cbcvebase.
CVE-2021-47119
published 2024-03-15

CVE-2021-47119: In the Linux kernel, the following vulnerability has been resolved: ext4: fix memory leak in ext4_fill_super Buffer head references must be released before…

PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.25%
16.6th percentile
In the Linux kernel, the following vulnerability has been resolved: ext4: fix memory leak in ext4_fill_super 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. 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't fully free superblock page and buffer head, and being busy, they were not freed and instead leaked. This can easily be reproduced by calling an infinite loop of: systemctl start .mount, and systemctl stop .mount ... 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.

Affected

16 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.10.46-1 (bookworm)linux 5.10.46-1 (bookworm)
linuxlinux
linuxlinux>= ac27a0ec112a089f1a5102bc8dffc79c8c815571 < 01d349a481f0591230300a9171330136f9159bcd01d349a481f0591230300a9171330136f9159bcd
linuxlinux>= ac27a0ec112a089f1a5102bc8dffc79c8c815571 < 1385b23396d511d5233b8b921ac3058b3f86a5e11385b23396d511d5233b8b921ac3058b3f86a5e1
linuxlinux>= ac27a0ec112a089f1a5102bc8dffc79c8c815571 < afd09b617db3786b6ef3dc43e28fe728cfea84dfafd09b617db3786b6ef3dc43e28fe728cfea84df
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.4.0-214.2345.4.0-214.234
linuxlinux_kernel>= 0 < 3.13.0-205.2563.13.0-205.256
linuxlinux_kernel>= 0 < 4.4.0-267.3014.4.0-267.301
linuxlinux_kernel>= 0 < 4.15.0-236.2484.15.0-236.248
linuxlinux_kernel>= 2.6.19 < 5.10.435.10.43
linuxlinux_kernel>= 5.11 < 5.12.105.12.10

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv7.1HIGH
vendor_ubuntu7.1HIGH
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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