CVE-2021-47114
- Source
- https://nvd.nist.gov/vuln/detail/CVE-2021-47114
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-47114.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2021-47114
- Related
- Published
- 2024-03-15T21:15:06Z
- Modified
- 2024-11-05T17:35:00Z
- Summary
- [none]
- Details
-
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 ocfs2writepage()->blockwritefullpage() 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.convThe 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) = 0v1: https://www.spinics.net/lists/linux-fsdevel/msg193999.html v2: https://lore.kernel.org/linux-fsdevel/20210525093034.GB4112@quack2.suse.cz/T/
- References
-
- https://git.kernel.org/stable/c/0a31dd6fd2f4e7db538fb6eb1f06973d81f8dd3b
- https://git.kernel.org/stable/c/33e03adafb29eedae1bae9cdb50c1385279fcf65
- https://git.kernel.org/stable/c/624fa7baa3788dc9e57840ba5b94bc22b03cda57
- https://git.kernel.org/stable/c/6bba4471f0cc1296fe3c2089b9e52442d3074b2e
- https://git.kernel.org/stable/c/a1700479524bb9cb5e8ae720236a6fabd003acae
- https://git.kernel.org/stable/c/c8d5faee46242c3f33b8a71a4d7d52214785bfcc
- https://git.kernel.org/stable/c/cc2edb99ea606a45182b5ea38cc8f4e583aa0774
- https://git.kernel.org/stable/c/cec4e857ffaa8c447f51cd8ab4e72350077b6770
- https://security-tracker.debian.org/tracker/CVE-2021-47114
Affected packages
Debian:11 / linux
Package
- Name
- linux
- Purl
- pkg:deb/debian/linux?arch=source
Debian:12 / linux
Package
- Name
- linux
- Purl
- pkg:deb/debian/linux?arch=source
Debian:13 / linux
Package
- Name
- linux
- Purl
- pkg:deb/debian/linux?arch=source