[RFC][PATCH 18/30] r/o bind mounts: write counts for link/symlink

Dave Hansen
2008-02-08T22:36:00Z

linux-2.6.git-dave/fs/namei.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff -puN fs/namei.c~r-o-bind-mounts-elevate-write-count-for-link-and-symlink-calls fs/namei.c
--- linux-2.6.git/fs/namei.c~r-o-bind-mounts-elevate-write-count-for-link-and-symlink-calls 2008-02-08 13:04:54.000000000 -0800
+++ linux-2.6.git-dave/fs/namei.c 2008-02-08 13:04:54.000000000 -0800
@@ -2363,7 +2363,12 @@ asmlinkage long sys_symlinkat(const char
if (IS_ERR(dentry))
goto out_unlock;

+ error = mnt_want_write(nd.mnt);
+ if (error)
+ goto out_dput;
error = vfs_symlink(nd.dentry->d_inode, dentry, from, S_IALLUGO);
+ mnt_drop_write(nd.mnt);
+out_dput:
dput(dentry);
out_unlock:
mutex_unlock(&nd.dentry->d_inode->i_mutex);
@@ -2458,7 +2463,12 @@ asmlinkage long sys_linkat(int olddfd, c
error = PTR_ERR(new_dentry);
if (IS_ERR(new_dentry))
goto out_unlock;
+ error = mnt_want_write(nd.mnt);
+ if (error)
+ goto out_dput;
error = vfs_link(old_nd.dentry, nd.dentry->d_inode, new_dentry);
+ mnt_drop_write(nd.mnt);
+out_dput:
dput(new_dentry);
out_unlock:
mutex_unlock(&nd.dentry->d_inode->i_mutex);
_