spufs: fix gang directory lifetimes
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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
- 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: spufs: fix gang directory lifetimes prior to "[POWERPC] spufs: Fix gang destroy leaks" we used to have a problem with gang lifetimes - creation of a gang returns opened gang directory, which normally gets removed when that gets closed, but if somebody has created a context belonging to that gang and kept it alive until the gang got closed, removal failed and we ended up with a leak. Unfortunately, it had been fixed the wrong way. Dentry of gang directory was no longer pinned, and rmdir on close was gone. One problem was that failure of open kept calling simple_rmdir() as cleanup, which meant an unbalanced dput(). Another bug was in the success case - gang creation incremented link count on root directory, but that was no longer undone when gang got destroyed. Fix consists of • reverting the commit in question • adding a counter to gang, protected by ->i_rwsem of gang directory inode. • having it set to 1 at creation time, dropped in both spufs_dir_close() and spufs_gang_close() and bumped in spufs_create_context(), provided that it's not 0. • using simple_recursive_removal() to take the gang directory out when counter reaches zero.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
Version range not reported
- Linux Linux
2.6.22