From: Tomi Valkeinen tomi.valkeinen@ti.com
commit 0d9668721311607353d4861e6c32afeb272813dc upstream.
Commit 9495b7e92f716ab2bd6814fab5e97ab4a39adfdd ("driver core: platform: Initialize dma_parms for platform devices") in v5.7-rc5 causes vb2_dma_contig_clear_max_seg_size() to kfree memory that was not allocated by vb2_dma_contig_set_max_seg_size().
The assumption in vb2_dma_contig_set_max_seg_size() seems to be that dev->dma_parms is always NULL when the driver is probed, and the case where dev->dma_parms has bee initialized by someone else than the driver (by calling vb2_dma_contig_set_max_seg_size) will cause a failure.
All the current users of these functions are platform devices, which now always have dma_parms set by the driver core. To fix the issue for v5.7, make vb2_dma_contig_set_max_seg_size() return an error if dma_parms is NULL to be on the safe side, and remove the kfree code from vb2_dma_contig_clear_max_seg_size().
For v5.8 we should remove the two functions and move the dma_set_max_seg_size() calls into the drivers.
Signed-off-by: Tomi Valkeinen tomi.valkeinen@ti.com Fixes: 9495b7e92f71 ("driver core: platform: Initialize dma_parms for platform devices") Cc: stable@vger.kernel.org Acked-by: Marek Szyprowski m.szyprowski@samsung.com Reviewed-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Mauro Carvalho Chehab mchehab+huawei@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/media/common/videobuf2/videobuf2-dma-contig.c | 20 +----------------- include/media/videobuf2-dma-contig.h | 2 - 2 files changed, 3 insertions(+), 19 deletions(-)
--- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c +++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c @@ -726,9 +726,8 @@ EXPORT_SYMBOL_GPL(vb2_dma_contig_memops) int vb2_dma_contig_set_max_seg_size(struct device *dev, unsigned int size) { if (!dev->dma_parms) { - dev->dma_parms = kzalloc(sizeof(*dev->dma_parms), GFP_KERNEL); - if (!dev->dma_parms) - return -ENOMEM; + dev_err(dev, "Failed to set max_seg_size: dma_parms is NULL\n"); + return -ENODEV; } if (dma_get_max_seg_size(dev) < size) return dma_set_max_seg_size(dev, size); @@ -737,21 +736,6 @@ int vb2_dma_contig_set_max_seg_size(stru } EXPORT_SYMBOL_GPL(vb2_dma_contig_set_max_seg_size);
-/* - * vb2_dma_contig_clear_max_seg_size() - release resources for DMA parameters - * @dev: device for configuring DMA parameters - * - * This function releases resources allocated to configure DMA parameters - * (see vb2_dma_contig_set_max_seg_size() function). It should be called from - * device drivers on driver remove. - */ -void vb2_dma_contig_clear_max_seg_size(struct device *dev) -{ - kfree(dev->dma_parms); - dev->dma_parms = NULL; -} -EXPORT_SYMBOL_GPL(vb2_dma_contig_clear_max_seg_size); - MODULE_DESCRIPTION("DMA-contig memory handling routines for videobuf2"); MODULE_AUTHOR("Pawel Osciak pawel@osciak.com"); MODULE_LICENSE("GPL"); --- a/include/media/videobuf2-dma-contig.h +++ b/include/media/videobuf2-dma-contig.h @@ -25,7 +25,7 @@ vb2_dma_contig_plane_dma_addr(struct vb2 }
int vb2_dma_contig_set_max_seg_size(struct device *dev, unsigned int size); -void vb2_dma_contig_clear_max_seg_size(struct device *dev); +static inline void vb2_dma_contig_clear_max_seg_size(struct device *dev) { }
extern const struct vb2_mem_ops vb2_dma_contig_memops;