Affected: Alpaquita:23: linux-lts, Alpaquita:25: linux-lts, Alpaquita:stream: linux-lts

In the Linux kernel, the following vulnerability has been resolved:

net: drop_monitor: fix info leak in NET_DM_ATTR_PAYLOAD

net_dm_packet_report_fill() and net_dm_hw_packet_report_fill() open code the NET_DM_ATTR_PAYLOAD attribute to avoid zeroing the packet payload before overwriting it with skb_copy_bits().

skb_put() reserves nla_total_size(payload_len), i.e. the header plus the NLA_ALIGN() padding, but only payload_len bytes are copied in. When payload_len is not a multiple of 4 the 1-3 padding bytes are never initialized and are leaked to user space inside the netlink message.

KMSAN confirms the leak for the software path when the packet payload length is not 4-byte aligned:

BUG: KMSAN: kernel-infoleak in _copy_to_iter _copy_to_iter __skb_datagram_iter skb_copy_datagram_iter netlink_recvmsg sock_recvmsg __sys_recvfrom Uninit was created at: kmem_cache_alloc_node_noprof __alloc_skb net_dm_packet_work Bytes 173-175 of 176 are uninitialized

Use __nla_reserve(), which sets up the attribute header and zeroes the padding, instead of open coding the attribute construction.

In the Linux kernel, the following vulnerability has been resolved:

net: drop_monitor: fix info leak in NET_DM_ATTR_PAYLOAD

net_dm_packet_report_fill() and net_dm_hw_packet_report_fill() open code the NET_DM_ATTR_PAYLOAD attribute to avoid zeroing the packet payload before overwriting it with skb_copy_bits().

skb_put() reserves nla_total_size(payload_len), i.e. the header plus the NLA_ALIGN() padding, but only payload_len bytes are copied in. When payload_len is not a multiple of 4 the 1-3 padding bytes are never initialized and are leaked to user space inside the netlink message.

KMSAN confirms the leak for the software path when the packet payload length is not 4-byte aligned:

BUG: KMSAN: kernel-infoleak in _copy_to_iter _copy_to_iter __skb_datagram_iter skb_copy_datagram_iter netlink_recvmsg sock_recvmsg __sys_recvfrom Uninit was created at: kmem_cache_alloc_node_noprof __alloc_skb net_dm_packet_work Bytes 173-175 of 176 are uninitialized

Use __nla_reserve(), which sets up the attribute header and zeroes the padding, instead of open coding the attribute construction.

Security update for the Linux Kernel

Security update for the Linux Kernel

Affected: Ubuntu:16.04:LTS: linux-hwe-edge, Ubuntu:18.04:LTS: linux-aws-5.0, Ubuntu:18.04:LTS: linux-aws-5.3, Ubuntu:Pro:18.04:LTS: linux-aws-5.4, Ubuntu:18.04:LTS: linux-azure, Ubuntu:18.04:LTS: linux-azure-5.3, Ubuntu:Pro:18.04:LTS: linux-azure-5.4, Ubuntu:18.04:LTS: linux-azure-edge, Ubuntu:18.04:LTS: linux-gcp, Ubuntu:18.04:LTS: linux-gcp-5.3 and 219 more

In the Linux kernel, the following vulnerability has been resolved: net: drop_monitor: fix info leak in NET_DM_ATTR_PAYLOAD net_dm_packet_report_fill() and net_dm_hw_packet_report_fill() open code the NET_DM_ATTR_PAYLOAD attribute to avoid zeroing the packet payload before overwriting it with skb_copy_bits(). skb_put() reserves nla_total_size(payload_len), i.e. the header plus the NLA_ALIGN() padding, but only payload_len bytes are copied in. When payload_len is not a multiple of 4 the 1-3 padding bytes are never initialized and are leaked to user space inside the netlink message. KMSAN confirms the leak for the software path when the packet payload length is not 4-byte aligned: BUG: KMSAN: kernel-infoleak in _copy_to_iter _copy_to_iter __skb_datagram_iter skb_copy_datagram_iter netlink_recvmsg sock_recvmsg __sys_recvfrom Uninit was created at: kmem_cache_alloc_node_noprof __alloc_skb net_dm_packet_work Bytes 173-175 of 176 are uninitialized Use __nla_reserve(), which sets up the attribute header and zeroes the padding, instead of open coding the attribute construction.

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen, darunter möglicherweise die Ausführung von beliebigem Code, die Ausweitung von Berechtigungen, die Offenlegung von Informationen, die Manipulation von Daten oder Denial-of-Service-Zustände.