From be62a1a8fd116f5cd9e53726601f970e16e17558 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Sat, 26 Mar 2016 16:14:39 -0400 Subject: nfs: use file_dentry() NFS may be used as lower layer of overlayfs and accessing f_path.dentry can lead to a crash. Fix by replacing direct access of file->f_path.dentry with the file_dentry() accessor, which will always return a native object. Fixes: 4bacc9c9234c ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay") Signed-off-by: Miklos Szeredi Tested-by: Goldwyn Rodrigues Acked-by: Trond Myklebust Signed-off-by: Theodore Ts'o Cc: # v4.2 Cc: David Howells Cc: Al Viro --- fs/nfs/nfs4file.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/nfs/nfs4file.c') diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index 57ca1c8..2a9ff14 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -26,7 +26,7 @@ static int nfs4_file_open(struct inode *inode, struct file *filp) { struct nfs_open_context *ctx; - struct dentry *dentry = filp->f_path.dentry; + struct dentry *dentry = file_dentry(filp); struct dentry *parent = NULL; struct inode *dir; unsigned openflags = filp->f_flags; @@ -57,7 +57,7 @@ nfs4_file_open(struct inode *inode, struct file *filp) parent = dget_parent(dentry); dir = d_inode(parent); - ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode); + ctx = alloc_nfs_open_context(file_dentry(filp), filp->f_mode); err = PTR_ERR(ctx); if (IS_ERR(ctx)) goto out; -- cgit v1.1