Commit b2dd05f1 authored by Zhihao Cheng's avatar Zhihao Cheng Committed by Amir Goldstein
Browse files

ovl: let helper ovl_i_path_real() return the realinode 



Let helper ovl_i_path_real() return the realinode to prepare for
checking non-null realinode in RCU walking path.

[msz] Use d_inode_rcu() since we are depending on the consitency
between dentry and inode being non-NULL in an RCU setting.

Signed-off-by: default avatarZhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: default avatarAmir Goldstein <amir73il@gmail.com>
Fixes: ffa5723c ("ovl: store lower path in ovl_inode")
Cc: <stable@vger.kernel.org> # v5.19
Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent 858fd168

fs/overlayfs/overlayfs.h

+1 −1
Original line number Diff line number Diff line
@@ -382,7 +382,7 @@ enum ovl_path_type ovl_path_type(struct dentry *dentry); 
void ovl_path_upper(struct dentry *dentry, struct path *path);

void ovl_path_lower(struct dentry *dentry, struct path *path);

void ovl_path_lowerdata(struct dentry *dentry, struct path *path);

void ovl_i_path_real(struct inode *inode, struct path *path);

struct inode *ovl_i_path_real(struct inode *inode, struct path *path);

enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path);

enum ovl_path_type ovl_path_realdata(struct dentry *dentry, struct path *path);

struct dentry *ovl_dentry_upper(struct dentry *dentry);

fs/overlayfs/util.c

+4 −3
Original line number Diff line number Diff line
@@ -250,7 +250,7 @@ struct dentry *ovl_i_dentry_upper(struct inode *inode) 
	return ovl_upperdentry_dereference(OVL_I(inode));

}



void ovl_i_path_real(struct inode *inode, struct path *path)

struct inode *ovl_i_path_real(struct inode *inode, struct path *path)

{

	path->dentry = ovl_i_dentry_upper(inode);

	if (!path->dentry) {
@@ -259,6 +259,8 @@ void ovl_i_path_real(struct inode *inode, struct path *path) 
	} else {

		path->mnt = ovl_upper_mnt(OVL_FS(inode->i_sb));

	}



	return path->dentry ? d_inode_rcu(path->dentry) : NULL;

}



struct inode *ovl_inode_upper(struct inode *inode)
@@ -1105,8 +1107,7 @@ void ovl_copyattr(struct inode *inode) 
	vfsuid_t vfsuid;

	vfsgid_t vfsgid;



	ovl_i_path_real(inode, &realpath);

	realinode = d_inode(realpath.dentry);

	realinode = ovl_i_path_real(inode, &realpath);

	real_idmap = mnt_idmap(realpath.mnt);



	vfsuid = i_uid_into_vfsuid(real_idmap, realinode);