{"id":"CVE-2026-93049","state":"PUBLISHED","title":"mtd: mtdswap: Avoid freeing registered blktrans device twice","description":"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.","publishedAt":"2026-09-17T16:10:39.679Z","updatedAt":"2026-10-19T09:04:44.322Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"ecadb9137aeaa0615183f8d23eabea2b45c862f1","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"eec130fc9ffbbd08a5d5432683122b79aca2a726","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"d5086911d532b82ca070d944aa08ddde00baefe4","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"0ce48c6ddea1a8e675a2eb0221b62a9950788f3c","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"a82d93fcfdfd26af17049c34319dfdd079cd1901","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"5c349c533e72af2313c3be0f80a24d7407fa4777","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"37be7bc2c2d09c18e939da20224405864a0090b9","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"779aa4c66a96bf43d2d62982ea1a9096a9128d87","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/mtd/mtdswap.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.14","versionType":"semver"},{"version":"5.10.270","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/mtd/mtdswap.c"]}],"references":["https://git.kernel.org/stable/c/ecadb9137aeaa0615183f8d23eabea2b45c862f1","https://git.kernel.org/stable/c/eec130fc9ffbbd08a5d5432683122b79aca2a726","https://git.kernel.org/stable/c/d5086911d532b82ca070d944aa08ddde00baefe4","https://git.kernel.org/stable/c/0ce48c6ddea1a8e675a2eb0221b62a9950788f3c","https://git.kernel.org/stable/c/a82d93fcfdfd26af17049c34319dfdd079cd1901","https://git.kernel.org/stable/c/5c349c533e72af2313c3be0f80a24d7407fa4777","https://git.kernel.org/stable/c/37be7bc2c2d09c18e939da20224405864a0090b9","https://git.kernel.org/stable/c/779aa4c66a96bf43d2d62982ea1a9096a9128d87"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:34.582Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/93xxx/CVE-2026-93049.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-93049","state":"PUBLISHED","datePublished":"2026-09-17T16:10:39.679Z","dateUpdated":"2026-10-19T09:04:44.322Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-17T15:57:05.658Z"},"containers":{"cna":{"title":"mtd: mtdswap: Avoid freeing registered blktrans device twice","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"ecadb9137aeaa0615183f8d23eabea2b45c862f1","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"eec130fc9ffbbd08a5d5432683122b79aca2a726","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"d5086911d532b82ca070d944aa08ddde00baefe4","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"0ce48c6ddea1a8e675a2eb0221b62a9950788f3c","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"a82d93fcfdfd26af17049c34319dfdd079cd1901","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"5c349c533e72af2313c3be0f80a24d7407fa4777","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"37be7bc2c2d09c18e939da20224405864a0090b9","versionType":"git"},{"version":"e8e3edb95ce6a146bc774b6cfad3553f4383edc8","status":"affected","lessThan":"779aa4c66a96bf43d2d62982ea1a9096a9128d87","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/mtd/mtdswap.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.14","versionType":"semver"},{"version":"5.10.270","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/mtd/mtdswap.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/ecadb9137aeaa0615183f8d23eabea2b45c862f1"},{"url":"https://git.kernel.org/stable/c/eec130fc9ffbbd08a5d5432683122b79aca2a726"},{"url":"https://git.kernel.org/stable/c/d5086911d532b82ca070d944aa08ddde00baefe4"},{"url":"https://git.kernel.org/stable/c/0ce48c6ddea1a8e675a2eb0221b62a9950788f3c"},{"url":"https://git.kernel.org/stable/c/a82d93fcfdfd26af17049c34319dfdd079cd1901"},{"url":"https://git.kernel.org/stable/c/5c349c533e72af2313c3be0f80a24d7407fa4777"},{"url":"https://git.kernel.org/stable/c/37be7bc2c2d09c18e939da20224405864a0090b9"},{"url":"https://git.kernel.org/stable/c/779aa4c66a96bf43d2d62982ea1a9096a9128d87"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:04:44.322Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"5.10.270"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"6.18.52"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}