{"id":"DEBIAN-CVE-2024-50278","details":"In the Linux kernel, the following vulnerability has been resolved:  dm cache: fix potential out-of-bounds access on the first resume  Out-of-bounds access occurs if the fast device is expanded unexpectedly before the first-time resume of the cache table. This happens because expanding the fast device requires reloading the cache table for cache_create to allocate new in-core data structures that fit the new size, and the check in cache_preresume is not performed during the first resume, leading to the issue.  Reproduce steps:  1. prepare component devices:  dmsetup create cmeta --table \"0 8192 linear /dev/sdc 0\" dmsetup create cdata --table \"0 65536 linear /dev/sdc 8192\" dmsetup create corig --table \"0 524288 linear /dev/sdc 262144\" dd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1 oflag=direct  2. load a cache table of 512 cache blocks, and deliberately expand the    fast device before resuming the cache, making the in-core data    structures inadequate.  dmsetup create cache --notable dmsetup reload cache --table \"0 524288 cache /dev/mapper/cmeta \\ /dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0\" dmsetup reload cdata --table \"0 131072 linear /dev/sdc 8192\" dmsetup resume cdata dmsetup resume cache  3. suspend the cache to write out the in-core dirty bitset and hint    array, leading to out-of-bounds access to the dirty bitset at offset    0x40:  dmsetup suspend cache  KASAN reports:    BUG: KASAN: vmalloc-out-of-bounds in is_dirty_callback+0x2b/0x80   Read of size 8 at addr ffffc90000085040 by task dmsetup/90    (...snip...)   The buggy address belongs to the virtual mapping at    [ffffc90000085000, ffffc90000087000) created by:    cache_ctr+0x176a/0x35f0    (...snip...)   Memory state around the buggy address:    ffffc90000084f00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8    ffffc90000084f80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8   \u003effffc90000085000: 00 00 00 00 00 00 00 00 f8 f8 f8 f8 f8 f8 f8 f8                                              ^    ffffc90000085080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8    ffffc90000085100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8  Fix by checking the size change on the first resume.","modified":"2026-09-15T09:03:15.764835036Z","published":"2024-11-19T02:16:30.113Z","upstream":["CVE-2024-50278"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2024-50278"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.119-1"}]}],"versions":["6.1.106-1","6.1.106-2","6.1.106-3","6.1.112-1","6.1.115-1","6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1","6.1.85-1","6.1.90-1","6.1.90-1~bpo11+1","6.1.94-1","6.1.94-1~bpo11+1","6.1.98-1","6.1.99-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-50278.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.11.9-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-50278.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.11.9-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-50278.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H"}]}