Description
In the Linux kernel, the following vulnerability has been resolved: serial: 8250: Fix TX deadlock when using DMA `dmaengine_terminate_async` does not guarantee that the `__dma_tx_complete` callback will run. The callback is currently the only place where `dma->tx_running` gets cleared. If the transaction is canceled and the callback never runs, then `dma->tx_running` will never get cleared and we will never schedule new TX DMA transactions again. This change makes it so we clear `dma->tx_running` after we terminate the DMA transaction. This is "safe" because `serial8250_tx_dma_flush` is holding the UART port lock. The first thing the callback does is also grab the UART port lock, so access to `dma->tx_running` is serialized.
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/2a72403b985aea6b4aac3171830492f9a387f9e1 Patch
- git.kernel.org/stable/c/5f6b17562f03fc65c7d3474ef8f1959b19d1ca41 Patch
- git.kernel.org/stable/c/79a19bd936bb35f56ef0ccab1b3b59ebce8c762d Patch
- git.kernel.org/stable/c/8190f9ab6ad90cb97652adbebd238b874a4ef70d Patch
- git.kernel.org/stable/c/a424a34b8faddf97b5af41689087e7a230f79ba7 Patch
- git.kernel.org/stable/c/b5ad887339503103d0fbe9827b16ad287597c275 Patch
- git.kernel.org/stable/c/d2719a0a9c3439abf67843a5504b7afccd9ded93 Patch
- git.kernel.org/stable/c/f76d91271bcacbd759a2e4ee3ea61faa6a727ccf Patch
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 0 · as of 13 November 2026
- CWE
- CWE-667
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