RHBA-2015:1827 - Bug Fix Advisory

Topic

Updated kernel packages that fix several bugs are now available for Red Hat Enterprise Linux 6.

Description

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Bugs:

• A previous change in the get_swap_page() locking removed the use of the swap_lock spinlock. This could cause nr_swap_pages corruption and invalid SwapFree information in the /proc/meminfo file, where the size of SwapFree could exceed the size of SwapTotal. This update uses an atomic variable for nr_swap_pages, and the size of SwapFree in /proc/meminfo is now correct. (BZ#1259362)
• When logging in as a user and trying to mount a share using the "cd" command, the UID and GID autofs additional variables previously took incorrect values, taking root UID and GID instead of user's UID and GID. The bug in the assignment of uid and gid mount requests has been fixed, and UID and GID now get the correct values with autofs configuration on Red Hat Enterprise Linux 6.7. (BZ#1258581)
• Previously, the attach_task_by_pid() function in some cases raced with the exiting thread and tried to lock or unlock the already freed group_rwsem member of the signal_struct list. As a consequence, a kernel crash could occur. This update adds the cgroup_threadgroup_rwsem variable, which fixes this bug and prevents the kernel crash from occurring in this scenario. (BZ#1246081)
• Previously, the vmxnet3 driver napi poll implementation used rx descriptor count for the napi poll budget. This allowed to return from napi poll halfway through recieving a fragmented packet if the budget threshold was reached. This behavior caused a kernel panic(BUG_ON) if previous napi poll ended with skb allocation failure and the end of packet was not reached. This bug has been fixed by only counting whole received packets in the napi poll rather than the rx descriptor count. As a result, the aforementioned kernel panic no longer occurs. (BZ#1246092)
• Due to the renaming of the VLAN_GROUP_ARRAY_LEN preprocessor macro, the kernel API for 3rd party modules changed in an incompatible way. As a consequence, compiling the vmxnet3 driver in vmware-tools failed. This update adds a definition of the VLAN_GROUP_ARRAY_LEN macro, and vmxnet3 now succeeds to compile. (BZ#1242145)
• Due to the incorrect length of the FCP_RSP_INFO field, parts of the field could be copied, and "st" and "sg" drivers thus did not work correctly. With this update, the FCP protocol related code has been updated, and "st" and "sg" now work as expected. (BZ#1253728)
• Previously, driving the crypto adapter under high pressure workload with long running cryptographic requests led to performance degradations of the crypto adapter or, in some cases, the crypto adapter entered recovery mode. As a consequence, an Adjunct Processor (AP) queue reset was triggered to recover and reinitialize the AP queue. Due to the different hardware behavior, the reset could be delayed and interrupts were not re-enabled. Now, the RAPQ (queue reset) and AQIC (interrupt control) commands are treated fully asynchronously, and the device driver checks the reset and interrupt states so that it can handle the AP queue reinitialization properly. (BZ#1253729)
• Prior to this update, multiple instances trying to copy the same file triggered a race condition in the perf buildid-cache that could truncate system libraries and other files. With this update, unique temporary files are used when copying to the buildid directory to prevent the aforementioned race condition from occurring. (BZ#1253733)
• If a bonding VLAN interface entered promiscuous mode while it was inactive, the slave interfaces previously did not enter promiscuous mode automatically even after the bonding VLAN interface became active again. With this update, the flag changes are always propagated to interfaces, and slave interfaces thus enter promiscuous mode as expected. (BZ#1253734)

Users of kernel are advised to upgrade to these updated packages. The system must be rebooted for this update to take effect.

Solution

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

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.7 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.7 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for IBM z Systems 6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 6.7 s390x
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.7 ppc64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.7 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.7 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux EUS Compute Node 6.7 x86_64
• Red Hat Enterprise Linux for SAP Solutions for x86_64 - Extended Update Support 6.7 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x

Fixes

CVEs

(none)

References

• http://www.redhat.com/security/updates/classification/#normal