pindex, void *pb, + bool nonblocking) { struct vb2_buffer *vb = NULL; int ret; @@ -1754,8 +1764,12 @@ int vb2_core_dqbuf(struct vb2_queue *q, void *pb, bool nonblocking) call_void_vb_qop(vb, buf_finish, vb); + if (pindex) + *pindex = vb->index; + /* Fill buffer information for the userspace */ - call_void_bufop(q, fill_user_buffer, vb, pb); + if (pb) + call_void_bufop(q, fill_user_buffer, vb, pb); /* Remove from videobuf queue */ list_del(&vb->queued_entry); @@ -1828,7 +1842,7 @@ static void __vb2_queue_cancel(struct vb2_queue *q) * that's done in dqbuf, but that's not going to happen when we * cancel the whole queue. Note: this code belongs here, not in * __vb2_dqbuf() since in vb2_internal_dqbuf() there is a critical - * call to __fill_v4l2_buffer() after buf_finish(). That order can't + * call to __fill_user_buffer() after buf_finish(). That order can't * be changed, so we can't move the buf_finish() to __vb2_dqbuf(). */ for (i = 0; i < q->num_buffers; ++i) { @@ -2357,7 +2371,6 @@ struct vb2_fileio_data { unsigned int count; unsigned int type; unsigned int memory; - struct vb2_buffer *b; struct vb2_fileio_buf bufs[VB2_MAX_FRAME]; unsigned int cur_index; unsigned int initial_index; @@ -2410,12 +2423,6 @@ static int __vb2_init_fileio(struct vb2_queue *q, int read) if (fileio == NULL) return -ENOMEM; - fileio->b = kzalloc(q->buf_struct_size, GFP_KERNEL); - if (fileio->b == NULL) { - kfree(fileio); - return -ENOMEM; - } - fileio->read_once = q->fileio_read_once; fileio->write_immediately = q->fileio_write_immediately; @@ -2460,13 +2467,7 @@ static int __vb2_init_fileio(struct vb2_queue *q, int read) * Queue all buffers. */ for (i = 0; i < q->num_buffers; i++) { - struct vb2_buffer *b = fileio->b; - - memset(b, 0, q->buf_struct_size); - b->type = q->type; - b->memory = q->memory; - b->index = i; - ret = vb2_core_qbuf(q, i, b); + ret = vb2_core_qbuf(q, i, NULL); if (ret) goto err_reqbufs; fileio->bufs[i].queued = 1; @@ -2511,7 +2512,6 @@ static int __vb2_cleanup_fileio(struct vb2_queue *q) q->fileio = NULL; fileio->count = 0; vb2_core_reqbufs(q, fileio->memory, &fileio->count); - kfree(fileio->b); kfree(fileio); dprintk(3, "file io emulator closed\n"); } @@ -2539,7 +2539,8 @@ static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_ * else is able to provide this information with the write() operation. */ bool copy_timestamp = !read && q->copy_timestamp; - int ret, index; + unsigned index; + int ret; dprintk(3, "mode %s, offset %ld, count %zd, %sblocking\n", read ? "read" : "write", (long)*ppos, count, @@ -2564,22 +2565,20 @@ static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_ */ index = fileio->cur_index; if (index >= q->num_buffers) { - struct vb2_buffer *b = fileio->b; + struct vb2_buffer *b; /* * Call vb2_dqbuf to get buffer back. */ - memset(b, 0, q->buf_struct_size); - b->type = q->type; - b->memory = q->memory; - ret = vb2_core_dqbuf(q, b, nonblock); + ret = vb2_core_dqbuf(q, &index, NULL, nonblock); dprintk(5, "vb2_dqbuf result: %d\n", ret); if (ret) return ret; fileio->dq_count += 1; - fileio->cur_index = index = b->index; + fileio->cur_index = index; buf = &fileio->bufs[index]; + b = q->bufs[index]; /* * Get number of bytes filled by the driver @@ -2630,7 +2629,7 @@ static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_ * Queue next buffer if required. */ if (buf->pos == buf->size || (!read && fileio->write_immediately)) { - struct vb2_buffer *b = fileio->b; + struct vb2_buffer *b = q->bufs[index]; /* * Check if this is the last buffer to read. @@ -2643,15 +2642,11 @@ static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_ /* * Call vb2_qbuf and give buffer to the driver. */ - memset(b, 0, q->buf_struct_size); - b->type = q->type; - b->memory = q->memory; - b->index = index; b->planes[0].bytesused = buf->pos; if (copy_timestamp) b->timestamp = ktime_get_ns(); - ret = vb2_core_qbuf(q, index, b); + ret = vb2_core_qbuf(q, index, NULL); dprintk(5, "vb2_dbuf result: %d\n", ret); if (ret) return ret; @@ -2713,10 +2708,9 @@ static int vb2_thread(void *data) { struct vb2_queue *q = data; struct vb2_threadio_data *threadio = q->threadio; - struct vb2_fileio_data *fileio = q->fileio; bool copy_timestamp = false; - int prequeue = 0; - int index = 0; + unsigned prequeue = 0; + unsigned index = 0; int ret = 0; if (q->is_output) { @@ -2728,37 +2722,34 @@ static int vb2_thread(void *data) for (;;) { struct vb2_buffer *vb; - struct vb2_buffer *b = fileio->b; /* * Call vb2_dqbuf to get buffer back. */ - memset(b, 0, q->buf_struct_size); - b->type = q->type; - b->memory = q->memory; if (prequeue) { - b->index = index++; + vb = q->bufs[index++]; prequeue--; } else { call_void_qop(q, wait_finish, q); if (!threadio->stop) - ret = vb2_core_dqbuf(q, b, 0); + ret = vb2_core_dqbuf(q, &index, NULL, 0); call_void_qop(q, wait_prepare, q); dprintk(5, "file io: vb2_dqbuf result: %d\n", ret); + if (!ret) + vb = q->bufs[index]; } if (ret || threadio->stop) break; try_to_freeze(); - vb = q->bufs[b->index]; - if (b->state == VB2_BUF_STATE_DONE) + if (vb->state == VB2_BUF_STATE_DONE) if (threadio->fnc(vb, threadio->priv)) break; call_void_qop(q, wait_finish, q); if (copy_timestamp) - b->timestamp = ktime_get_ns();; + vb->timestamp = ktime_get_ns();; if (!threadio->stop) - ret = vb2_core_qbuf(q, b->index, b); + ret = vb2_core_qbuf(q, vb->index, NULL); call_void_qop(q, wait_prepare, q); if (ret || threadio->stop) break; diff --git a/drivers/media/v4l2-core/videobuf2-v4l2.c b/drivers/media/v4l2-core/videobuf2-v4l2.c index c9a28605511a..91f552124050 100644 --- a/drivers/media/v4l2-core/videobuf2-v4l2.c +++ b/drivers/media/v4l2-core/videobuf2-v4l2.c @@ -625,7 +625,7 @@ static int vb2_internal_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, return -EINVAL; } - ret = vb2_core_dqbuf(q, b, nonblocking); + ret = vb2_core_dqbuf(q, NULL, b, nonblocking); return ret; } diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index ef03ae56b1c1..8a0f55b6c2ba 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -533,7 +533,8 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, const unsigned int requested_sizes[]); int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb); int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb); -int vb2_core_dqbuf(struct vb2_queue *q, void *pb, bool nonblocking); +int vb2_core_dqbuf(struct vb2_queue *q, unsigned int *pindex, void *pb, + bool nonblocking); int vb2_core_streamon(struct vb2_queue *q, unsigned int type); int vb2_core_streamoff(struct vb2_queue *q, unsigned int type);