Building upon the success of FreeBSD 5.1, this release includes:

• Full Tier-1 support for single and multiprocessor AMD Athlon64 and Opteron systems.
• Dynamically linked root partition for a smaller installation footprint and better integration with the Name Service Switch subsystem.
• New and improved driver support for IDE, SATA, and 802.11a/b/g devices, and significantly better integration with the ACPI power management subsystem.
• Client support for the Network File System version 4 protocol.
• Experimental first-stage support for multithreaded filtering and forwarding of IP traffic. This also provides the foundation for a fully multi-threaded network stack in the next release of FreeBSD.
• In-box support for the latest Gnome 2.4 and KDE 3.1 desktops.

Security Advisories

A single-byte buffer overflow in realpath(3) was fixed. Although the fix was committed prior to FreeBSD 5.1-RELEASE (and thus 5.1-RELEASE was not affected), it was not noted in the release documentation. See security advisory FreeBSD-SA-03:08.

A bug that could allow the kernel to attempt delivery of invalid signals has been fixed. The bug could have led to a kernel panic or, under some circumstances, unauthorized modification of kernel memory. For more information, see security advisory FreeBSD-SA-03:09.

A bug in the iBCS2 emulation module, which could result in disclosing the contents of kernel memory, has been fixed. This module is not enabled in FreeBSD by default. For more information, see security advisory FreeBSD-SA-03:10.


A buffer management bug in OpenSSH, which could potentially cause a crash, has been fixed. More information can be found in security advisory FreeBSD-SA-03:12.

A buffer overflow in sendmail has been fixed. More information can be found in security advisory FreeBSD-SA-03:13.

A bug that could allow the kernel to cause resource starvation which eventually results in a system panic in the ARP cache code has been fixed. More information can be found in security advisory FreeBSD-SA-03:14.