[PATCH] splice: fix problem introduced with inode diet
After the inode slimming patch that unionised i_pipe/i_bdev/i_cdev, it's
no longer enough to check for existance of ->i_pipe to verify that this
is a pipe.
Original patch from Eric Dumazet <dada1@cosmosbay.com>
Final solution suggested by Linus.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/splice.c b/fs/splice.c
index 8d70595..da74583 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -1109,6 +1109,19 @@
EXPORT_SYMBOL(do_splice_direct);
/*
+ * After the inode slimming patch, i_pipe/i_bdev/i_cdev share the same
+ * location, so checking ->i_pipe is not enough to verify that this is a
+ * pipe.
+ */
+static inline struct pipe_inode_info *pipe_info(struct inode *inode)
+{
+ if (S_ISFIFO(inode->i_mode))
+ return inode->i_pipe;
+
+ return NULL;
+}
+
+/*
* Determine where to splice to/from.
*/
static long do_splice(struct file *in, loff_t __user *off_in,
@@ -1119,7 +1132,7 @@
loff_t offset, *off;
long ret;
- pipe = in->f_dentry->d_inode->i_pipe;
+ pipe = pipe_info(in->f_dentry->d_inode);
if (pipe) {
if (off_in)
return -ESPIPE;
@@ -1140,7 +1153,7 @@
return ret;
}
- pipe = out->f_dentry->d_inode->i_pipe;
+ pipe = pipe_info(out->f_dentry->d_inode);
if (pipe) {
if (off_out)
return -ESPIPE;
@@ -1298,7 +1311,7 @@
static long do_vmsplice(struct file *file, const struct iovec __user *iov,
unsigned long nr_segs, unsigned int flags)
{
- struct pipe_inode_info *pipe = file->f_dentry->d_inode->i_pipe;
+ struct pipe_inode_info *pipe;
struct page *pages[PIPE_BUFFERS];
struct partial_page partial[PIPE_BUFFERS];
struct splice_pipe_desc spd = {
@@ -1308,7 +1321,8 @@
.ops = &user_page_pipe_buf_ops,
};
- if (unlikely(!pipe))
+ pipe = pipe_info(file->f_dentry->d_inode);
+ if (!pipe)
return -EBADF;
if (unlikely(nr_segs > UIO_MAXIOV))
return -EINVAL;
@@ -1535,8 +1549,8 @@
static long do_tee(struct file *in, struct file *out, size_t len,
unsigned int flags)
{
- struct pipe_inode_info *ipipe = in->f_dentry->d_inode->i_pipe;
- struct pipe_inode_info *opipe = out->f_dentry->d_inode->i_pipe;
+ struct pipe_inode_info *ipipe = pipe_info(in->f_dentry->d_inode);
+ struct pipe_inode_info *opipe = pipe_info(out->f_dentry->d_inode);
int ret = -EINVAL;
/*