{"id":"CVE-2026-98342","summary":"dmaengine: wait for RCU readers before releasing dma_device","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ndmaengine: wait for RCU readers before releasing dma_device\n\ndma_issue_pending_all() walks the dma_device_list with\nlist_for_each_entry_rcu() under rcu_read_lock(). dma_device_release()\nunlinks the device with list_del_rcu() and then calls\ndevice-\u003edevice_release() (which in many drivers, such as plx_dma.c,\ndirectly calls kfree()).\n\nBecause there is no grace period between unlinking the device and\nfreeing it, concurrent RCU readers in dma_issue_pending_all() can\naccess the device after it has been freed.\n\nThe lockless walk originally relied on clients holding a dmaengine\nreference to pin the provider module, and therefore the device, for as\nlong as they might traverse the list. Commit 8ad342a86359 (\"dmaengine:\nAdd reference counting to dma_device struct\") decoupled the dma_device\nlifetime from the module reference, so the device can now be released\nwhile a reader is still walking the list.\n\nAdd synchronize_rcu() before the device is freed, so RCU readers are\nguaranteed to have finished. Keep it unconditional: providers that do\nnot implement device_release() free the device themselves once\ndma_async_device_unregister() returns. This call will delay for a grace\nperiod with dma_list_mutex held, which is safe and only teardown path is\ndelayed.","modified":"2026-10-07T02:47:32.185435096Z","published":"2026-10-06T08:46:32.366Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98342.json","cna_assigner":"Linux"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/14578c78405d51fa92e4ada4502a45f537c0fcb8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4448a539a0c39141cccc67be6cacde0f35024313"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4aed7e47a10b94ea3c5171e8d1382081accd2e03"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8577a5ec4f7e00443015ef99f646def093121a1b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ac8ce9f89638d6d79875cca7d8ae42566a9bde15"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cbb3310a5167e868a5e763e32b9a23b4d50669ee"},{"type":"WEB","url":"https://git.kernel.org/stable/c/dc750422170a563c7a81f6e49d36bb02c62ae37f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fc1f4884f1d46fc7a8cee6e2997ecc9e8d1c7f77"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98342.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98342"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"2ba05622b8b143b0c95968ba59bddfbd6d2f2559"},{"fixed":"ac8ce9f89638d6d79875cca7d8ae42566a9bde15"},{"fixed":"14578c78405d51fa92e4ada4502a45f537c0fcb8"},{"fixed":"cbb3310a5167e868a5e763e32b9a23b4d50669ee"},{"fixed":"8577a5ec4f7e00443015ef99f646def093121a1b"},{"fixed":"4448a539a0c39141cccc67be6cacde0f35024313"},{"fixed":"fc1f4884f1d46fc7a8cee6e2997ecc9e8d1c7f77"},{"fixed":"4aed7e47a10b94ea3c5171e8d1382081accd2e03"},{"fixed":"dc750422170a563c7a81f6e49d36bb02c62ae37f"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98342.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.29"},{"fixed":"5.10.271"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.222"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.189"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.158"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.112"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.54"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.8"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98342.json"}}],"schema_version":"1.9.0"}