The patch titled
     r/o bind mounts: elevate writer count for chown and friends
has been added to the -mm tree.  Its filename is
     r-o-bind-mounts-elevate-writer-count-for-chown-and-friends.patch

*** Remember to use Documentation/SubmitChecklist when testing your code ***

See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this

------------------------------------------------------
Subject: r/o bind mounts: elevate writer count for chown and friends
From: Dave Hansen <[EMAIL PROTECTED]>

chown/chmod,etc...  don't call permission in the same way that the normal
"open for write" calls do.  They still write to the filesystem, so bump the
write count during these operations.

Signed-off-by: Dave Hansen <[EMAIL PROTECTED]>
Cc: Al Viro <[EMAIL PROTECTED]>
Cc: Christoph Hellwig <[EMAIL PROTECTED]>
Cc: Miklos Szeredi <[EMAIL PROTECTED]>
Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
---

 fs/open.c |   40 ++++++++++++++++++++++++++++++----------
 1 file changed, 30 insertions(+), 10 deletions(-)

diff -puN fs/open.c~r-o-bind-mounts-elevate-writer-count-for-chown-and-friends 
fs/open.c
--- a/fs/open.c~r-o-bind-mounts-elevate-writer-count-for-chown-and-friends
+++ a/fs/open.c
@@ -508,12 +508,12 @@ asmlinkage long sys_fchmod(unsigned int 
 
        audit_inode(NULL, inode);
 
-       err = -EROFS;
-       if (IS_RDONLY(inode))
+       err = mnt_want_write(file->f_vfsmnt);
+       if (err)
                goto out_putf;
        err = -EPERM;
        if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
-               goto out_putf;
+               goto out_drop_write;
        mutex_lock(&inode->i_mutex);
        if (mode == (mode_t) -1)
                mode = inode->i_mode;
@@ -522,6 +522,8 @@ asmlinkage long sys_fchmod(unsigned int 
        err = notify_change(dentry, &newattrs);
        mutex_unlock(&inode->i_mutex);
 
+out_drop_write:
+       mnt_drop_write(file->f_vfsmnt);
 out_putf:
        fput(file);
 out:
@@ -541,13 +543,13 @@ asmlinkage long sys_fchmodat(int dfd, co
                goto out;
        inode = nd.dentry->d_inode;
 
-       error = -EROFS;
-       if (IS_RDONLY(inode))
+       error = mnt_want_write(nd.mnt);
+       if (error)
                goto dput_and_out;
 
        error = -EPERM;
        if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
-               goto dput_and_out;
+               goto out_drop_write;
 
        mutex_lock(&inode->i_mutex);
        if (mode == (mode_t) -1)
@@ -557,6 +559,8 @@ asmlinkage long sys_fchmodat(int dfd, co
        error = notify_change(nd.dentry, &newattrs);
        mutex_unlock(&inode->i_mutex);
 
+out_drop_write:
+       mnt_drop_write(nd.mnt);
 dput_and_out:
        path_release(&nd);
 out:
@@ -579,10 +583,7 @@ static int chown_common(struct dentry * 
                printk(KERN_ERR "chown_common: NULL inode\n");
                goto out;
        }
-       error = -EROFS;
-       if (IS_RDONLY(inode))
-               goto out;
-       error = -EPERM;
+       error = -EPERM;
        if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
                goto out;
        newattrs.ia_valid =  ATTR_CTIME;
@@ -611,7 +612,12 @@ asmlinkage long sys_chown(const char __u
        error = user_path_walk(filename, &nd);
        if (error)
                goto out;
+       error = mnt_want_write(nd.mnt);
+       if (error)
+               goto out_release;
        error = chown_common(nd.dentry, user, group);
+       mnt_drop_write(nd.mnt);
+out_release:
        path_release(&nd);
 out:
        return error;
@@ -631,7 +637,12 @@ asmlinkage long sys_fchownat(int dfd, co
        error = __user_walk_fd(dfd, filename, follow, &nd);
        if (error)
                goto out;
+       error = mnt_want_write(nd.mnt);
+       if (error)
+               goto out_release;
        error = chown_common(nd.dentry, user, group);
+       mnt_drop_write(nd.mnt);
+out_release:
        path_release(&nd);
 out:
        return error;
@@ -645,7 +656,11 @@ asmlinkage long sys_lchown(const char __
        error = user_path_walk_link(filename, &nd);
        if (error)
                goto out;
+       error = mnt_want_write(nd.mnt);
+       if (error)
+               goto out_release;
        error = chown_common(nd.dentry, user, group);
+out_release:
        path_release(&nd);
 out:
        return error;
@@ -662,9 +677,14 @@ asmlinkage long sys_fchown(unsigned int 
        if (!file)
                goto out;
 
+       error = mnt_want_write(file->f_vfsmnt);
+       if (error)
+               goto out_fput;
        dentry = file->f_path.dentry;
        audit_inode(NULL, dentry->d_inode);
        error = chown_common(dentry, user, group);
+       mnt_drop_write(file->f_vfsmnt);
+out_fput:
        fput(file);
 out:
        return error;
_

Patches currently in -mm which might be from [EMAIL PROTECTED] are

r-o-bind-mounts-document-nlink-function.patch
r-o-bind-mounts-filesystem-helpers-for-custom-struct-files.patch
r-o-bind-mounts-r-o-bind-mounts-stub-functions.patch
r-o-bind-mounts-ext3-remove-extra-is_rdonly-check.patch
r-o-bind-mounts-ext4-remove-extra-is_rdonly-check.patch
r-o-bind-mounts-r-o-bind-mounts-elevate-write-count-for-some-ioctls.patch
r-o-bind-mounts-elevate-writer-count-for-chown-and-friends.patch
r-o-bind-mounts-make-access-use-mnt-check.patch
r-o-bind-mounts-elevate-mnt-writers-for-callers-of-vfs_mkdir.patch
r-o-bind-mounts-elevate-write-count-during-entire-ncp_ioctl.patch
r-o-bind-mounts-elevate-write-count-for-link-and-symlink-calls.patch
r-o-bind-mounts-elevate-mount-count-for-extended-attributes.patch
r-o-bind-mounts-elevate-write-count-for-file_update_time.patch
r-o-bind-mounts-mount_is_safe-add-comment.patch
r-o-bind-mounts-unix_find_other-elevate-write-count-for-touch_atime.patch
r-o-bind-mounts-elevate-write-count-over-calls-to-vfs_rename.patch
r-o-bind-mounts-elevate-write-count-files-are-opened.patch
r-o-bind-mounts-nfs-check-mnt-instead-of-sb.patch
r-o-bind-mounts-elevate-writer-count-for-do_sys_truncate.patch
r-o-bind-mounts-elevate-write-count-for-do_utimes.patch
r-o-bind-mounts-elevate-write-count-for-do_sys_utime-and-touch_atime.patch
r-o-bind-mounts-sys_mknodat-elevate-write-count-for-vfs_mknod-create.patch
r-o-bind-mounts-elevate-mnt-writers-for-vfs_unlink-callers.patch
r-o-bind-mounts-do_rmdir-elevate-write-count.patch
r-o-bind-mounts-elevate-writer-count-for-custom-struct_file.patch
r-o-bind-mounts-remove-is_rdonly-from-permission.patch
r-o-bind-mounts-reiser4-remove-is_rdonly-checks.patch

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