{ "schema_version": "1.6.1", "id": "RPI-CVE-2026-72105", "modified": "2026-10-09T11:39:44Z", "upstream": [ "CVE-2026-72105" ], "published": "2026-08-15T06:04:33Z", "summary": "dm-log: fix a bitset_size overflow on 32bit machines", "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm-log: fix a bitset_size overflow on 32bit machines\n\nCommit c20e36b7631d (\"dm log: fix out-of-bounds write due to\nregion_count overflow\") made sure that region_count could fit in an\nunsigned int. But the bitmap memory isn't allocated based on\nregion_count. It uses bitset_size (a size_t variable). The first step of\ncalculating bitset_size is to set it to region_count, rounded up to a\nmultiple of BITS_PER_LONG. If region_size is less than BITS_PER_LONG\nsmaller than UINT_MAX, it will get rounded up to 2^32. On a 32bit\narchitecture, this will make bitset_size wrap around to 0 and fail,\ndespite region_count being valid.\n\nSince bitset_size gets divided by 8, it can hold any valid region_count.\nIt just needs a special case to handle the rollover. If it is 0, the\nvalue rolled over, and bitset size should be set to the number of bytes\nneeded to hold 2^32 bits.", "severity": [ { "type": "CVSS_V3", "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H" } ], "affected": [ { "package": { "ecosystem": "Raspberry Pi OS:12", "name": "linux" }, "versions": [ "1:6.12.93-1+rpt1", "1:6.12.96-1+rpt1" ], "ecosystem_specific": { "binaries": [ { "binary_name": "linux-image-6.12.93+rpt-rpi-2712", "binary_version": "1:6.12.93-1+rpt1" }, { "binary_name": "linux-image-6.12.93+rpt-rpi-v6", "binary_version": "1:6.12.93-1+rpt1" }, { "binary_name": "linux-image-6.12.93+rpt-rpi-v7", "binary_version": "1:6.12.93-1+rpt1" }, { "binary_name": "linux-image-6.12.93+rpt-rpi-v7l", "binary_version": "1:6.12.93-1+rpt1" }, { "binary_name": "linux-image-6.12.93+rpt-rpi-v8", "binary_version": "1:6.12.93-1+rpt1" }, { "binary_name": "linux-image-6.12.93+rpt-rpi-v8-rt", "binary_version": "1:6.12.93-1+rpt1" }, { "binary_name": "linux-image-6.12.96+rpt-rpi-2712", "binary_version": "1:6.12.96-1+rpt1" }, { "binary_name": "linux-image-6.12.96+rpt-rpi-v6", "binary_version": "1:6.12.96-1+rpt1" }, { "binary_name": "linux-image-6.12.96+rpt-rpi-v7", "binary_version": "1:6.12.96-1+rpt1" }, { "binary_name": "linux-image-6.12.96+rpt-rpi-v7l", "binary_version": "1:6.12.96-1+rpt1" }, { "binary_name": "linux-image-6.12.96+rpt-rpi-v8", "binary_version": "1:6.12.96-1+rpt1" }, { "binary_name": "linux-image-6.12.96+rpt-rpi-v8-rt", "binary_version": "1:6.12.96-1+rpt1" } ] }, "database_specific": { "per_version": { "1:6.12.93-1+rpt1": { "linux_commit": "d8ab4e908235da7727f22dd36ad5af224671677d", "upstream_version": "6.12.93", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.12.97" }, "1:6.12.96-1+rpt1": { "linux_commit": "ae161617d7a4552fa91d03626b8d9f3696d17481", "upstream_version": "6.12.96", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.12.97" } } } }, { "package": { "ecosystem": "Raspberry Pi OS:13", "name": "linux" }, "versions": [ "1:6.18.33-1+rpt1", "1:6.18.34-1+rpt1", "1:6.18.39-1+rpt1" ], "ecosystem_specific": { "binaries": [ { "binary_name": "linux-image-6.18.33+rpt-rpi-2712", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v6", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v7", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v8", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v8-rt", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-2712", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v6", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v7", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v8", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v8-rt", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-2712", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-v6", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-v7", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-v8", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-v8-rt", "binary_version": "1:6.18.39-1+rpt1" } ] }, "database_specific": { "per_version": { "1:6.18.33-1+rpt1": { "linux_commit": "95b85bebbedcaedfa7ca79116ed38b7376fba412", "upstream_version": "6.18.33", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.18.40" }, "1:6.18.34-1+rpt1": { "linux_commit": "c8c7494100e99ee05b11aaa4f0588a223a63d1af", "upstream_version": "6.18.34", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.18.40" }, "1:6.18.39-1+rpt1": { "linux_commit": "60ea684a8ace97bb0db1a16e20753bdd6ab371ff", "upstream_version": "6.18.39", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.18.40" } } } } ], "references": [ { "type": "ADVISORY", "url": "https://www.cve.org/CVERecord?id=CVE-2026-72105" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/cdc4ddf9db2cb79f4ab86b1a509b7ac21b0b6cf5" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/4b0de5a3ac1fd42acb0dc1f80ac5747e3287d723" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/567602fa72d57169365cbc589e0b8c3be900636d" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/d05e0edfecf5260e6dddd28b2f0cce02bfc6ed7a" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/1c3412b584e1fb6c665ff33ba7259253bc0082cb" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/e0b0163a65758ec3a2361ae1cea407898c27f21e" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/79feb87ab2396d49b9b65e4bb815d33cc71cba47" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/9743132a41f4d9d0e54c5f2adcb821b04796bab1" } ], "database_specific": { "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git", "upstream_modified": "2026-08-17T05:50:24Z", "severity": { "source": "kernel CNA", "cvss_v3_score": 7.8, "cvss_v3_severity": "High", "scenario": "AV:L - The flaw is reached only via local Device Mapper ioctls on /dev/mapper/control (dmsetup table load creating a mirror with core/disk log); there is no network, wireless, or physical-bus receive path into create_log_context().\nAC:L - A CAP_SYS_ADMIN attacker fully controls mirror table length and region_size via dmsetup, deterministically forcing region_count into the UINT_MAX-30..UINT_MAX wrap range on 32-bit kernels without races or victim-specific heap layout.\nPR:L - DM control ioctls require CAP_SYS_ADMIN, which is obtainable inside an unprivileged user namespace per kernel CNA guidance; mirror/dm-log setup is not limited to init-namespace root on typical container-capable systems.\nUI:N - Exploitation requires only the attacker issuing dmsetup/ioctl to create or resume a mirror with crafted parameters; no separate victim action such as mounting a filesystem or opening a file is needed.\nS:U - Impact is kernel vmalloc heap corruption and privilege escalation within the host kernel; it does not cross a VM, hypervisor, or IOMMU security boundary.\nC:H - Wrapping bitset_size to zero undersizes clean_bits/sync_bits/recovering_bits versus lc->region_count near UINT_MAX; subsequent log_test_bit/__set_bit_le calls during mirror I/O perform out-of-bounds reads of adjacent vmalloc heap memory.\nI:H - The same undersized bitmap sizing lets log_set_bit and log_clear_bit write far beyond the allocated bitset via region indices derived from dm mirror bios, corrupting adjacent kernel heap objects exploitable for arbitrary write or code execution.\nA:H - Identical dm-log bitset paths (e.g., core_in_sync calling log_test_bit) have been shown to kernel-crash with CR2 faults from out-of-bounds heap access; triggering this overflow causes oops, panic, or hang on affected 32-bit storage nodes." } } }