RHBA-2010:0523 - Bug Fix Advisory

Topic

Updated crash packages that fix various bugs are now available.

Description

crash is a self-contained tool that can be used to investigate live systems,
kernel core dumps created from the netdump, diskdump and kdump packages from Red
Hat Linux, the mcore kernel patch offered by Mission Critical Linux, or the LKCD
kernel patch.

These updated packages fix the following bugs:

• the "bt" subcommand of the crash tool occasionally did not output the

backtrace correctly. The error appeared in x86_64 NMI-interrupted tasks which
had not yet switched their stack pointer from the user-space stack to the kernel
stack. This issue has been resolved. (BZ#601081)

• a segmentation violation happened when running the "mach -m" command option on

x86 or x86_64 systems whose BIOS-provided e820 map contained an EFI-related
memory type value that has previously not been mapped to an E820 type. This
issue has been resolved. (BZ#601082).

• the "kmem -s list" subcommand in crash couldn't read the kmem_cache_s.name

string. This issue has been resolved. The list now skips the list_head and only
displays the actual kmem_cache names/addresses. (BZ#601084)

• if a ppc64 kernel was booted with "smt-enabled=off", the initial system banner

and the "sys" and "mach" commands displayed an incorrect CPU count. They have
been changed to display the number of cpus online. (BZ#601088)

• the "bt" subcommand of crash could not resolve the stack trace when an x86

NMI-interrupted task had just entered the kernel from user-space, but had not
yet called the requested system call function. The same issue occurred when the
resumption EIP address value of a newly forked x86 task was set to the
"ret_from_fork" entry point by copy_thread(). This issue has been resolved in
both cases. (BZ#601089)

Solution

All users of crash are advised to upgrade to these updated packages, which
resolve these issues.

Before applying this update, make sure all previously-released errata relevant
to your system have been applied.

This update is available via the Red Hat Network. Details on how to use the Red
Hat Network to apply this update are available at
http://kbase.redhat.com/faq/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 601081 - [5.5] Bt subcommand of crash occasionally does not output the backtrace normally.
• BZ - 601082 - 'mach -m' causes segmentation fault when analysing live system
• BZ - 601084 - "kmem -s list" sub-commands in crash utility doesn't work
• BZ - 601088 - crash tool shows wrong CPU totality when smt=off on RHEL5.5
• BZ - 601089 - [5.5] backtrace subcommand of crash command fails.

CVEs

(none)

References

(none)