{"id":"CVE-2026-93049","summary":"mtd: mtdswap: Avoid freeing registered blktrans device twice","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nmtd: mtdswap: Avoid freeing registered blktrans device twice\n\nIn mtdswap_add_mtd(), debugfs setup failure after successful blktrans\nregistration can free mbd_dev twice.\n\nadd_mtd_blktrans_dev() initializes the blktrans device reference and\npublishes the disk. Once that succeeds, del_mtd_blktrans_dev() tears the\ndisk down and drops the blktrans reference; when that reference reaches\nzero, blktrans_dev_release() frees the mtd_blktrans_dev.\n\nThe debugfs failure path called del_mtd_blktrans_dev(mbd_dev), then fell\nthrough the common cleanup label and called kfree(mbd_dev) again. Clear\nthe local pointer after deregistration so the common cleanup can still\nrelease the mtdswap state without freeing the blktrans object twice.\n\nThis issue was found by a static analysis checker and confirmed by\nmanual source review.","modified":"2026-09-19T03:47:26.777296704Z","published":"2026-09-17T16:10:39.679Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93049.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0ce48c6ddea1a8e675a2eb0221b62a9950788f3c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/37be7bc2c2d09c18e939da20224405864a0090b9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5c349c533e72af2313c3be0f80a24d7407fa4777"},{"type":"WEB","url":"https://git.kernel.org/stable/c/779aa4c66a96bf43d2d62982ea1a9096a9128d87"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a82d93fcfdfd26af17049c34319dfdd079cd1901"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d5086911d532b82ca070d944aa08ddde00baefe4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ecadb9137aeaa0615183f8d23eabea2b45c862f1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/eec130fc9ffbbd08a5d5432683122b79aca2a726"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93049.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93049"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8"},{"fixed":"ecadb9137aeaa0615183f8d23eabea2b45c862f1"},{"fixed":"eec130fc9ffbbd08a5d5432683122b79aca2a726"},{"fixed":"d5086911d532b82ca070d944aa08ddde00baefe4"},{"fixed":"0ce48c6ddea1a8e675a2eb0221b62a9950788f3c"},{"fixed":"a82d93fcfdfd26af17049c34319dfdd079cd1901"},{"fixed":"5c349c533e72af2313c3be0f80a24d7407fa4777"},{"fixed":"37be7bc2c2d09c18e939da20224405864a0090b9"},{"fixed":"779aa4c66a96bf43d2d62982ea1a9096a9128d87"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93049.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.14.0"},{"fixed":"5.10.270"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.221"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.188"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.157"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.110"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.52"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.6"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93049.json"}}],"schema_version":"1.9.0"}