{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-93233","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-17T16:02:15.095Z","datePublished":"2026-09-24T15:32:51.743Z","dateUpdated":"2026-09-24T15:32:51.743Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-24T15:32:51.743Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/nouveau/dmem: fix callocated underflow on large folio split\n\nnouveau_dmem_folio_free() drops chunk->callocated once per freed folio,\nwhile a large (compound) device-private folio is only counted once when\nit is allocated.  When such a folio is split, the mm core invokes\n->folio_split() (nouveau_dmem_folio_split()) once for each new\nsub-folio, but the hook only fixes up the sub-folio metadata and leaves\nchunk->callocated unchanged.\n\nEach resulting sub-folio is later freed separately, so after a split\nthe single allocation (+1) is met by N frees (-N), leaving\nchunk->callocated short by N-1.  On the first split/free cycle it\nunderflows: WARN_ON(!chunk->callocated) fires, the unsigned counter\nwraps and never returns to zero, so the chunk can no longer be\nreclaimed (nouveau_dmem_fini() also warns on the leaked count).\n\nAccount for the new sub-folio in the split hook, under the same lock as\nnouveau_dmem_folio_free(), so the count stays balanced."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpu/drm/nouveau/nouveau_dmem.c"],"versions":[{"version":"c3228747107705d47c7e9a03598a434a0380cb73","lessThan":"0163b92946d0a7c816f619c57a4d9867954dd106","status":"affected","versionType":"git"},{"version":"c3228747107705d47c7e9a03598a434a0380cb73","lessThan":"c2256c044a1df39c8aad4dd2d6f709b2533e2d7a","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpu/drm/nouveau/nouveau_dmem.c"],"versions":[{"version":"6.19","status":"affected"},{"version":"0","lessThan":"6.19","status":"unaffected","versionType":"semver"},{"version":"7.2.5","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc2","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19","versionEndExcluding":"7.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19","versionEndExcluding":"7.3-rc2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/0163b92946d0a7c816f619c57a4d9867954dd106"},{"url":"https://git.kernel.org/stable/c/c2256c044a1df39c8aad4dd2d6f709b2533e2d7a"}],"title":"drm/nouveau/dmem: fix callocated underflow on large folio split","x_generator":{"engine":"bippy-1.2.0"}}}}