Re: [syzbot] [jffs2?] possible deadlock in jffs2_do_clear_inode (2)

[Edward Adam Davis <eadavis@sina.com>]

From: Edward Aadm Davis <eadavis@sina.com>

#syz test: upstream 50d05c7c76c9

diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index 6ada8369a762..59972e03685d 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -256,6 +256,7 @@ struct inode *jffs2_iget(struct super_block *sb, unsigned long ino)
 	struct jffs2_sb_info *c;
 	struct jffs2_raw_inode latest_node;
 	union jffs2_device_node jdev;
+	unsigned int nofs_flag;
 	struct inode *inode;
 	dev_t rdev = 0;
 	int ret;
@@ -274,7 +275,9 @@ struct inode *jffs2_iget(struct super_block *sb, unsigned long ino)
 	jffs2_init_inode_info(f);
 	mutex_lock(&f->sem);
 
+	nofs_flag = memalloc_nofs_save();
 	ret = jffs2_do_read_inode(c, f, inode->i_ino, &latest_node);
+	memalloc_nofs_restore(nofs_flag);
 	if (ret)
 		goto error;