tree cbe1a838712a092f7abe49920a09188ec2403578
parent 991ac30d8b30ab6051dff5a7b07d84e6f5efa3a6
author Marco Stornelli <marco.stornelli@gmail.com> 1299319819 +0100
committer Al Viro <viro@zeniv.linux.org.uk> 1299748935 -0500

Check for immutable/append flag in fallocate path

In the fallocate path the kernel doesn't check for the immutable/append
flag. It's possible to have a race condition in this scenario: an
application open a file in read/write and it does something, meanwhile
root set the immutable flag on the file, the application at that point
can call fallocate with success. In addition, we don't allow to do any
unreserve operation on an append only file but only the reserve one.

Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>