In the Linux kernel, the following vulnerability has been resolved:
dmaengine: Fix possible use after free
In dma_release_channel(), check chan->device->privatecnt after call dma_chan_put(). However, dma_chan_put() call dma_device_put() which could release the last reference of the device if the DMA provider is already gone and hence free it.
Fixes it by moving dma_chan_put() after the check.
References
- https://git.kernel.org/stable/c/0bc191050c3253da8ef4bfaf157c44efed6e22cd
- https://git.kernel.org/stable/c/329ec20a86091d2a6e5b4fe507545e7d678a22a2
- https://git.kernel.org/stable/c/3b0240483dc977dbec4f3bc7a5383d4691ecb625
- https://git.kernel.org/stable/c/444f96066937f3fdf0e79b53289cff223c7d638b
- https://git.kernel.org/stable/c/5876f38b67a309c00628942cb25679749b53b397
- https://git.kernel.org/stable/c/92f853f0645aebf1d05d333e97ab7c342ace1892
- https://git.kernel.org/stable/c/9bdc8dce4068dadbdf7cf5ad6d4983e2afffedce
- https://git.kernel.org/stable/c/ab438a9efb9042c79d2f8db28a326d55feb8591f