diff options
| author | Amir Goldstein <amir73il@gmail.com> | 2017-01-31 10:34:55 +0200 |
|---|---|---|
| committer | Miklos Szeredi <mszeredi@redhat.com> | 2017-02-07 15:05:04 +0100 |
| commit | 9e79b1326302589a035fe20e8cce7c1a7d8333ed (patch) | |
| tree | 80ba2823440ee9f7915b40c43d211e9e0be71d8c | |
| parent | af7bd4dc13093bf1477f370722bbab24cf457b91 (diff) | |
vfs: deny fallocate() on directory
There was an obscure use case of fallocate of directory inode
in the vfs helper with the comment:
"Let individual file system decide if it supports preallocation
for directories or not."
But there is no in-tree file system that implements fallocate
for directory operations.
Deny an attempt to fallocate a directory with EISDIR error.
This change is needed prior to converting sb_start_write()
to file_start_write(), so freeze protection is correctly
handled for cases of fallocate file and blockdev.
Cc: linux-api@vger.kernel.org
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| -rw-r--r-- | fs/open.c | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/fs/open.c b/fs/open.c index 9921f70bc5ca..f9118f4113e7 100644 --- a/fs/open.c +++ b/fs/open.c @@ -301,12 +301,10 @@ int vfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len) if (S_ISFIFO(inode->i_mode)) return -ESPIPE; - /* - * Let individual file system decide if it supports preallocation - * for directories or not. - */ - if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode) && - !S_ISBLK(inode->i_mode)) + if (S_ISDIR(inode->i_mode)) + return -EISDIR; + + if (!S_ISREG(inode->i_mode) && !S_ISBLK(inode->i_mode)) return -ENODEV; /* Check for wrap through zero too */ |