{"id":"CVE-2025-40199","revision":"a5e2d031b12442cf9fa4b23f85ed51b1","records":[{"revision":"a5e2d031b12442cf9fa4b23f85ed51b1","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2025-40199","aliases":[],"title":"page_pool: Fix PP_MAGIC_MASK to avoid crashing on some 32-bit arches","description":"In the Linux kernel, the following vulnerability has been resolved:\n\npage_pool: Fix PP_MAGIC_MASK to avoid crashing on some 32-bit arches\n\nHelge reported that the introduction of PP_MAGIC_MASK let to crashes on\nboot on his 32-bit parisc machine. The cause of this is the mask is set\ntoo wide, so the page_pool_page_is_pp() incurs false positives which\ncrashes the machine.\n\nJust disabling the check in page_pool_is_pp() will lead to the page_pool\ncode itself malfunctioning; so instead of doing this, this patch changes\nthe define for PP_DMA_INDEX_BITS to avoid mistaking arbitrary kernel\npointers for page_pool-tagged pages.\n\nThe fix relies on the kernel pointers that alias with the pp_magic field\nalways being above PAGE_OFFSET. With this assumption, we can use the\nlowest bit of the value of PAGE_OFFSET as the upper bound of the\nPP_DMA_INDEX_MASK, which should avoid the false positives.\n\nBecause we cannot rely on PAGE_OFFSET always being a compile-time\nconstant, nor on it always being >0, we fall back to disabling the\ndma_index storage when there are not enough bits available. This leaves\nus in the situation we were in before the patch in the Fixes tag, but\nonly on a subset of architecture configurations. This seems to be the\nbest we can do until the transition to page types in complete for\npage_pool pages.\n\nv2:\n- Make sure there's at least 8 bits available and that the PAGE_OFFSET\n  bit calculation doesn't wrap","state":0,"publishedAt":"2025-11-12T21:56:33.51+00:00","modifiedAt":"2026-10-15T22:02:40.424+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                        \"include/linux/mm.h\",\n                        \"net/core/page_pool.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4f51fb0d257ff4d406ec27966902de075e3b118e\",\n                            \"lessThan\": \"15b8a5b4cdc16e9a8bb2a548e12a0fd92997605a\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"ee62ce7a1d909ccba0399680a03c2dee83bcae95\",\n                            \"lessThan\": \"f62934cea32c8f7b11b747975d69bf5afe4264cf\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"ee62ce7a1d909ccba0399680a03c2dee83bcae95\",\n                            \"lessThan\": \"95920c2ed02bde551ab654e9749c2ca7bc3100e0\",\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\": \"6.12.54\",\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                        \"include/linux/mm.h\",\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\": \"6.12.54\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.17.4\",\n                            \"lessThanOrEqual\": \"6.17.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/15b8a5b4cdc16e9a8bb2a548e12a0fd92997605a","https://git.kernel.org/stable/c/f62934cea32c8f7b11b747975d69bf5afe4264cf","https://git.kernel.org/stable/c/95920c2ed02bde551ab654e9749c2ca7bc3100e0"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-40199","license":"CVE Program Terms of Use","key":"cve-program:CVE-2025-40199","identifiers":["CVE-2025-40199"]},"retained":false,"historicalAffected":[]}],"coverage":[]}