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Linux 18.104.22.168 was released about 13 hours ago. As can be seen in the ChangeLog, it included a fair number of bugfix patches (23 commits since 22.214.171.124 was released). One of these patches was indeed assigned a CVE ID. In Hugh Dickins' (patch author) own words:
I found that all of 2.4 and 2.6 have been letting mprotect give write permission to a readonly attachment of shared memory, whether or not IPC would give the caller that permission.
Linux 126.96.36.199 has been released. From the ChangeLog:
This fixes http://bugzilla.kernel.org/show_bug.cgi?id=6388
The bug is caused by ip_route_input dereferencing skb->nh.protocol of the dummy skb passed dow from inet_rtm_getroute (Thanks Thomas for seeing it). It only happens if the route requested is for a multicast IP address.
Linux 188.8.131.52 has been released. From the ChangeLog:
AMD K7/K8 CPUs only save/restore the FOP/FIP/FDP x87 registers in FXSAVE when an exception is pending. This means the value leak through context switches and allow processes to observe some x87 instruction state of other processes.
fix infinite loop in the SCTP-netfilter code: check SCTP chunk size to
guarantee progress of for_each_sctp_chunk(). (all other uses of
for_each_sctp_chunk() are preceded by do_basic_checks(), so this fix
should be complete.)
It is insane to be giving lease_init() the task of freeing the lock it is
supposed to initialise, given that the lock is not guaranteed to be
allocated on the stack. This causes lockups in fcntl_setlease().
The ChangeLog shows three CVE issues (among other things) are addressed:
SCTP: Validate the parameter length in HB-ACK chunk
If SCTP receives a badly formatted HB-ACK chunk, it is possible
that we may access invalid memory and potentially have a buffer
overflow. We should really make sure that the chunk format is
what we expect, before attempting to touch the data.
SCTP: Respect the real chunk length when walking parameters
When performing bound checks during the parameter processing, we
want to use the real chunk and paramter lengths for bounds instead
of the rounded ones. This prevents us from potentially walking of
the end if the chunk length was miscalculated. We still use rounded
lengths when advancing the pointer. This was found during a
conformance test that changed the chunk length without modifying
Netfilter: do_add_counters race, possible oops or info leak
Solar Designer found a race condition in do_add_counters(). The beginning
of paddc is supposed to be the same as tmp which was sanity-checked
above, but it might not be the same in reality. In case the integer
overflow and/or the race condition are triggered, paddc->num_counters
might not match the allocation size for paddc. If the check below
(t->private->number != paddc->num_counters) nevertheless passes (perhaps
this requires the race condition to be triggered), IPT_ENTRY_ITERATE()
would read kernel memory beyond the allocation size, potentially causing
an oops or leaking sensitive data (e.g., passwords from host system or
from another VPS) via counter increments. This requires CAP_NET_ADMIN.
The ChangeLog shows it consists of a single patch for a Netfilter SNMP NAT issue:
Fix memory corruption caused by snmp_trap_decode:
- When snmp_trap_decode fails before the id and address are allocated,
the pointers contain random memory, but are freed by the caller
- When snmp_trap_decode fails after allocating just the ID, it tries
to free both address and ID, but the address pointer still contains
random memory. The caller frees both ID and random memory again.
- When snmp_trap_decode fails after allocating both, it frees both,
and the callers frees both again.
The corruption can be triggered remotely when the ip_nat_snmp_basic
module is loaded and traffic on port 161 or 162 is NATed.