{"id":"DEBIAN-CVE-2021-47343","details":"In the Linux kernel, the following vulnerability has been resolved:  dm btree remove: assign new_root only when removal succeeds  remove_raw() in dm_btree_remove() may fail due to IO read error (e.g. read the content of origin block fails during shadowing), and the value of shadow_spine::root is uninitialized, but the uninitialized value is still assign to new_root in the end of dm_btree_remove().  For dm-thin, the value of pmd-\u003edetails_root or pmd-\u003eroot will become an uninitialized value, so if trying to read details_info tree again out-of-bound memory may occur as showed below:    general protection fault, probably for non-canonical address 0x3fdcb14c8d7520   CPU: 4 PID: 515 Comm: dmsetup Not tainted 5.13.0-rc6   Hardware name: QEMU Standard PC   RIP: 0010:metadata_ll_load_ie+0x14/0x30   Call Trace:    sm_metadata_count_is_more_than_one+0xb9/0xe0    dm_tm_shadow_block+0x52/0x1c0    shadow_step+0x59/0xf0    remove_raw+0xb2/0x170    dm_btree_remove+0xf4/0x1c0    dm_pool_delete_thin_device+0xc3/0x140    pool_message+0x218/0x2b0    target_message+0x251/0x290    ctl_ioctl+0x1c4/0x4d0    dm_ctl_ioctl+0xe/0x20    __x64_sys_ioctl+0x7b/0xb0    do_syscall_64+0x40/0xb0    entry_SYSCALL_64_after_hwframe+0x44/0xae  Fixing it by only assign new_root when removal succeeds","modified":"2026-09-01T20:04:37.542371489Z","published":"2024-05-21T15:15:20.993Z","upstream":["CVE-2021-47343"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2021-47343"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.14.6-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47343.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.14.6-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47343.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.14.6-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47343.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:N/I:N/A:H"}]}