RHSA-2018:2791

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.

One may change the default 4MB and 3MB values of net.ipv4.ipfrag_high_thresh and net.ipv4.ipfrag_low_thresh (and their ipv6 counterparts net.ipv6.ipfrag_high_thresh and net.ipv6.ipfrag_low_thresh) to 256 kB and 192 kB (respectively) or below. Tests show some to significant CPU saturation drop during an attack, depending on a hardware, configuration and environment. There can be some impact on performance though, due to ipfrag_high_thresh of 262144 bytes, as only two 64K fragments can fit in the reassembly queue at the same time. For example, there is a risk of breaking applications that rely on large UDP packets. See the Mitigation section in the https://access.redhat.com/articles/3553061 article for the script to quickly change to/from default and lower settings.