Commit f7621b11 authored by Amir Goldstein's avatar Amir Goldstein
Browse files

ovl: protect copying of realinode attributes to ovl inode 



ovl_copyattr() may be called concurrently from aio completion context
without any lock and that could lead to overlay inode attributes getting
permanently out of sync with real inode attributes.

Use ovl inode spinlock to protect ovl_copyattr().

Signed-off-by: default avatarAmir Goldstein <amir73il@gmail.com>
parent 389a4a4a

fs/overlayfs/util.c

+2 −0
Original line number Diff line number Diff line
@@ -1403,6 +1403,7 @@ void ovl_copyattr(struct inode *inode) 
	realinode = ovl_i_path_real(inode, &realpath);

	real_idmap = mnt_idmap(realpath.mnt);



	spin_lock(&inode->i_lock);

	vfsuid = i_uid_into_vfsuid(real_idmap, realinode);

	vfsgid = i_gid_into_vfsgid(real_idmap, realinode);
@@ -1413,4 +1414,5 @@ void ovl_copyattr(struct inode *inode) 
	inode_set_mtime_to_ts(inode, inode_get_mtime(realinode));

	inode_set_ctime_to_ts(inode, inode_get_ctime(realinode));

	i_size_write(inode, i_size_read(realinode));

	spin_unlock(&inode->i_lock);

}