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| author | Shivank Garg <shivankg@amd.com> | 2026-08-22 19:22:05 +0000 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2026-09-09 17:51:44 +0530 |
| commit | e873c74132f0c5f1452816cd9bb26208f0bba1e1 (patch) | |
| tree | cc1ce1567f5b982359331863ebd9da38741f8d2e /drivers/video/fbdev/sbuslib.h | |
| download | linux-stable-e873c74132f0c5f1452816cd9bb26208f0bba1e1.tar.gz linux-stable-e873c74132f0c5f1452816cd9bb26208f0bba1e1.zip | |
dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel()grafted
When dma_device_put() drops the last reference on chan->device->ref,
dma_device_release() runs and may free the dma_device along with its
channels.
dma_chan_put() then still reads chan->device->owner via
dma_chan_to_owner() for the trailing module_put(). KASAN catches it:
slab-use-after-free in dma_chan_put+0x3e6/0x4c0
Read of size 8 by task insmod/6319
Freed by task 6319:
kfree+0x225/0x470
dma_chan_put+0x395/0x4c0
dmaengine_put+0xf8/0x160
Cache the module owner in dma_chan_put() before the put so the trailing
module_put() does not need chan->device.
Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct")
Suggested-by: Sashiko <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/video/fbdev/sbuslib.h')
| -rw-r--r-- | drivers/video/fbdev/sbuslib.h | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/drivers/video/fbdev/sbuslib.h b/drivers/video/fbdev/sbuslib.h new file mode 100644 index 000000000..e9af2dc93 --- /dev/null +++ b/drivers/video/fbdev/sbuslib.h @@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* sbuslib.h: SBUS fb helper library interfaces */ +#ifndef _SBUSLIB_H +#define _SBUSLIB_H + +struct device_node; +struct fb_info; +struct fb_var_screeninfo; +struct vm_area_struct; + +struct sbus_mmap_map { + unsigned long voff; + unsigned long poff; + unsigned long size; +}; + +#define SBUS_MMAP_FBSIZE(n) (-n) +#define SBUS_MMAP_EMPTY 0x80000000 + +extern void sbusfb_fill_var(struct fb_var_screeninfo *var, + struct device_node *dp, int bpp); +extern int sbusfb_mmap_helper(const struct sbus_mmap_map *map, + unsigned long physbase, unsigned long fbsize, + unsigned long iospace, + struct vm_area_struct *vma); +int sbusfb_ioctl_helper(unsigned long cmd, unsigned long arg, + struct fb_info *info, + int type, int fb_depth, unsigned long fb_size); +int sbusfb_compat_ioctl(struct fb_info *info, unsigned int cmd, + unsigned long arg); + +/* + * Initialize struct fb_ops for SBUS I/O. + */ + +#define __FB_DEFAULT_SBUS_OPS_RDWR(__prefix) \ + .fb_read = fb_io_read, \ + .fb_write = fb_io_write + +#define __FB_DEFAULT_SBUS_OPS_DRAW(__prefix) \ + .fb_fillrect = cfb_fillrect, \ + .fb_copyarea = cfb_copyarea, \ + .fb_imageblit = cfb_imageblit + +#ifdef CONFIG_COMPAT +#define __FB_DEFAULT_SBUS_OPS_IOCTL(__prefix) \ + .fb_ioctl = __prefix ## _sbusfb_ioctl, \ + .fb_compat_ioctl = sbusfb_compat_ioctl +#else +#define __FB_DEFAULT_SBUS_OPS_IOCTL(__prefix) \ + .fb_ioctl = __prefix ## _sbusfb_ioctl +#endif + +#define __FB_DEFAULT_SBUS_OPS_MMAP(__prefix) \ + .fb_mmap = __prefix ## _sbusfb_mmap + +#define FB_DEFAULT_SBUS_OPS(__prefix) \ + __FB_DEFAULT_SBUS_OPS_RDWR(__prefix), \ + __FB_DEFAULT_SBUS_OPS_DRAW(__prefix), \ + __FB_DEFAULT_SBUS_OPS_IOCTL(__prefix), \ + __FB_DEFAULT_SBUS_OPS_MMAP(__prefix) + +#endif /* _SBUSLIB_H */ |