CVE-2023-52492

Dashboard / Vulnerabilities / CVE-2023-52492

CVE-2023-52492

Summary: dmaengine: fix NULL pointer in channel unregistration function

Details: In the Linux kernel, the following vulnerability has been resolved: dmaengine: fix NULL pointer in channel unregistration function __dma_async_device_channel_register() can fail. In case of failure, chan->local is freed (with free_percpu()), and chan->local is nullified. When dma_async_device_unregister() is called (because of managed API or intentionally by DMA controller driver), channels are unconditionally unregistered, leading to this NULL pointer: [ 1.318693] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000d0 [...] [ 1.484499] Call trace: [ 1.486930] device_del+0x40/0x394 [ 1.490314] device_unregister+0x20/0x7c [ 1.494220] __dma_async_device_channel_unregister+0x68/0xc0 Look at dma_async_device_register() function error path, channel device unregistration is done only if chan->local is not NULL. Then add the same condition at the beginning of __dma_async_device_channel_unregister() function, to avoid NULL pointer issue whatever the API used to reach this function.

References: https://git.kernel.org/stable/c/047fce470412ab64cb7345f9ff5d06919078ad79, https://git.kernel.org/stable/c/2ab32986a0b9e329eb7f8f04dd57cc127f797c08, https://git.kernel.org/stable/c/7f0ccfad2031eddcc510caf4e57f2d4aa2d8a50b, https://git.kernel.org/stable/c/9263fd2a63487c6d04cbb7b74a48fb12e1e352d0, https://git.kernel.org/stable/c/9de69732dde4e443c1c7f89acbbed2c45a6a8e17, https://git.kernel.org/stable/c/f5c24d94512f1b288262beda4d3dcb9629222fc7, https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html, https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/52xxx/CVE-2023-52492.json, https://nvd.nist.gov/vuln/detail/CVE-2023-52492, https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git