CVE-2026-74654
In the Linux kernel, the following vulnerability has been resolved: serial: 8250_dma: Clear stale RX state on shutdown serial8250_release_dma() terminates RX DMA and releases the channel, but leaves rx_running set.
Does this matter?
Not yet scored. NVD analysis is pending; check back once CVSS and EPSS values are published.
Description
In the Linux kernel, the following vulnerability has been resolved: serial: 8250_dma: Clear stale RX state on shutdown serial8250_release_dma() terminates RX DMA and releases the channel, but leaves rx_running set. If the port is closed while an RX transfer is active, the stale state remains while rxchan is NULL until the channel is requested again on the next open. The DesignWare BUSY workaround added by commit a7b9ce39fbe4 ("serial: 8250_dw: Ensure BUSY is deasserted") calls serial8250_rx_dma_flush() from the LCR write path during startup. This happens before serial8250_request_dma() obtains a new RX channel. On reopen, the stale rx_running state therefore makes the flush path pass a NULL channel to dmaengine_pause(), causing a kernel Oops. Clear rx_running after terminating RX DMA, matching the TX cleanup. Also make the flush helper return if the DMA object or RX channel is not available so startup and teardown paths cannot pass a NULL channel to the DMAengine API.
- CVSS
- Not yet scored
- EPSS
- 0.18% probability · 7th percentile
- CISA KEV
- Not listed
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/9f2444f4c0e4b06f61bae38da87c9c94c78efa86
- https://git.kernel.org/stable/c/ae05d9e50b6b9f246c110b3bdc03676145c2d0d4
- https://git.kernel.org/stable/c/bf4fb620e02962b2b52500a4b3d8420f351eb46a
- https://git.kernel.org/stable/c/d06cfb1add4a2d5b393e9e31f49ebbd168beea49
- https://git.kernel.org/stable/c/e10f06ee050a08930e2339b6fec7148fd0b2a8f6
- https://git.kernel.org/stable/c/e2fe6a0efecbef00e3ecc2db64dd5afa8c212b41
- https://git.kernel.org/stable/c/e7a5d792cf64a2096e18f1d573cc3d01cba15e92
- https://git.kernel.org/stable/c/e7e3cc6709caa49d1d6ce6c1f7cb305e38675cc9
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.