Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse

Pull fuse updates from Miklos Szeredi:
 "Support for pid namespaces from Seth and refcount_t work from Elena"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: Add support for pid namespaces
  fuse: convert fuse_conn.count from atomic_t to refcount_t
  fuse: convert fuse_req.count from atomic_t to refcount_t
  fuse: convert fuse_file.count from atomic_t to refcount_t

1 files changed, 15 insertions, 9 deletions

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index c2d7f3a92679..c16d00e53264 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -20,6 +20,7 @@
 #include <linux/pipe_fs_i.h>
 #include <linux/swap.h>
 #include <linux/splice.h>
+#include <linux/sched.h>
 
 MODULE_ALIAS_MISCDEV(FUSE_MINOR);
 MODULE_ALIAS("devname:fuse");
@@ -45,7 +46,7 @@ static void fuse_request_init(struct fuse_req *req, struct page **pages,
 	INIT_LIST_HEAD(&req->list);
 	INIT_LIST_HEAD(&req->intr_entry);
 	init_waitqueue_head(&req->waitq);
-	atomic_set(&req->count, 1);
+	refcount_set(&req->count, 1);
 	req->pages = pages;
 	req->page_descs = page_descs;
 	req->max_pages = npages;
@@ -102,21 +103,20 @@ void fuse_request_free(struct fuse_req *req)
 
 void __fuse_get_request(struct fuse_req *req)
 {
-	atomic_inc(&req->count);
+	refcount_inc(&req->count);
 }
 
 /* Must be called with > 1 refcount */
 static void __fuse_put_request(struct fuse_req *req)
 {
-	BUG_ON(atomic_read(&req->count) < 2);
-	atomic_dec(&req->count);
+	refcount_dec(&req->count);
 }
 
-static void fuse_req_init_context(struct fuse_req *req)
+static void fuse_req_init_context(struct fuse_conn *fc, struct fuse_req *req)
 {
 	req->in.h.uid = from_kuid_munged(&init_user_ns, current_fsuid());
 	req->in.h.gid = from_kgid_munged(&init_user_ns, current_fsgid());
-	req->in.h.pid = current->pid;
+	req->in.h.pid = pid_nr_ns(task_pid(current), fc->pid_ns);
 }
 
 void fuse_set_initialized(struct fuse_conn *fc)
@@ -163,7 +163,7 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
 		goto out;
 	}
 
-	fuse_req_init_context(req);
+	fuse_req_init_context(fc, req);
 	__set_bit(FR_WAITING, &req->flags);
 	if (for_background)
 		__set_bit(FR_BACKGROUND, &req->flags);
@@ -256,7 +256,7 @@ struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
 	if (!req)
 		req = get_reserved_req(fc, file);
 
-	fuse_req_init_context(req);
+	fuse_req_init_context(fc, req);
 	__set_bit(FR_WAITING, &req->flags);
 	__clear_bit(FR_BACKGROUND, &req->flags);
 	return req;
@@ -264,7 +264,7 @@ struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
 
 void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
 {
-	if (atomic_dec_and_test(&req->count)) {
+	if (refcount_dec_and_test(&req->count)) {
 		if (test_bit(FR_BACKGROUND, &req->flags)) {
 			/*
 			 * We get here in the unlikely case that a background
@@ -1222,6 +1222,9 @@ static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file,
 	struct fuse_in *in;
 	unsigned reqsize;
 
+	if (task_active_pid_ns(current) != fc->pid_ns)
+		return -EIO;
+
  restart:
 	spin_lock(&fiq->waitq.lock);
 	err = -EAGAIN;
@@ -1820,6 +1823,9 @@ static ssize_t fuse_dev_do_write(struct fuse_dev *fud,
 	struct fuse_req *req;
 	struct fuse_out_header oh;
 
+	if (task_active_pid_ns(current) != fc->pid_ns)
+		return -EIO;
+
 	if (nbytes < sizeof(struct fuse_out_header))
 		return -EINVAL;