cbcvebase.
CVE-2021-47114
published 2024-03-15

CVE-2021-47114: In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix data corruption by fallocate When fallocate punches holes out of inode size, if…

PriorityP421medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.23%
13.4th percentile
In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix data corruption by fallocate When fallocate punches holes out of inode size, if original isize is in the middle of last cluster, then the part from isize to the end of the cluster will be zeroed with buffer write, at that time isize is not yet updated to match the new size, if writeback is kicked in, it will invoke ocfs2_writepage()->block_write_full_page() where the pages out of inode size will be dropped. That will cause file corruption. Fix this by zero out eof blocks when extending the inode size. Running the following command with qemu-image 4.2.1 can get a corrupted coverted image file easily. qemu-img convert -p -t none -T none -f qcow2 $qcow_image \ -O qcow2 -o compat=1.1 $qcow_image.conv The usage of fallocate in qemu is like this, it first punches holes out of inode size, then extend the inode size. fallocate(11, FALLOC_FL_KEEP_SIZE|FALLOC_FL_PUNCH_HOLE, 2276196352, 65536) = 0 fallocate(11, 0, 2276196352, 65536) = 0 v1: https://www.spinics.net/lists/linux-fsdevel/msg193999.html v2: https://lore.kernel.org/linux-fsdevel/[email protected]/T/

Affected

22 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.10.46-1 (bookworm)linux 5.10.46-1 (bookworm)
linuxlinux——
linuxlinux>= 385820a38d5e7c70b20af4d68767b1920b1e4133 < 624fa7baa3788dc9e57840ba5b94bc22b03cda57624fa7baa3788dc9e57840ba5b94bc22b03cda57
linuxlinux>= 385820a38d5e7c70b20af4d68767b1920b1e4133 < 33e03adafb29eedae1bae9cdb50c1385279fcf6533e03adafb29eedae1bae9cdb50c1385279fcf65
linuxlinux>= 385820a38d5e7c70b20af4d68767b1920b1e4133 < a1700479524bb9cb5e8ae720236a6fabd003acaea1700479524bb9cb5e8ae720236a6fabd003acae
linuxlinux>= 385820a38d5e7c70b20af4d68767b1920b1e4133 < cec4e857ffaa8c447f51cd8ab4e72350077b6770cec4e857ffaa8c447f51cd8ab4e72350077b6770
linuxlinux>= 385820a38d5e7c70b20af4d68767b1920b1e4133 < cc2edb99ea606a45182b5ea38cc8f4e583aa0774cc2edb99ea606a45182b5ea38cc8f4e583aa0774
linuxlinux>= 385820a38d5e7c70b20af4d68767b1920b1e4133 < c8d5faee46242c3f33b8a71a4d7d52214785bfccc8d5faee46242c3f33b8a71a4d7d52214785bfcc
linuxlinux>= 385820a38d5e7c70b20af4d68767b1920b1e4133 < 0a31dd6fd2f4e7db538fb6eb1f06973d81f8dd3b0a31dd6fd2f4e7db538fb6eb1f06973d81f8dd3b
linuxlinux>= 385820a38d5e7c70b20af4d68767b1920b1e4133 < 6bba4471f0cc1296fe3c2089b9e52442d3074b2e6bba4471f0cc1296fe3c2089b9e52442d3074b2e
linuxlinux_kernel< 4.4.2724.4.272
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>= 4.10 < 4.14.2364.14.236
linuxlinux_kernel>= 4.15 < 4.19.1944.19.194
linuxlinux_kernel>= 4.20 < 5.4.1255.4.125
linuxlinux_kernel>= 4.5 < 4.9.2724.9.272
linuxlinux_kernel>= 5.11 < 5.12.105.12.10
linuxlinux_kernel>= 5.5 < 5.10.435.10.43

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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