{"schema":"threatline.record/2","record":{"id":"CVE-2026-98344","aliases":[],"summary":"dmaengine: Fix device kref underflow in dma_chan_put()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ndmaengine: Fix device kref underflow in dma_chan_put()\n\ndma_chan_get() takes chan->device->ref only on the slow path:\n\n\t/* no kref on fast path */\n\tif (chan->client_count) {\n\t\t__module_get(owner);\n\t\tchan->client_count++;\n\t\treturn 0;\n\t}\n\tif (!try_module_get(owner))\n\t\treturn -ENODEV;\n\tif (!dma_device_get(chan->device)) { // calls kref_get_unless_zero()\n\ndma_chan_put() drops the ref unconditionally, so every fast-path\nget/put pair drops one extra device reference.\n\nThe bug fires when two conditions hold together: a non-private\nprovider has a persistent client holding chan->client_count > 0\nand another client cycles dmaengine_get()/dmaengine_put().\nWhen the kref hits zero, the subsequent dma_find_channel() returns\nNULL even though the provider module is still loaded.\n\nFix this by dropping device->ref only on the last put, matching the\nsingle slow-path get.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98344","source_modified_at":"2026-10-19T09:17:55.263Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"8ad342a863590b24ce77681b7e081363fb3333f7","lessThan":"036b527f92570206da4b8c40b38f8d689e29d0f3","status":"affected","versionType":"git"},{"version":"8ad342a863590b24ce77681b7e081363fb3333f7","lessThan":"5fb1797a8c9485e40e5492fa0338ab5c7d1f3fef","status":"affected","versionType":"git"},{"version":"8ad342a863590b24ce77681b7e081363fb3333f7","lessThan":"57f7f1c6827be7d8f80feca48d2125fb91c6f6ed","status":"affected","versionType":"git"},{"version":"8ad342a863590b24ce77681b7e081363fb3333f7","lessThan":"7c3f4ce651d43705f9ec7f778f642a90d5ff4fba","status":"affected","versionType":"git"},{"version":"8ad342a863590b24ce77681b7e081363fb3333f7","lessThan":"de2677e57d3161390d8a508f08cddec6ef7e4b23","status":"affected","versionType":"git"},{"version":"8ad342a863590b24ce77681b7e081363fb3333f7","lessThan":"1a0d9b406febf23054ad595fd47b29325e70fb2d","status":"affected","versionType":"git"},{"version":"8ad342a863590b24ce77681b7e081363fb3333f7","lessThan":"77906ac448d2fa81fa710ae26c0e591ebdc81154","status":"affected","versionType":"git"},{"version":"8ad342a863590b24ce77681b7e081363fb3333f7","lessThan":"44dab659064eb5c10adb0306510eebe848ed592d","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98344","source_modified_at":"2026-10-19T09:17:55.263Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"5.6","status":"affected"},{"version":"0","lessThan":"5.6","status":"unaffected","versionType":"semver"},{"version":"5.10.271","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.222","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.189","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.158","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.112","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.54","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.8","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}],"defaultStatus":"affected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98344","source_modified_at":"2026-10-19T09:17:55.263Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"036b527f92570206da4b8c40b38f8d689e29d0f3","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98344","source_modified_at":"2026-10-19T09:17:55.263Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"5fb1797a8c9485e40e5492fa0338ab5c7d1f3fef","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98344","source_modified_at":"2026-10-19T09:17:55.263Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"57f7f1c6827be7d8f80feca48d2125fb91c6f6ed","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98344","source_modified_at":"2026-10-19T09:17:55.263Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"7c3f4ce651d43705f9ec7f778f642a90d5ff4fba","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98344","source_modified_at":"2026-10-19T09:17:55.263Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"1a0d9b406febf23054ad595fd47b29325e70fb2d","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98344","source_modified_at":"2026-10-19T09:17:55.263Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"77906ac448d2fa81fa710ae26c0e591ebdc81154","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98344","source_modified_at":"2026-10-19T09:17:55.263Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"44dab659064eb5c10adb0306510eebe848ed592d","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":0.00184,"percentile":0.07616,"score_date":"2026-10-23"},"published_at":"2026-10-06T08:46:33.997Z","modified_at":"2026-10-19T09:17:55.263Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-98344","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-19T09:17:55.263Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-98344","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/036b527f92570206da4b8c40b38f8d689e29d0f3"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/5fb1797a8c9485e40e5492fa0338ab5c7d1f3fef"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/57f7f1c6827be7d8f80feca48d2125fb91c6f6ed"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/7c3f4ce651d43705f9ec7f778f642a90d5ff4fba"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/de2677e57d3161390d8a508f08cddec6ef7e4b23"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/1a0d9b406febf23054ad595fd47b29325e70fb2d"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/77906ac448d2fa81fa710ae26c0e591ebdc81154"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/44dab659064eb5c10adb0306510eebe848ed592d"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-19T09:17:55.263Z","content_hash":"6e9fe5463888c709a2d69eebe566dc7228a2303327299310c12cf44d926564f5"}}