diff options
| author | Miklos Szeredi <mszeredi@redhat.com> | 2016-03-26 16:14:39 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-04-20 15:45:24 +0900 |
| commit | 385e5edc295f7feeef00c64f2f5c14b3530940ef (patch) | |
| tree | fb6deb7466916b1e2545ce20f5c89cedef90b77d | |
| parent | 0a20aeaa907f53bbb9cc881c6e4f8b3bb601bb27 (diff) | |
| download | lwn-385e5edc295f7feeef00c64f2f5c14b3530940ef.tar.gz lwn-385e5edc295f7feeef00c64f2f5c14b3530940ef.zip | |
nfs: use file_dentry()
commit be62a1a8fd116f5cd9e53726601f970e16e17558 upstream.
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 <mszeredi@redhat.com>
Tested-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Acked-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/nfs/dir.c | 6 | ||||
| -rw-r--r-- | fs/nfs/inode.c | 2 | ||||
| -rw-r--r-- | fs/nfs/nfs4file.c | 4 |
3 files changed, 6 insertions, 6 deletions
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 9cce67043f92..7ded17764754 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -377,7 +377,7 @@ int nfs_readdir_xdr_filler(struct page **pages, nfs_readdir_descriptor_t *desc, again: timestamp = jiffies; gencount = nfs_inc_attr_generation_counter(); - error = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred, entry->cookie, pages, + error = NFS_PROTO(inode)->readdir(file_dentry(file), cred, entry->cookie, pages, NFS_SERVER(inode)->dtsize, desc->plus); if (error < 0) { /* We requested READDIRPLUS, but the server doesn't grok it */ @@ -560,7 +560,7 @@ int nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *en count++; if (desc->plus != 0) - nfs_prime_dcache(desc->file->f_path.dentry, entry); + nfs_prime_dcache(file_dentry(desc->file), entry); status = nfs_readdir_add_to_array(entry, page); if (status != 0) @@ -864,7 +864,7 @@ static bool nfs_dir_mapping_need_revalidate(struct inode *dir) */ static int nfs_readdir(struct file *file, struct dir_context *ctx) { - struct dentry *dentry = file->f_path.dentry; + struct dentry *dentry = file_dentry(file); struct inode *inode = d_inode(dentry); nfs_readdir_descriptor_t my_desc, *desc = &my_desc; diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 86faecf8f328..847b678af4f0 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -940,7 +940,7 @@ int nfs_open(struct inode *inode, struct file *filp) { struct nfs_open_context *ctx; - ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode); + ctx = alloc_nfs_open_context(file_dentry(filp), filp->f_mode); if (IS_ERR(ctx)) return PTR_ERR(ctx); nfs_file_set_open_context(filp, ctx); diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index 57ca1c8039c1..2a9ff14cfb3b 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; |