Re: [PATCH v2] audit: Avoid excessive dput/dget in audit_context setup and reset paths
Al Viro <[email protected]>
| Newsgroups | org.kernel.vger.audit,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <20260205235351.GU3183987@ZenIV> |
On Wed, Feb 04, 2026 at 11:45:17PM -0500, Waiman Long wrote: > @@ -70,6 +74,8 @@ void chroot_fs_refs(const struct path *old_root, const > struct> > Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â count++; > Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â path_get(new_root); > Â Â Â Â Â Â Â Â Â Â Â Â } > +Â Â Â Â Â Â Â Â Â Â Â Â count += fs->pwd_xrefs; > +Â Â Â Â Â Â Â Â Â Â Â Â fs->pwd_xrefs = 0; > Â Â Â Â Â Â Â Â Â Â Â Â write_sequnlock(&fs->seq); Nope - you only need that for threads that have ->pwd equal to old_root. Incidentally, I'd forgotten about that sucker - it kills the idea of fdget-like tricks dead, more's the pity. Third-party modification of task->fs->pwd (under task->lock and task->fs->seq), possible even with task->fs->users == 1. FWIW, I'm going through the fs_struct uses at the moment; will post whatever I get when I go down (or earlier, in the unlikely case it doesn't spill to tomorrow morning), will keep posting incremental followups until the documentation is done. I'm sick and tired of half-finished docs - let's see if I can push through that one this way ;-/