{"id":"CVE-2026-90201","revision":"765fbe757eeb442495983455e62a0570","records":[{"revision":"765fbe757eeb442495983455e62a0570","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-90201","aliases":[],"title":"net: page_pool: fix UAF in __page_pool_release_netmem_dma on xa_cmpxchg race","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: page_pool: fix UAF in __page_pool_release_netmem_dma on xa_cmpxchg race\n\nThis bug was discovered while testing the hns3 driver under channel\nreconfiguration (`ethtool -L` / `ethtool -G`) with iperf3 traffic on\narm64. The race is intermittently triggered when page_pool_destroy()\nruns page_pool_scrub() concurrently with page return via\npage_pool_put_netmem() on a different CPU. A WARN in\npage_pool_clear_pp_info() surfaced the dangling DMA index bits left\nby the cmpxchg loser, which led to the investigation.\n\npage_pool_scrub() iterates pool->dma_mapped via xa_for_each() with no\npage ref held. __page_pool_release_netmem_dma() currently reads and\nwrites netmem fields (dma_addr, DMA index bits in pp_magic) after\nxa_cmpxchg() returns. The unref path calls put_page() unconditionally\nregardless of the cmpxchg outcome; when it loses the cmpxchg, it still\nfrees the page before the scrub winner finishes these netmem accesses,\nso scrub touches a freed page -- a Use-After-Free.\n\nFix this by splitting the DMA release into two functions:\n\n1. __page_pool_unmap_netmem_dma() caches dma_addr before xa_cmpxchg(),\n   does the cmpxchg to remove the DMA mapping, and calls dma_unmap on\n   the cached address. It never touches netmem fields after the cmpxchg,\n   making it safe for the scrub path which holds no page ref.\n\n2. __page_pool_release_netmem_dma() wraps the above and additionally\n   clears dma_addr and DMA index bits in netmem fields. This is safe\n   only when the caller holds a page ref, so it is used by the return\n   path (page_pool_return_netmem).\n\nThe scrub path calls __page_pool_unmap_netmem_dma() directly; the return\npath calls __page_pool_release_netmem_dma().","state":0,"publishedAt":"2026-09-17T16:07:18.838+00:00","modifiedAt":"2026-10-19T08:59:37.392+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/core/page_pool.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4f51fb0d257ff4d406ec27966902de075e3b118e\",\n                            \"lessThan\": \"bbfef303f980c1c078b8fa142e10a0e2fbcdd247\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"ee62ce7a1d909ccba0399680a03c2dee83bcae95\",\n                            \"lessThan\": \"424a9fc4876cc7f28e9cb0aa8d92e920d726e350\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"ee62ce7a1d909ccba0399680a03c2dee83bcae95\",\n                            \"lessThan\": \"9b65b0253ad5a66f73efee9a79a21a1e2b57cf59\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"ee62ce7a1d909ccba0399680a03c2dee83bcae95\",\n                            \"lessThan\": \"24ef02f934eeb48830cff6b739abc3c62b1d107b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c30ae60f41f9edd6e1b5cad41cf28ce04dae39e4\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"6.12.34\",\n                            \"lessThan\": \"6.12.110\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.15.3\",\n                            \"lessThan\": \"6.16\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/core/page_pool.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.16\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.16\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.110\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.52\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.6\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/bbfef303f980c1c078b8fa142e10a0e2fbcdd247","https://git.kernel.org/stable/c/424a9fc4876cc7f28e9cb0aa8d92e920d726e350","https://git.kernel.org/stable/c/9b65b0253ad5a66f73efee9a79a21a1e2b57cf59","https://git.kernel.org/stable/c/24ef02f934eeb48830cff6b739abc3c62b1d107b"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-90201","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-90201","identifiers":["CVE-2026-90201"]},"retained":false,"historicalAffected":[]}],"coverage":[]}