{"id":"CVE-2021-47119","details":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix memory leak in ext4_fill_super\n\nBuffer head references must be released before calling kill_bdev();\notherwise the buffer head (and its page referenced by b_data) will not\nbe freed by kill_bdev, and subsequently that bh will be leaked.\n\nIf blocksizes differ, sb_set_blocksize() will kill current buffers and\npage cache by using kill_bdev(). And then super block will be reread\nagain but using correct blocksize this time. sb_set_blocksize() didn't\nfully free superblock page and buffer head, and being busy, they were\nnot freed and instead leaked.\n\nThis can easily be reproduced by calling an infinite loop of:\n\n  systemctl start \u003cext4_on_lvm\u003e.mount, and\n  systemctl stop \u003cext4_on_lvm\u003e.mount\n\n... since systemd creates a cgroup for each slice which it mounts, and\nthe bh leak get amplified by a dying memory cgroup that also never\ngets freed, and memory consumption is much more easily noticed.","modified":"2026-03-13T05:20:34.457025Z","published":"2024-03-15T21:15:07.013Z","related":["SUSE-SU-2024:1454-1","SUSE-SU-2024:1465-1","SUSE-SU-2024:1489-1","SUSE-SU-2024:1643-1","SUSE-SU-2024:1646-1","SUSE-SU-2024:1870-1"],"references":[{"type":"FIX","url":"https://git.kernel.org/stable/c/01d349a481f0591230300a9171330136f9159bcd"},{"type":"FIX","url":"https://git.kernel.org/stable/c/1385b23396d511d5233b8b921ac3058b3f86a5e1"},{"type":"FIX","url":"https://git.kernel.org/stable/c/afd09b617db3786b6ef3dc43e28fe728cfea84df"}],"affected":[{"database_specific":{"unresolved_ranges":[{"events":[{"introduced":"2.6.19"},{"fixed":"5.10.43"}]},{"events":[{"introduced":"5.11"},{"fixed":"5.12.10"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc1"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc2"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc3"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc4"}]}],"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2021-47119.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}