Red Hat 5: RHSA-2011:0999-01 Moderate: rsync Security Issue

rsync is a program for synchronizing files over a network.
A flaw was found in the way the rsync daemon handled the "filter", "exclude", and "exclude from" options, used for hiding files and preventing access to them from rsync clients. A remote attacker could use this flaw to bypass those restrictions by using certain command line options and symbolic links, allowing the attacker to overwrite those files if they knew their file names and had write access to them. (CVE-2007-6200)
Note: This issue only affected users running rsync as a writable daemon: "read only" set to "false" in the rsync configuration file (for example, "/etc/rsyncd.conf"). By default, this option is set to "true".
This update also fixes the following bugs:
* The rsync package has been upgraded to upstream version 3.0.6, which provides a number of bug fixes and enhancements over the previous version. (BZ#339971)
* When running an rsync daemon that was receiving files, a deferred info, error or log message could have been sent directly to the sender instead of being handled by the "rwrite()" function in the generator. Also, under certain circumstances, a deferred info or error message from the receiver could have bypassed the log file and could have been sent only to the client process. As a result, an "unexpected tag 3" fatal error could have been displayed. These problems have been fixed in this update so that an rsync daemon receiving files now works as expected. (BZ#471182)
* Prior to this update, the rsync daemon called a number of timezone-using functions after doing a chroot. As a result, certain C libraries were unable to generate proper timestamps from inside a chrooted daemon. This bug has been fixed in this update so that the rsync daemon now calls the respective timezone-using functions prior to doing a chroot, and proper timestamps are now generated as expected. (BZ#575022)
* When running rsync under a non-root user with the "-A" ("--acls") option and without using the "--numeric-ids" option, if there was an Access Control List (ACL) that included a group entry for a group that the respective user was not a member of on the receiving side, the "acl_set_file()" function returned an invalid argument value ("EINVAL"). This was caused by rsync mistakenly mapping the group name to the Group ID "GID_NONE" ("-1"), which failed. The bug has been fixed in this update so that no invalid argument is returned and rsync works as expected. (BZ#616093)
* When creating a sparse file that was zero blocks long, the "rsync - --sparse" command did not properly truncate the sparse file at the end of the copy transaction. As a result, the file size was bigger than expected. This bug has been fixed in this update by properly truncating the file so that rsync now copies such files as expected. (BZ#530866)
* Under certain circumstances, when using rsync in daemon mode, rsync generator instances could have entered an infinitive loop, trying to write an error message for the receiver to an invalid socket. This problem has been fixed in this update by adding a new sibling message: when the receiver is reporting a socket-read error, the generator will notice this fact and avoid writing an error message down the socket, allowing it to close down gracefully when the pipe from the receiver closes. (BZ#690148)
* Prior to this update, there were missing deallocations found in the "start_client()" function. This bug has been fixed in this update and no longer occurs. (BZ#700450)
All users of rsync are advised to upgrade to this updated package, which resolves these issues and adds enhancements.