From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 4 Oct 2013 01:21:39 +0000 (-0400)
Subject: fuse: rcu-delay freeing fuse_conn
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=dd3e2c55a45fe75f3213b17b74f9a32380f4e84b;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

fuse: rcu-delay freeing fuse_conn

makes ->permission() and ->d_revalidate() safety in RCU mode independent
from vfsmount_lock.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c
index adbfd66b380f..8ca88d716dd3 100644
--- a/fs/fuse/cuse.c
+++ b/fs/fuse/cuse.c
@@ -473,7 +473,7 @@ err:
 static void cuse_fc_release(struct fuse_conn *fc)
 {
 	struct cuse_conn *cc = fc_to_cc(fc);
-	kfree(cc);
+	kfree_rcu(cc, fc.rcu);
 }
 
 /**
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index fe446c222e3f..4715674f050c 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -377,6 +377,8 @@ struct fuse_conn {
 	/** Refcount */
 	atomic_t count;
 
+	struct rcu_head rcu;
+
 	/** The user id for this mount */
 	kuid_t user_id;
 
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 1c15613c64f8..d468643a68b2 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -918,7 +918,7 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
 
 static void fuse_free_conn(struct fuse_conn *fc)
 {
-	kfree(fc);
+	kfree_rcu(fc, rcu);
 }
 
 static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)