{"id":"CVE-2026-98344","title":"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_cou…","summary":"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_cou…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 8ad342a863590b24ce77681b7e081363fb3333f7 < 036b527f92570206da4b8c40b38f8d689e29d0f3","Linux >= 8ad342a863590b24ce77681b7e081363fb3333f7 < 5fb1797a8c9485e40e5492fa0338ab5c7d1f3fef","Linux >= 8ad342a863590b24ce77681b7e081363fb3333f7 < 57f7f1c6827be7d8f80feca48d2125fb91c6f6ed","Linux >= 8ad342a863590b24ce77681b7e081363fb3333f7 < 7c3f4ce651d43705f9ec7f778f642a90d5ff4fba","Linux >= 8ad342a863590b24ce77681b7e081363fb3333f7 < de2677e57d3161390d8a508f08cddec6ef7e4b23","Linux >= 8ad342a863590b24ce77681b7e081363fb3333f7 < 1a0d9b406febf23054ad595fd47b29325e70fb2d","Linux >= 8ad342a863590b24ce77681b7e081363fb3333f7 < 77906ac448d2fa81fa710ae26c0e591ebdc81154","Linux >= 8ad342a863590b24ce77681b7e081363fb3333f7 < 44dab659064eb5c10adb0306510eebe848ed592d","Linux 5.6"],"published":"2026-10-06","updated":"2026-10-06","sourceUpdated":"2026-10-06T09:18:27.323","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-98344","references":[{"url":"https://git.kernel.org/stable/c/036b527f92570206da4b8c40b38f8d689e29d0f3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/1a0d9b406febf23054ad595fd47b29325e70fb2d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/44dab659064eb5c10adb0306510eebe848ed592d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/57f7f1c6827be7d8f80feca48d2125fb91c6f6ed","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5fb1797a8c9485e40e5492fa0338ab5c7d1f3fef","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/77906ac448d2fa81fa710ae26c0e591ebdc81154","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7c3f4ce651d43705f9ec7f778f642a90d5ff4fba","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/de2677e57d3161390d8a508f08cddec6ef7e4b23","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-10-06T08:50:17.400Z","slug":"CVE-2026-98344","body":"## Overview\n\nIn 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}