Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1000 CNY

100.0%
Get alerts for future matching vulnerabilitiesLog in to subscribe
I. Basic Information for CVE-2021-47114
Vulnerability Information

Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
ocfs2: fix data corruption by fallocate
Source: NVD (National Vulnerability Database)
Vulnerability Description
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/
Source: NVD (National Vulnerability Database)
CVSS Information
N/A
Source: NVD (National Vulnerability Database)
Vulnerability Type
N/A
Source: NVD (National Vulnerability Database)
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel 存在安全漏洞,该漏洞源于 ocfs2 模块的 fallocate 会造成数据损坏。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
VendorProductAffected VersionsCPESubscribe
LinuxLinux 385820a38d5e7c70b20af4d68767b1920b1e4133 ~ 624fa7baa3788dc9e57840ba5b94bc22b03cda57 -
LinuxLinux 2.6.23 -
II. Public POCs for CVE-2021-47114
#POC DescriptionSource LinkShenlong Link
AI-Generated POCPremium

No public POC found.

Login to generate AI POC
III. Intelligence Information for CVE-2021-47114
Please Login to view more intelligence information
IV. Related Vulnerabilities
V. Comments for CVE-2021-47114

No comments yet


Leave a comment