From c71922c55f7a5b0031574d9e07c39e83ef204ba4 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Fri, 28 Jun 2013 09:52:57 +1000 Subject: [PATCH] autofs4: translate pids to the right namespace for the daemon The PID and the TGID of the process triggering the mount are sent to the daemon. Currently the global pid values are sent (ones valid in the initial pid namespace) but this is wrong if the autofs daemon itself is not running in the initial pid namespace. So send the pid values that are valid in the namespace of the autofs daemon. The namespace to use is taken from the oz_pgrp pid pointer, which was set at mount time to the mounting process' pid namespace. If the pid translation fails (the triggering process is in an unrelated pid namespace) then the automount fails with ENOENT. Signed-off-by: Miklos Szeredi Acked-by: Serge Hallyn Cc: Eric Biederman Cc: Ian Kent Cc: Oleg Nesterov Signed-off-by: Andrew Morton --- fs/autofs4/waitq.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c index 3db70dae40d3..309ca6bcbb09 100644 --- a/fs/autofs4/waitq.c +++ b/fs/autofs4/waitq.c @@ -353,11 +353,23 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry, struct qstr qstr; char *name; int status, ret, type; + pid_t pid; + pid_t tgid; /* In catatonic mode, we don't wait for nobody */ if (sbi->catatonic) return -ENOENT; + /* + * Try translating pids to the namespace of the daemon. + * + * Zero means failure: we are in an unrelated pid namespace. + */ + pid = task_pid_nr_ns(current, ns_of_pid(sbi->oz_pgrp)); + tgid = task_tgid_nr_ns(current, ns_of_pid(sbi->oz_pgrp)); + if (pid == 0 || tgid == 0) + return -ENOENT; + if (!dentry->d_inode) { /* * A wait for a negative dentry is invalid for certain @@ -423,8 +435,8 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry, wq->ino = autofs4_get_ino(sbi); wq->uid = current_uid(); wq->gid = current_gid(); - wq->pid = current->pid; - wq->tgid = current->tgid; + wq->pid = pid; + wq->tgid = tgid; wq->status = -EINTR; /* Status return if interrupted */ wq->wait_ctr = 2; mutex_unlock(&sbi->wq_mutex); -- 2.39.5