CVSS 5.5 · Medium EPSS 0,13%
Kerentanan Missing Release of Memory after Effective Lifetime pada linux kernel. Skor CVSS 3.1 5.5 (Medium) menurut NVD.
In the Linux kernel, the following vulnerability has been resolved: dm cache metadata: fix memory leak on metadata abort retry When failing to acquire the root_lock in dm_cache_metadata_abort because the block_manager is read-only, the temporary block_manager created outside the root_lock is not properly released, causing a memory leak. Reproduce steps: This can be reproduced by reloading a new table while the metadata is read-only. While the second call to dm_cache_metadata_abort is caused by lack of support for table preload in dm-cache, mentioned in commit 9b1cc9f251af ("dm cache: share cache-metadata object across inactive and active DM tables"), it exposes the memory leak in dm_cache_metadata_abort when the function is called multiple times. Specifically, dm-cache fails to sync the new cache object's mode during preresume, creating the reproducer condition. This issue could also occur through concurrent metadata_operation_failed calls due to races in cache mode updates, but the table preload scenario below provides a reliable reproducer. 1. Create a cache device with some faulty trailing metadata blocks dmsetup create cmeta <<EOF 0 200 linear /dev/sdc 0 200 7992 error EOF dmsetup create cdata --table "0 131072 linear /dev/sdc 8192" dmsetup create corig --table "0 262144 linear /dev/sdc 262144" dd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1 oflag=direct dmsetup create cache --table "0 131072 cache /dev/mapper/cmeta \ /dev/mapper/cdata /dev/mapper/corig 128 1 writethrough smq 0" 2. Suspend and resume the cache to start a new metadata transaction and trigger metadata io errors on the next metadata commit. dmsetup suspend cache dmsetup resume cache 3. Write to the cache device to update metadata fio --filename=/dev/mapper/cache --name test --rw=randwrite --bs=4k \ --randrepeat=0 --direct=1 --size 64k 4. Preload the same table dmsetup reload cache --table "$(dmsetup table cache)" 5. Resume the new table. This triggers the memory leak. dmsetup suspend cache dmsetup resume cache kmemleak logs: <snip> unreferenced object 0xffff8880080c2010 (size 16): comm "dmsetup", pid 132, jiffies 4294982580 hex dump (first 16 bytes): 00 38 b9 07 80 88 ff ff 6a 6b 6b 6b 6b 6b 6b a5 ... backtrace (crc 3118f31c): kmemleak_alloc+0x28/0x40 __kmalloc_cache_noprof+0x3d9/0x510 dm_block_manager_create+0x51/0x140 dm_cache_metadata_abort+0x85/0x320 metadata_operation_failed+0x103/0x1e0 cache_preresume+0xacd/0xe70 dm_table_resume_targets+0xd3/0x320 __dm_resume+0x1b/0xf0 dm_resume+0x127/0x170 <snip>
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
· uraikan di kalkulator | Vendor | Produk | Versi terdampak |
|---|---|---|
| linux | linux kernel | Versi 4.9.337 hingga sebelum 4.10 |
| linux | linux kernel | Versi 4.14.303 hingga sebelum 4.15 |
| linux | linux kernel | Versi 4.19.270 hingga sebelum 4.20 |
| linux | linux kernel | Versi 5.4.229 hingga sebelum 5.5 |
| linux | linux kernel | Versi 5.10.163 hingga sebelum 5.10.258 |
| linux | linux kernel | Versi 5.15.87 hingga sebelum 5.15.209 |
| linux | linux kernel | Versi 6.0.18 hingga sebelum 6.1 |
| linux | linux kernel | Versi 6.1.4 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 |