From 7f3d4ee108c184ab215036051087aaaaa8de7661 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 7 May 2008 09:22:39 +0200 Subject: [PATCH] vfs: splice remove_suid() cleanup generic_file_splice_write() duplicates remove_suid() just because it doesn't hold i_mutex. But it grabs i_mutex inside splice_from_pipe() anyway, so this is rather pointless. Move locking to generic_file_splice_write() and call remove_suid() and __splice_from_pipe() instead. Signed-off-by: Miklos Szeredi Signed-off-by: Jens Axboe --- fs/splice.c | 29 +++++++++++++---------------- include/linux/fs.h | 1 - mm/filemap.c | 2 +- 3 files changed, 14 insertions(+), 18 deletions(-) diff --git a/fs/splice.c b/fs/splice.c index 633f58ebfb72..cece15b4ef72 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -811,24 +811,19 @@ generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out, { struct address_space *mapping = out->f_mapping; struct inode *inode = mapping->host; - int killsuid, killpriv; + struct splice_desc sd = { + .total_len = len, + .flags = flags, + .pos = *ppos, + .u.file = out, + }; ssize_t ret; - int err = 0; - killpriv = security_inode_need_killpriv(out->f_path.dentry); - killsuid = should_remove_suid(out->f_path.dentry); - if (unlikely(killsuid || killpriv)) { - mutex_lock(&inode->i_mutex); - if (killpriv) - err = security_inode_killpriv(out->f_path.dentry); - if (!err && killsuid) - err = __remove_suid(out->f_path.dentry, killsuid); - mutex_unlock(&inode->i_mutex); - if (err) - return err; - } - - ret = splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_file); + inode_double_lock(inode, pipe->inode); + ret = remove_suid(out->f_path.dentry); + if (likely(!ret)) + ret = __splice_from_pipe(pipe, &sd, pipe_to_file); + inode_double_unlock(inode, pipe->inode); if (ret > 0) { unsigned long nr_pages; @@ -840,6 +835,8 @@ generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out, * sync it. */ if (unlikely((out->f_flags & O_SYNC) || IS_SYNC(inode))) { + int err; + mutex_lock(&inode->i_mutex); err = generic_osync_inode(inode, mapping, OSYNC_METADATA|OSYNC_DATA); diff --git a/include/linux/fs.h b/include/linux/fs.h index 7e0fa9e64479..f413085f748e 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1816,7 +1816,6 @@ extern void iget_failed(struct inode *); extern void clear_inode(struct inode *); extern void destroy_inode(struct inode *); extern struct inode *new_inode(struct super_block *); -extern int __remove_suid(struct dentry *, int); extern int should_remove_suid(struct dentry *); extern int remove_suid(struct dentry *); diff --git a/mm/filemap.c b/mm/filemap.c index 239d36163bbe..2dead9adf8b7 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1655,7 +1655,7 @@ int should_remove_suid(struct dentry *dentry) } EXPORT_SYMBOL(should_remove_suid); -int __remove_suid(struct dentry *dentry, int kill) +static int __remove_suid(struct dentry *dentry, int kill) { struct iattr newattrs;