CVSS 7.8 · High EPSS 0,14%
Kerentanan Out-of-bounds Write pada linux kernel. Skor CVSS 3.1 7.8 (High) menurut NVD.
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.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
· uraikan di kalkulator | Vendor | Produk | Versi terdampak |
|---|---|---|
| linux | linux kernel | Versi 2.6.12.1 hingga sebelum 5.10.258 |
| linux | linux kernel | Versi 5.11 hingga sebelum 5.15.209 |
| linux | linux kernel | Versi 5.16 hingga sebelum 6.1.175 |
| linux | linux kernel | Versi 6.2 hingga sebelum 6.6.141 |
| linux | linux kernel | Versi 6.7 hingga sebelum 6.12.91 |
| linux | linux kernel | Versi 6.13 hingga sebelum 6.18.33 |
| linux | linux kernel | Versi 6.19 hingga sebelum 7.0.10 |
| linux | linux kernel | Versi 2.6.12 |
| linux | linux kernel | Versi 2.6.12 rc2 |
| linux | linux kernel | Versi 2.6.12 rc3 |
| linux | linux kernel | Versi 2.6.12 rc4 |
| linux | linux kernel | Versi 2.6.12 rc5 |