net: Stop leased rxq before uninstalling its memory provider
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: net: Stop leased rxq before uninstalling its memory provider netif_rxq_cleanup_unlease() tears down the memory provider that was installed on a physical RX queue through a netkit queue lease. It currently revokes the provider's DMA mappings before stopping the physical queue: __netif_mp_uninstall_rxq(virt_rxq, p); /* DMA unmap */ __netif_mp_close_rxq(phys_rxq->dev, rxq_idx, p); /* queue stop */ This inverts the ordering used by the regular teardown paths (normal device unregister and the io_uring zcrx close path), which stop the queue before revoking the provider's mappings. With the physical queue still live, its NAPI can keep consuming net_iov entries from the page_pool alloc cache after the __netif_mp_uninstall_rxq() has already cleared their dma_addr, opening a window for the device to DMA to a stale or zero address. Fix it by swapping the two calls so the queue is stopped (and its NAPI quiesced) before the provider is uninstalled. No functional regression was observed across repeated runs of the nk_qlease.py HW selftest, which exercises the lease teardown path; this was tested against fbnic QEMU emulation.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
Version range not reported
- Linux Linux
7.1