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/20210525093034.GB4112@quack2.suse.cz/T/
Metrics
Affected Vendors & Products
References
History
Fri, 04 Apr 2025 15:00:00 +0000
Type | Values Removed | Values Added |
---|---|---|
First Time appeared |
Linux
Linux linux Kernel |
|
Weaknesses | NVD-CWE-noinfo | |
CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:* |
|
Vendors & Products |
Linux
Linux linux Kernel |
Mon, 04 Nov 2024 13:15:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Metrics |
ssvc
|

Status: PUBLISHED
Assigner: Linux
Published: 2024-03-15T20:14:22.035Z
Updated: 2025-05-04T07:04:26.904Z
Reserved: 2024-03-04T18:12:48.836Z
Link: CVE-2021-47114

Updated: 2024-08-04T05:24:39.898Z

Status : Analyzed
Published: 2024-03-15T21:15:06.723
Modified: 2025-04-04T14:39:41.120
Link: CVE-2021-47114
