| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2021-47483: regmap: Fix possible double-free in regcache_rbtree_exit() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| regmap: Fix possible double-free in regcache_rbtree_exit() |
| |
| In regcache_rbtree_insert_to_block(), when 'present' realloc failed, |
| the 'blk' which is supposed to assign to 'rbnode->block' will be freed, |
| so 'rbnode->block' points a freed memory, in the error handling path of |
| regcache_rbtree_init(), 'rbnode->block' will be freed again in |
| regcache_rbtree_exit(), KASAN will report double-free as follows: |
| |
| BUG: KASAN: double-free or invalid-free in kfree+0xce/0x390 |
| Call Trace: |
| slab_free_freelist_hook+0x10d/0x240 |
| kfree+0xce/0x390 |
| regcache_rbtree_exit+0x15d/0x1a0 |
| regcache_rbtree_init+0x224/0x2c0 |
| regcache_init+0x88d/0x1310 |
| __regmap_init+0x3151/0x4a80 |
| __devm_regmap_init+0x7d/0x100 |
| madera_spi_probe+0x10f/0x333 [madera_spi] |
| spi_probe+0x183/0x210 |
| really_probe+0x285/0xc30 |
| |
| To fix this, moving up the assignment of rbnode->block to immediately after |
| the reallocation has succeeded so that the data structure stays valid even |
| if the second reallocation fails. |
| |
| The Linux kernel CVE team has assigned CVE-2021-47483 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 3.12 with commit 3f4ff561bc88b074d5e868dde4012d89cbb06c87 and fixed in 4.4.291 with commit e72dce9afbdbfa70d9b44f5908a50ff6c4858999 |
| Issue introduced in 3.12 with commit 3f4ff561bc88b074d5e868dde4012d89cbb06c87 and fixed in 4.9.289 with commit fc081477b47dfc3a6cb50a96087fc29674013fc2 |
| Issue introduced in 3.12 with commit 3f4ff561bc88b074d5e868dde4012d89cbb06c87 and fixed in 4.14.254 with commit 758ced2c3878ff789801e6fee808e185c5cf08d6 |
| Issue introduced in 3.12 with commit 3f4ff561bc88b074d5e868dde4012d89cbb06c87 and fixed in 4.19.215 with commit 3dae1a4eced3ee733d7222e69b8a55caf2d61091 |
| Issue introduced in 3.12 with commit 3f4ff561bc88b074d5e868dde4012d89cbb06c87 and fixed in 5.4.157 with commit 1cead23c1c0bc766dacb900a3b0269f651ad596f |
| Issue introduced in 3.12 with commit 3f4ff561bc88b074d5e868dde4012d89cbb06c87 and fixed in 5.10.77 with commit 36e911a16b377bde0ad91a8c679069d0d310b1a6 |
| Issue introduced in 3.12 with commit 3f4ff561bc88b074d5e868dde4012d89cbb06c87 and fixed in 5.14.16 with commit 50cc1462a668dc62949a1127388bc3af785ce047 |
| Issue introduced in 3.12 with commit 3f4ff561bc88b074d5e868dde4012d89cbb06c87 and fixed in 5.15 with commit 55e6d8037805b3400096d621091dfbf713f97e83 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2021-47483 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| drivers/base/regmap/regcache-rbtree.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| 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 |
