diff options
| author | Jens Axboe <axboe@kernel.dk> | 2021-02-14 13:21:43 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-04 12:15:38 +0100 |
| commit | d918c87e744cd63bacea2f6b080d47886148edd9 (patch) | |
| tree | cd32a6d6a234b83fe97ea783bb9fb6e4850acf4a | |
| parent | 9dcb3e36fb23c0ef607b7249feb500b88330fc40 (diff) | |
proc: don't allow async path resolution of /proc/thread-self components
commit 0d4370cfe36b7f1719123b621a4ec4d9c7a25f89 upstream.
If this is attempted by an io-wq kthread, then return -EOPNOTSUPP as we
don't currently support that. Once we can get task_pid_ptr() doing the
right thing, then this can go away again.
Use PF_IO_WORKER for this to speciically target the io_uring workers.
Modify the /proc/self/ check to use PF_IO_WORKER as well.
Cc: stable@vger.kernel.org
Fixes: 8d4c3e76e3be ("proc: don't allow async path resolution of /proc/self components")
Reported-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/proc/self.c | 2 | ||||
| -rw-r--r-- | fs/proc/thread_self.c | 7 |
2 files changed, 8 insertions, 1 deletions
diff --git a/fs/proc/self.c b/fs/proc/self.c index cc71ce3466dc..a4012154e109 100644 --- a/fs/proc/self.c +++ b/fs/proc/self.c @@ -20,7 +20,7 @@ static const char *proc_self_get_link(struct dentry *dentry, * Not currently supported. Once we can inherit all of struct pid, * we can allow this. */ - if (current->flags & PF_KTHREAD) + if (current->flags & PF_IO_WORKER) return ERR_PTR(-EOPNOTSUPP); if (!tgid) diff --git a/fs/proc/thread_self.c b/fs/proc/thread_self.c index a553273fbd41..d56681d86d28 100644 --- a/fs/proc/thread_self.c +++ b/fs/proc/thread_self.c @@ -17,6 +17,13 @@ static const char *proc_thread_self_get_link(struct dentry *dentry, pid_t pid = task_pid_nr_ns(current, ns); char *name; + /* + * Not currently supported. Once we can inherit all of struct pid, + * we can allow this. + */ + if (current->flags & PF_IO_WORKER) + return ERR_PTR(-EOPNOTSUPP); + if (!pid) return ERR_PTR(-ENOENT); name = kmalloc(10 + 6 + 10 + 1, dentry ? GFP_KERNEL : GFP_ATOMIC); |