[PATCH] r/o bind mounts: prepare for write access checks: collapse if()
We're shortly going to be adding a bunch more permission checks in these
functions. That requires adding either a bunch of new if() conditions, or
some gotos. This patch collapses existing if()s and uses gotos instead to
prepare for the upcoming changes.
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/namei.c b/fs/namei.c
index 2892e68..7bdceed 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1934,30 +1934,32 @@
{
int error = 0;
char * tmp;
+ struct dentry *dentry;
+ struct nameidata nd;
tmp = getname(pathname);
error = PTR_ERR(tmp);
- if (!IS_ERR(tmp)) {
- struct dentry *dentry;
- struct nameidata nd;
+ if (IS_ERR(tmp))
+ goto out_err;
- error = do_path_lookup(dfd, tmp, LOOKUP_PARENT, &nd);
- if (error)
- goto out;
- dentry = lookup_create(&nd, 1);
- error = PTR_ERR(dentry);
- if (!IS_ERR(dentry)) {
- if (!IS_POSIXACL(nd.dentry->d_inode))
- mode &= ~current->fs->umask;
- error = vfs_mkdir(nd.dentry->d_inode, dentry, mode);
- dput(dentry);
- }
- mutex_unlock(&nd.dentry->d_inode->i_mutex);
- path_release(&nd);
+ error = do_path_lookup(dfd, tmp, LOOKUP_PARENT, &nd);
+ if (error)
+ goto out;
+ dentry = lookup_create(&nd, 1);
+ error = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
+ goto out_unlock;
+
+ if (!IS_POSIXACL(nd.dentry->d_inode))
+ mode &= ~current->fs->umask;
+ error = vfs_mkdir(nd.dentry->d_inode, dentry, mode);
+ dput(dentry);
+out_unlock:
+ mutex_unlock(&nd.dentry->d_inode->i_mutex);
+ path_release(&nd);
out:
- putname(tmp);
- }
-
+ putname(tmp);
+out_err:
return error;
}
@@ -2056,10 +2058,11 @@
mutex_lock_nested(&nd.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
dentry = lookup_hash(&nd);
error = PTR_ERR(dentry);
- if (!IS_ERR(dentry)) {
- error = vfs_rmdir(nd.dentry->d_inode, dentry);
- dput(dentry);
- }
+ if (IS_ERR(dentry))
+ goto exit2;
+ error = vfs_rmdir(nd.dentry->d_inode, dentry);
+ dput(dentry);
+exit2:
mutex_unlock(&nd.dentry->d_inode->i_mutex);
exit1:
path_release(&nd);
@@ -2199,30 +2202,33 @@
int error = 0;
char * from;
char * to;
+ struct dentry *dentry;
+ struct nameidata nd;
from = getname(oldname);
if(IS_ERR(from))
return PTR_ERR(from);
to = getname(newname);
error = PTR_ERR(to);
- if (!IS_ERR(to)) {
- struct dentry *dentry;
- struct nameidata nd;
+ if (IS_ERR(to))
+ goto out_putname;
- error = do_path_lookup(newdfd, to, LOOKUP_PARENT, &nd);
- if (error)
- goto out;
- dentry = lookup_create(&nd, 0);
- error = PTR_ERR(dentry);
- if (!IS_ERR(dentry)) {
- error = vfs_symlink(nd.dentry->d_inode, dentry, from, S_IALLUGO);
- dput(dentry);
- }
- mutex_unlock(&nd.dentry->d_inode->i_mutex);
- path_release(&nd);
+ error = do_path_lookup(newdfd, to, LOOKUP_PARENT, &nd);
+ if (error)
+ goto out;
+ dentry = lookup_create(&nd, 0);
+ error = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
+ goto out_unlock;
+
+ error = vfs_symlink(nd.dentry->d_inode, dentry, from, S_IALLUGO);
+ dput(dentry);
+out_unlock:
+ mutex_unlock(&nd.dentry->d_inode->i_mutex);
+ path_release(&nd);
out:
- putname(to);
- }
+ putname(to);
+out_putname:
putname(from);
return error;
}
@@ -2308,10 +2314,11 @@
goto out_release;
new_dentry = lookup_create(&nd, 0);
error = PTR_ERR(new_dentry);
- if (!IS_ERR(new_dentry)) {
- error = vfs_link(old_nd.dentry, nd.dentry->d_inode, new_dentry);
- dput(new_dentry);
- }
+ if (IS_ERR(new_dentry))
+ goto out_unlock;
+ error = vfs_link(old_nd.dentry, nd.dentry->d_inode, new_dentry);
+ dput(new_dentry);
+out_unlock:
mutex_unlock(&nd.dentry->d_inode->i_mutex);
out_release:
path_release(&nd);