{"id":"CVE-2021-47483","state":"PUBLISHED","title":"regmap: Fix possible double-free in regcache_rbtree_exit()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nregmap: Fix possible double-free in regcache_rbtree_exit()\n\nIn regcache_rbtree_insert_to_block(), when 'present' realloc failed,\nthe 'blk' which is supposed to assign to 'rbnode->block' will be freed,\nso 'rbnode->block' points a freed memory, in the error handling path of\nregcache_rbtree_init(), 'rbnode->block' will be freed again in\nregcache_rbtree_exit(), KASAN will report double-free as follows:\n\nBUG: KASAN: double-free or invalid-free in kfree+0xce/0x390\nCall Trace:\n slab_free_freelist_hook+0x10d/0x240\n kfree+0xce/0x390\n regcache_rbtree_exit+0x15d/0x1a0\n regcache_rbtree_init+0x224/0x2c0\n regcache_init+0x88d/0x1310\n __regmap_init+0x3151/0x4a80\n __devm_regmap_init+0x7d/0x100\n madera_spi_probe+0x10f/0x333 [madera_spi]\n spi_probe+0x183/0x210\n really_probe+0x285/0xc30\n\nTo fix this, moving up the assignment of rbnode->block to immediately after\nthe reallocation has succeeded so that the data structure stays valid even\nif the second reallocation fails.","publishedAt":"2024-05-22T08:19:34.852Z","updatedAt":"2026-08-05T08:48:00.568Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"e72dce9afbdbfa70d9b44f5908a50ff6c4858999","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"fc081477b47dfc3a6cb50a96087fc29674013fc2","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"758ced2c3878ff789801e6fee808e185c5cf08d6","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"3dae1a4eced3ee733d7222e69b8a55caf2d61091","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"1cead23c1c0bc766dacb900a3b0269f651ad596f","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"36e911a16b377bde0ad91a8c679069d0d310b1a6","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"50cc1462a668dc62949a1127388bc3af785ce047","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"55e6d8037805b3400096d621091dfbf713f97e83","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/base/regmap/regcache-rbtree.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.12","versionType":"semver"},{"version":"4.4.291","status":"unaffected","lessThanOrEqual":"4.4.*","versionType":"semver"},{"version":"4.9.289","status":"unaffected","lessThanOrEqual":"4.9.*","versionType":"semver"},{"version":"4.14.254","status":"unaffected","lessThanOrEqual":"4.14.*","versionType":"semver"},{"version":"4.19.215","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.157","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.77","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.14.16","status":"unaffected","lessThanOrEqual":"5.14.*","versionType":"semver"},{"version":"5.15","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/base/regmap/regcache-rbtree.c"]}],"references":["https://git.kernel.org/stable/c/e72dce9afbdbfa70d9b44f5908a50ff6c4858999","https://git.kernel.org/stable/c/fc081477b47dfc3a6cb50a96087fc29674013fc2","https://git.kernel.org/stable/c/758ced2c3878ff789801e6fee808e185c5cf08d6","https://git.kernel.org/stable/c/3dae1a4eced3ee733d7222e69b8a55caf2d61091","https://git.kernel.org/stable/c/1cead23c1c0bc766dacb900a3b0269f651ad596f","https://git.kernel.org/stable/c/36e911a16b377bde0ad91a8c679069d0d310b1a6","https://git.kernel.org/stable/c/50cc1462a668dc62949a1127388bc3af785ce047","https://git.kernel.org/stable/c/55e6d8037805b3400096d621091dfbf713f97e83"],"weaknesses":[],"ingestedAt":"2026-10-29T19:49:19.404Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2021/47xxx/CVE-2021-47483.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2021-47483","state":"PUBLISHED","datePublished":"2024-05-22T08:19:34.852Z","dateUpdated":"2026-08-05T08:48:00.568Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-05-22T06:20:56.200Z"},"containers":{"cna":{"title":"regmap: Fix possible double-free in regcache_rbtree_exit()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nregmap: Fix possible double-free in regcache_rbtree_exit()\n\nIn regcache_rbtree_insert_to_block(), when 'present' realloc failed,\nthe 'blk' which is supposed to assign to 'rbnode->block' will be freed,\nso 'rbnode->block' points a freed memory, in the error handling path of\nregcache_rbtree_init(), 'rbnode->block' will be freed again in\nregcache_rbtree_exit(), KASAN will report double-free as follows:\n\nBUG: KASAN: double-free or invalid-free in kfree+0xce/0x390\nCall Trace:\n slab_free_freelist_hook+0x10d/0x240\n kfree+0xce/0x390\n regcache_rbtree_exit+0x15d/0x1a0\n regcache_rbtree_init+0x224/0x2c0\n regcache_init+0x88d/0x1310\n __regmap_init+0x3151/0x4a80\n __devm_regmap_init+0x7d/0x100\n madera_spi_probe+0x10f/0x333 [madera_spi]\n spi_probe+0x183/0x210\n really_probe+0x285/0xc30\n\nTo fix this, moving up the assignment of rbnode->block to immediately after\nthe reallocation has succeeded so that the data structure stays valid even\nif the second reallocation fails."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"e72dce9afbdbfa70d9b44f5908a50ff6c4858999","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"fc081477b47dfc3a6cb50a96087fc29674013fc2","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"758ced2c3878ff789801e6fee808e185c5cf08d6","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"3dae1a4eced3ee733d7222e69b8a55caf2d61091","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"1cead23c1c0bc766dacb900a3b0269f651ad596f","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"36e911a16b377bde0ad91a8c679069d0d310b1a6","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"50cc1462a668dc62949a1127388bc3af785ce047","versionType":"git"},{"version":"3f4ff561bc88b074d5e868dde4012d89cbb06c87","status":"affected","lessThan":"55e6d8037805b3400096d621091dfbf713f97e83","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/base/regmap/regcache-rbtree.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.12","versionType":"semver"},{"version":"4.4.291","status":"unaffected","lessThanOrEqual":"4.4.*","versionType":"semver"},{"version":"4.9.289","status":"unaffected","lessThanOrEqual":"4.9.*","versionType":"semver"},{"version":"4.14.254","status":"unaffected","lessThanOrEqual":"4.14.*","versionType":"semver"},{"version":"4.19.215","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.157","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.77","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.14.16","status":"unaffected","lessThanOrEqual":"5.14.*","versionType":"semver"},{"version":"5.15","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/base/regmap/regcache-rbtree.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/e72dce9afbdbfa70d9b44f5908a50ff6c4858999"},{"url":"https://git.kernel.org/stable/c/fc081477b47dfc3a6cb50a96087fc29674013fc2"},{"url":"https://git.kernel.org/stable/c/758ced2c3878ff789801e6fee808e185c5cf08d6"},{"url":"https://git.kernel.org/stable/c/3dae1a4eced3ee733d7222e69b8a55caf2d61091"},{"url":"https://git.kernel.org/stable/c/1cead23c1c0bc766dacb900a3b0269f651ad596f"},{"url":"https://git.kernel.org/stable/c/36e911a16b377bde0ad91a8c679069d0d310b1a6"},{"url":"https://git.kernel.org/stable/c/50cc1462a668dc62949a1127388bc3af785ce047"},{"url":"https://git.kernel.org/stable/c/55e6d8037805b3400096d621091dfbf713f97e83"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L 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