Specifically, I think the three malicious patches described in the paper are:
- UAF case 1, Fig. 11 => crypto: cavium/nitrox: add an error message to explain the failure of pci_request_mem_regions, https://lore.kernel.org/lkml/20200821031209.21279-1-acostag.... The day after this patch was merged into a driver tree, the author suggested calling dev_err() before pci_disable_device(), which presumably was their attempt at maintainer notification; however, the code as merged doesn't actually appear to constitute a vulnerability because pci_disable_device() doesn't appear to free the struct pci_dev.
- UAF case 2, Fig. 9 => tty/vt: fix a memory leak in con_insert_unipair, https://lore.kernel.org/lkml/20200809221453.10235-1-jameslou... This patch was not accepted.
- UAF case 3, Fig. 10 => rapidio: fix get device imbalance on error, https://lore.kernel.org/lkml/20200821034458.22472-1-acostag.... Same author as case 1. This patch was not accepted.
This is not to say that open-source security is not a concern, but IMO the paper is deliberately misleading in an attempt to overstate its contributions.
edit: wording tweak for clarity