iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

proc: don't allow async path resolution of /proc/thread-self components

Browse Source 
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>
This commit is contained in:
Jens Axboe 2021-02-14 13:21:43 -07:00 committed by Greg Kroah-Hartman
parent b7cd9711a1
commit 13fb0e1ecf
2 changed files with 8 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
fs/proc/self.c
View File

@ -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)

7
fs/proc/thread_self.c
View File

@ -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);