nfsd: fix possible fh_compose of wrong dentry in nfsd4_create_file()
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 7.2.4
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: nfsd: fix possible fh_compose of wrong dentry in nfsd4_create_file() dentry_create() can hypothetically provide a different dentry than the one passed in. This could happen, for example, if the exported filesystem is NFS, and the server returned to OPEN a filehandle which matched a directory that was already in the dcache. Clearly this would not be expected! If this were to happen the dentry (child) that was already stored in resfhp could be freed and later dereferenced. We shouldn't call fh_compose() until we are certain that we have the final dentry, so this patch moved the fh_compose() call to two places: one for the case where the target already exists, and one after dentry_create() where it was created.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 64a989dbd144e0622371396461b11335459692d2 · fixed in 033e783709ce99662cf81f6abcad746a8da9d35f; From 64a989dbd144e0622371396461b11335459692d2 · fixed in 3e2c79360c6a89975ec5b5a7d4ef937e4db91a27
- Linux Linux
7.0
- KernelLinux
From 7.0.0 · fixed in 7.2.4