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8.16. autofs

Updated autofs packages that fix several bugs are now available for Red Hat Enterprise Linux 6.
The autofs utility controls the operation of the automount daemon. The daemon automatically mounts file systems when in use and unmounts them when they are not busy.

Bug Fixes

The am-utils package, which provides automatic mounting of maps in the amd format, is no longer supported in Red Hat Enterprise Linux 6. However, amd-formatted maps are still needed for example when using keys containing the forward slash (/), using wildcard matching for keys, or performing more complex actions after the key is matched. This update adds a parser for amd-formatted maps to the autofs utility.
If an IPv6 link-local address contained the percent sign (%), the autofs utility incorrectly reported the address as invalid. The mount location validity check has been updated, and the incorrect reports no longer occur in the described case.
When checking the mount option string, the automount daemon did not take into account the length of the string, which led to incorrect comparisons. As a consequence, the mount probes did not include NFS version 3 when the "-v" option was used, and under some circumstances, the mounts were not created properly. The option matching has been modified to account for option length, thus fixing this bug.
Due to previous changes to the autofs utility, autofs was not properly handling remote procedure calls (RPC) to probe server availability. Consequently, autofs was not querying the portmapper service for NFS version 2 and NFS version 3 mounts correctly. The RPC handling in autofs has been updated, and autofs now queries host availability properly.
The negative cache timeout was not handled properly by the autofs utility. Consequently, autofs was not correctly reading included automounter maps. This update fixes the handling of the negative cache in autofs.
BZ#1068999, BZ#1081285
The autofs utility did not apply mutual exclusion when using the initialization and termination functions from the OpenLDAP library. As these functions are not thread-safe, a double free error occurred and autofs terminated unexpectedly. This bug has been fixed by adding a mutual exclusion condition for the aforementioned OpenLDAP functions.
The autofs utility did not correctly process the output from the scandir() function. Consequently, autofs could terminate unexpectedly with a segmentation fault. The autofs utility has been modified to correctly read the scandir() output.
If the standard I/O file descriptors were closed by a process that started the autofs utility, autofs, before entering daemon state, could create file descriptor corresponding to one of the standard I/O file descriptors. When autofs entered daemon mode, these file descriptors were closed and autofs terminated unexpectedly. Now, the device control file descriptor is closed after the autofs file system version check and a new descriptor is opened after autofs enters daemon mode.
The autofs utility did not properly check for entries that corresponded to previously failed mount attempts, the so-called "negative entries". Consequently, when the "autofs mount" command was specified with the "browse" option, the autofs utility could create directories that did not correspond to map entries within the corresponding automounter map. With this update, the check for negative map entries has been fixed.
When calling the autofs parser, the scan buffer was sometimes not properly reset for the next scan. Consequently, incorrect success returns occurred for subsequent operations. The autofs utility attempted to add these returned entries, which led to a segmentation fault. This bug has been fixed by adding a function that resets the parse buffer at the start of each map entry scan.
Users of autofs are advised to upgrade to these updated packages, which fix these bugs.