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| author | Changli Gao <xiaosuo@gmail.com> | 2009-11-04 09:09:52 +0100 |
|---|---|---|
| committer | Jens Axboe <jens.axboe@oracle.com> | 2009-11-04 09:09:52 +0100 |
| commit | cc56f7de7f00d188c7c4da1e9861581853b9e92f (patch) | |
| tree | 4794c8e5b7c7aec176f695dfc9d723d4a73e3ba9 | |
| parent | f21121cde6e617b90cd03ce083652ca543004dc2 (diff) | |
| download | lwn-cc56f7de7f00d188c7c4da1e9861581853b9e92f.tar.gz lwn-cc56f7de7f00d188c7c4da1e9861581853b9e92f.zip | |
sendfile(): check f_op.splice_write() rather than f_op.sendpage()
sendfile(2) was reworked with the splice infrastructure, but it still
checks f_op.sendpage() instead of f_op.splice_write() wrongly. Although
if f_op.sendpage() exists, f_op.splice_write() always exists at the same
time currently, the assumption will be broken in future silently. This
patch also brings a side effect: sendfile(2) can work with any output
file. Some security checks related to f_op are added too.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| -rw-r--r-- | fs/read_write.c | 2 | ||||
| -rw-r--r-- | fs/splice.c | 24 |
2 files changed, 15 insertions, 11 deletions
diff --git a/fs/read_write.c b/fs/read_write.c index 3ac28987f22a..b7f4a1f94d48 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -826,8 +826,6 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, if (!(out_file->f_mode & FMODE_WRITE)) goto fput_out; retval = -EINVAL; - if (!out_file->f_op || !out_file->f_op->sendpage) - goto fput_out; in_inode = in_file->f_path.dentry->d_inode; out_inode = out_file->f_path.dentry->d_inode; retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count); diff --git a/fs/splice.c b/fs/splice.c index 7394e9e17534..39208663aaf1 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -648,9 +648,11 @@ static int pipe_to_sendpage(struct pipe_inode_info *pipe, ret = buf->ops->confirm(pipe, buf); if (!ret) { more = (sd->flags & SPLICE_F_MORE) || sd->len < sd->total_len; - - ret = file->f_op->sendpage(file, buf->page, buf->offset, - sd->len, &pos, more); + if (file->f_op && file->f_op->sendpage) + ret = file->f_op->sendpage(file, buf->page, buf->offset, + sd->len, &pos, more); + else + ret = -EINVAL; } return ret; @@ -1068,8 +1070,9 @@ static long do_splice_from(struct pipe_inode_info *pipe, struct file *out, if (unlikely(ret < 0)) return ret; - splice_write = out->f_op->splice_write; - if (!splice_write) + if (out->f_op && out->f_op->splice_write) + splice_write = out->f_op->splice_write; + else splice_write = default_file_splice_write; return splice_write(pipe, out, ppos, len, flags); @@ -1093,8 +1096,9 @@ static long do_splice_to(struct file *in, loff_t *ppos, if (unlikely(ret < 0)) return ret; - splice_read = in->f_op->splice_read; - if (!splice_read) + if (in->f_op && in->f_op->splice_read) + splice_read = in->f_op->splice_read; + else splice_read = default_file_splice_read; return splice_read(in, ppos, pipe, len, flags); @@ -1316,7 +1320,8 @@ static long do_splice(struct file *in, loff_t __user *off_in, if (off_in) return -ESPIPE; if (off_out) { - if (out->f_op->llseek == no_llseek) + if (!out->f_op || !out->f_op->llseek || + out->f_op->llseek == no_llseek) return -EINVAL; if (copy_from_user(&offset, off_out, sizeof(loff_t))) return -EFAULT; @@ -1336,7 +1341,8 @@ static long do_splice(struct file *in, loff_t __user *off_in, if (off_out) return -ESPIPE; if (off_in) { - if (in->f_op->llseek == no_llseek) + if (!in->f_op || !in->f_op->llseek || + in->f_op->llseek == no_llseek) return -EINVAL; if (copy_from_user(&offset, off_in, sizeof(loff_t))) return -EFAULT; |