summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAl Viro <viro@zeniv.linux.org.uk>2012-07-20 02:25:00 +0400
committerAl Viro <viro@zeniv.linux.org.uk>2012-07-29 21:24:15 +0400
commita8104a9fcdeb82e22d7acd55fca20746581067d3 (patch)
tree3036dae685f9b12a878dd02e439f0050114d7745
parent8e4bfca1d1f0de62301dd223675717e7a5f63a27 (diff)
downloadlinux-a8104a9fcdeb82e22d7acd55fca20746581067d3.tar.xz
pull mnt_want_write()/mnt_drop_write() into kern_path_create()/done_path_create() resp.
One side effect - attempt to create a cross-device link on a read-only fs fails with EROFS instead of EXDEV now. Makes more sense, POSIX allows, etc. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-rw-r--r--fs/namei.c57
-rw-r--r--fs/ocfs2/refcounttree.c7
-rw-r--r--net/unix/af_unix.c4
3 files changed, 18 insertions, 50 deletions
diff --git a/fs/namei.c b/fs/namei.c
index cf362dc9d1fd..a3fb78fd70d2 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2865,10 +2865,11 @@ struct dentry *kern_path_create(int dfd, const char *pathname, struct path *path
mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
dentry = lookup_hash(&nd);
if (IS_ERR(dentry))
- goto fail;
+ goto unlock;
+ error = -EEXIST;
if (dentry->d_inode)
- goto eexist;
+ goto fail;
/*
* Special case - lookup gave negative, but... we had foo/bar/
* From the vfs_mknod() POV we just have a negative dentry -
@@ -2876,16 +2877,18 @@ struct dentry *kern_path_create(int dfd, const char *pathname, struct path *path
* been asking for (non-existent) directory. -ENOENT for you.
*/
if (unlikely(!is_dir && nd.last.name[nd.last.len])) {
- dput(dentry);
- dentry = ERR_PTR(-ENOENT);
+ error = -ENOENT;
goto fail;
}
+ error = mnt_want_write(nd.path.mnt);
+ if (error)
+ goto fail;
*path = nd.path;
return dentry;
-eexist:
- dput(dentry);
- dentry = ERR_PTR(-EEXIST);
fail:
+ dput(dentry);
+ dentry = ERR_PTR(error);
+unlock:
mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
out:
path_put(&nd.path);
@@ -2897,6 +2900,7 @@ void done_path_create(struct path *path, struct dentry *dentry)
{
dput(dentry);
mutex_unlock(&path->dentry->d_inode->i_mutex);
+ mnt_drop_write(path->mnt);
path_put(path);
}
EXPORT_SYMBOL(done_path_create);
@@ -2974,12 +2978,9 @@ SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode,
if (!IS_POSIXACL(path.dentry->d_inode))
mode &= ~current_umask();
- error = mnt_want_write(path.mnt);
- if (error)
- goto out_dput;
error = security_path_mknod(&path, dentry, mode, dev);
if (error)
- goto out_drop_write;
+ goto out;
switch (mode & S_IFMT) {
case 0: case S_IFREG:
error = vfs_create(path.dentry->d_inode,dentry,mode,true);
@@ -2992,11 +2993,8 @@ SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode,
error = vfs_mknod(path.dentry->d_inode,dentry,mode,0);
break;
}
-out_drop_write:
- mnt_drop_write(path.mnt);
-out_dput:
+out:
done_path_create(&path, dentry);
-
return error;
}
@@ -3042,16 +3040,9 @@ SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode)
if (!IS_POSIXACL(path.dentry->d_inode))
mode &= ~current_umask();
- error = mnt_want_write(path.mnt);
- if (error)
- goto out_dput;
error = security_path_mkdir(&path, dentry, mode);
- if (error)
- goto out_drop_write;
- error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
-out_drop_write:
- mnt_drop_write(path.mnt);
-out_dput:
+ if (!error)
+ error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
done_path_create(&path, dentry);
return error;
}
@@ -3326,16 +3317,9 @@ SYSCALL_DEFINE3(symlinkat, const char __user *, oldname,
if (IS_ERR(dentry))
goto out_putname;
- error = mnt_want_write(path.mnt);
- if (error)
- goto out_dput;
error = security_path_symlink(&path, dentry, from);
- if (error)
- goto out_drop_write;
- error = vfs_symlink(path.dentry->d_inode, dentry, from);
-out_drop_write:
- mnt_drop_write(path.mnt);
-out_dput:
+ if (!error)
+ error = vfs_symlink(path.dentry->d_inode, dentry, from);
done_path_create(&path, dentry);
out_putname:
putname(from);
@@ -3436,15 +3420,10 @@ SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname,
error = -EXDEV;
if (old_path.mnt != new_path.mnt)
goto out_dput;
- error = mnt_want_write(new_path.mnt);
- if (error)
- goto out_dput;
error = security_path_link(old_path.dentry, &new_path, new_dentry);
if (error)
- goto out_drop_write;
+ goto out_dput;
error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry);
-out_drop_write:
- mnt_drop_write(new_path.mnt);
out_dput:
done_path_create(&new_path, new_dentry);
out:
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index 23cf78f68503..30a055049e16 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -4466,16 +4466,9 @@ int ocfs2_reflink_ioctl(struct inode *inode,
goto out_dput;
}
- error = mnt_want_write(new_path.mnt);
- if (error) {
- mlog_errno(error);
- goto out_dput;
- }
-
error = ocfs2_vfs_reflink(old_path.dentry,
new_path.dentry->d_inode,
new_dentry, preserve);
- mnt_drop_write(new_path.mnt);
out_dput:
done_path_create(&new_path, new_dentry);
out:
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index e8239540683a..88ab72820b9f 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -876,15 +876,11 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
*/
mode = S_IFSOCK |
(SOCK_INODE(sock)->i_mode & ~current_umask());
- err = mnt_want_write(path.mnt);
- if (err)
- goto out_mknod_dput;
err = security_path_mknod(&path, dentry, mode, 0);
if (err)
goto out_mknod_drop_write;
err = vfs_mknod(path.dentry->d_inode, dentry, mode, 0);
out_mknod_drop_write:
- mnt_drop_write(path.mnt);
if (err)
goto out_mknod_dput;
mntget(path.mnt);