https://cve.radiocsirt.org Contains only the most 10 recent entries. http://www.rssboard.org/rss-specification python-feedgen en Wed, 07 Oct 2026 16:35:25 +0000 https://cve.radiocsirt.org/vuln/cve-2021-47119 <p><strong>Affected:</strong> Linux</p> <p>In the Linux kernel, the following vulnerability has been resolved:</p> <p>ext4: fix memory leak in ext4_fill_super</p> <p>Buffer head references must be released before calling kill_bdev(); otherwise the buffer head (and its page referenced by b_data) will not be freed by kill_bdev, and subsequently that bh will be leaked.</p> <p>If blocksizes differ, sb_set_blocksize() will kill current buffers and page cache by using kill_bdev(). And then super block will be reread again but using correct blocksize this time. sb_set_blocksize() didn&#39;t fully free superblock page and buffer head, and being busy, they were not freed and instead leaked.</p> <p>This can easily be reproduced by calling an infinite loop of:</p> <p>systemctl start &lt;ext4_on_lvm&gt;.mount, and systemctl stop &lt;ext4_on_lvm&gt;.mount</p> <p>... since systemd creates a cgroup for each slice which it mounts, and the bh leak get amplified by a dying memory cgroup that also never gets freed, and memory consumption is much more easily noticed.</p> <p><strong>Affected:</strong> Linux</p> <p>In the Linux kernel, the following vulnerability has been resolved:</p> <p>ext4: fix memory leak in ext4_fill_super</p> <p>Buffer head references must be released before calling kill_bdev(); otherwise the buffer head (and its page referenced by b_data) will not be freed by kill_bdev, and subsequently that bh will be leaked.</p> <p>If blocksizes differ, sb_set_blocksize() will kill current buffers and page cache by using kill_bdev(). And then super block will be reread again but using correct blocksize this time. sb_set_blocksize() didn&#39;t fully free superblock page and buffer head, and being busy, they were not freed and instead leaked.</p> <p>This can easily be reproduced by calling an infinite loop of:</p> <p>systemctl start &lt;ext4_on_lvm&gt;.mount, and systemctl stop &lt;ext4_on_lvm&gt;.mount</p> <p>... since systemd creates a cgroup for each slice which it mounts, and the bh leak get amplified by a dying memory cgroup that also never gets freed, and memory consumption is much more easily noticed.</p> https://cve.radiocsirt.org/vuln/cve-2021-47119