{"id":"CVE-2026-53059","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-53059","summary":"dm log: fix out-of-bounds write due to region_count overflow","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ndm log: fix out-of-bounds write due to region_count overflow\n\nThe local variable region_count in create_log_context() is declared as\nunsigned int (32-bit), but dm_sector_div_up() returns sector_t (64-bit).\nWhen a device-mapper target has a sufficiently large ti->len with a small\nregion_size, the division result can exceed UINT_MAX. The truncated\nvalue is then used to calculate bitset_size, causing clean_bits,\nsync_bits, and recovering_bits to be allocated far smaller than needed\nfor the actual number of regions.\n\nSubsequent log operations (log_set_bit, log_clear_bit, log_test_bit) use\nregion indices derived from the full untruncated region space, causing\nout-of-bounds writes to kernel heap memory allocated by vmalloc.\n\nThis can be reproduced by creating a mirror target whose region_count\noverflows 32 bits:\n\n  dmsetup create bigzero --table '0 8589934594 zero'\n  dmsetup create mymirror --table '0 8589934594 mirror \\\n    core 2 2 nosync 2 /dev/mapper/bigzero 0 \\\n    /dev/mapper/bigzero 0'\n\nThe status output confirms the truncation (sync_count=1 instead of\n4294967297, because 0x100000001 was truncated to 1):\n\n  $ dmsetup status mymirror\n  0 8589934594 mirror 2 254:1 254:1 1/4294967297 ...\n\nThis leads to a kernel crash in core_in_sync:\n\n  BUG: scheduling while atomic: (udev-worker)/9150/0x00000000\n  RIP: 0010:core_in_sync+0x14/0x30 [dm_log]\n  CR2: 0000000000000008\n  Fixing recursive fault but reboot is needed!\n\nFix by widening the local region_count to sector_t and adding an\nexplicit overflow check before the value is assigned to lc->region_count.","published":"2026-06-24T16:30:04.210Z","modified":"2026-09-29T09:26:39.069320955Z","cvss":{"score":6.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"5.10.258"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/12bd5b88e91a02785244ff1d20fb157e96e9cdc8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3ec74da927b4e171a6fc0e77b1188ba4d019af51"},{"type":"WEB","url":"https://git.kernel.org/stable/c/44ab8875ae4a2842bde2d756bed195d375e0debb"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4ec8323b9f0764a14d532b1ae9b87f8a9fecb867"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b455903eed4558982be0811f5b7f44f6bbc4ff57"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c20e36b7631d83e7535877f08af8b0af72c44b1a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d4ac87567f86a55c3c92e9a5144dcd943a9772a1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/defe483e47173768c227532694dc78cb65db5f09"},{"type":"WEB","url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53059.json"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:45114"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:45115"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:45116"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:45192"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:47248"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:52649"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:53989"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:55445"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:56574"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:59662"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:59663"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:61692"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:63189"},{"type":"ADVISORY","url":"https://access.redhat.com/security/cve/CVE-2026-53059"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53059.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53059"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2492277"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-29T09:26:39.069320955Z"}}