Bug 2492277 (CVE-2026-53059)
| Summary: | CVE-2026-53059 kernel: dm log: fix out-of-bounds write due to region_count overflow | ||
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| Product: | [Other] Security Response | Reporter: | OSIDB Bzimport <bzimport> |
| Component: | vulnerability | Assignee: | Product Security <prodsec-ir-bot> |
| Status: | NEW --- | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | unspecified | CC: | rhel-process-autobot, watson-tool-maintainers |
| Target Milestone: | --- | Keywords: | Security |
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | --- | |
| Doc Text: |
A flaw was found in the Linux kernel's device-mapper log (dm log) component. A local attacker could exploit an integer overflow vulnerability where a 64-bit value is truncated to 32 bits, leading to undersized memory allocations. This allows for out-of-bounds writes to kernel memory during log operations. Successful exploitation of this flaw can cause a kernel crash, resulting in a Denial of Service (DoS) for the affected system.
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Story Points: | --- |
| Clone Of: | Environment: | ||
| Last Closed: | Type: | --- | |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
Upstream advisory: https://lore.kernel.org/linux-cve-announce/2026062401-CVE-2026-53059-f32e@gregkh/T This issue has been addressed in the following products: Red Hat Enterprise Linux 8 Via RHSA-2026:45115 https://access.redhat.com/errata/RHSA-2026:45115 This issue has been addressed in the following products: Red Hat Enterprise Linux 8 Via RHSA-2026:45116 https://access.redhat.com/errata/RHSA-2026:45116 This issue has been addressed in the following products: Red Hat Enterprise Linux 10 Via RHSA-2026:45114 https://access.redhat.com/errata/RHSA-2026:45114 This issue has been addressed in the following products: Red Hat Enterprise Linux 9 Via RHSA-2026:45192 https://access.redhat.com/errata/RHSA-2026:45192 This issue has been addressed in the following products: Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On Via RHSA-2026:47248 https://access.redhat.com/errata/RHSA-2026:47248 This issue has been addressed in the following products: Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions Red Hat Enterprise Linux 8.8 Telecommunications Update Service Via RHSA-2026:52649 https://access.redhat.com/errata/RHSA-2026:52649 This issue has been addressed in the following products: Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On Via RHSA-2026:53989 https://access.redhat.com/errata/RHSA-2026:53989 This issue has been addressed in the following products: Red Hat Enterprise Linux 10.0 Extended Update Support Via RHSA-2026:55445 https://access.redhat.com/errata/RHSA-2026:55445 This issue has been addressed in the following products: Red Hat Enterprise Linux 9.6 Extended Update Support Via RHSA-2026:56574 https://access.redhat.com/errata/RHSA-2026:56574 This issue has been addressed in the following products: Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions Via RHSA-2026:59663 https://access.redhat.com/errata/RHSA-2026:59663 This issue has been addressed in the following products: Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions Via RHSA-2026:59662 https://access.redhat.com/errata/RHSA-2026:59662 This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Extended Lifecycle Support Via RHSA-2026:61692 https://access.redhat.com/errata/RHSA-2026:61692 This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Extended Lifecycle Support Via RHSA-2026:63189 https://access.redhat.com/errata/RHSA-2026:63189 |
In the Linux kernel, the following vulnerability has been resolved: dm log: fix out-of-bounds write due to region_count overflow The local variable region_count in create_log_context() is declared as unsigned int (32-bit), but dm_sector_div_up() returns sector_t (64-bit). When a device-mapper target has a sufficiently large ti->len with a small region_size, the division result can exceed UINT_MAX. The truncated value is then used to calculate bitset_size, causing clean_bits, sync_bits, and recovering_bits to be allocated far smaller than needed for the actual number of regions. Subsequent log operations (log_set_bit, log_clear_bit, log_test_bit) use region indices derived from the full untruncated region space, causing out-of-bounds writes to kernel heap memory allocated by vmalloc. This can be reproduced by creating a mirror target whose region_count overflows 32 bits: dmsetup create bigzero --table '0 8589934594 zero' dmsetup create mymirror --table '0 8589934594 mirror \ core 2 2 nosync 2 /dev/mapper/bigzero 0 \ /dev/mapper/bigzero 0' The status output confirms the truncation (sync_count=1 instead of 4294967297, because 0x100000001 was truncated to 1): $ dmsetup status mymirror 0 8589934594 mirror 2 254:1 254:1 1/4294967297 ... This leads to a kernel crash in core_in_sync: BUG: scheduling while atomic: (udev-worker)/9150/0x00000000 RIP: 0010:core_in_sync+0x14/0x30 [dm_log] CR2: 0000000000000008 Fixing recursive fault but reboot is needed! Fix by widening the local region_count to sector_t and adding an explicit overflow check before the value is assigned to lc->region_count.