Linux: >> Linux Kernel >> 6.1.0 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
smack: tcp: ipv4, fix incorrect labeling
Currently, Smack mirrors the label of incoming tcp/ipv4 connections:
when a label 'foo' connects to a label 'bar' with tcp/ipv4,
'foo' always gets 'foo' in returned ipv4 packets. So,
1) returned packets are incorrectly labeled ('foo' instead of 'bar')
2) 'bar' can write to 'foo' without being authorized to write.
Here is a scenario how to see this:
* Take two machines, let's call them C and S,
with active Smack in the default state
(no settings, no rules, no labeled hosts, only builtin labels)
* At S, add Smack rule 'foo bar w'
(labels 'foo' and 'bar' are instantiated at S at this moment)
* At S, at label 'bar', launch a program
that listens for incoming tcp/ipv4 connections
* From C, at label 'foo', connect to the listener at S.
(label 'foo' is instantiated at C at this moment)
Connection succeedes and works.
* Send some data in both directions.
* Collect network traffic of this connection.
All packets in both directions are labeled with the CIPSO
of the label 'foo'. Hence, label 'bar' writes to 'foo' without
being authorized, and even without ever being known at C.
If anybody cares: exactly the same happens with DCCP.
This behavior 1st manifested in release 2.6.29.4 (see Fixes below)
and it looks unintentional. At least, no explanation was provided.
I changed returned packes label into the 'bar',
to bring it into line with the Smack documentation claims.
CVSS Score
8.8
EPSS Score
0.004
Published
2024-10-09
In the Linux kernel, the following vulnerability has been resolved:
fsnotify: clear PARENT_WATCHED flags lazily
In some setups directories can have many (usually negative) dentries.
Hence __fsnotify_update_child_dentry_flags() function can take a
significant amount of time. Since the bulk of this function happens
under inode->i_lock this causes a significant contention on the lock
when we remove the watch from the directory as the
__fsnotify_update_child_dentry_flags() call from fsnotify_recalc_mask()
races with __fsnotify_update_child_dentry_flags() calls from
__fsnotify_parent() happening on children. This can lead upto softlockup
reports reported by users.
Fix the problem by calling fsnotify_update_children_dentry_flags() to
set PARENT_WATCHED flags only when parent starts watching children.
When parent stops watching children, clear false positive PARENT_WATCHED
flags lazily in __fsnotify_parent() for each accessed child.
CVSS Score
4.7
EPSS Score
0.0
Published
2024-10-09
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: Acquire kvm->srcu when handling KVM_SET_VCPU_EVENTS
Grab kvm->srcu when processing KVM_SET_VCPU_EVENTS, as KVM will forcibly
leave nested VMX/SVM if SMM mode is being toggled, and leaving nested VMX
reads guest memory.
Note, kvm_vcpu_ioctl_x86_set_vcpu_events() can also be called from KVM_RUN
via sync_regs(), which already holds SRCU. I.e. trying to precisely use
kvm_vcpu_srcu_read_lock() around the problematic SMM code would cause
problems. Acquiring SRCU isn't all that expensive, so for simplicity,
grab it unconditionally for KVM_SET_VCPU_EVENTS.
=============================
WARNING: suspicious RCU usage
6.10.0-rc7-332d2c1d713e-next-vm #552 Not tainted
-----------------------------
include/linux/kvm_host.h:1027 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
1 lock held by repro/1071:
#0: ffff88811e424430 (&vcpu->mutex){+.+.}-{3:3}, at: kvm_vcpu_ioctl+0x7d/0x970 [kvm]
stack backtrace:
CPU: 15 PID: 1071 Comm: repro Not tainted 6.10.0-rc7-332d2c1d713e-next-vm #552
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Call Trace:
<TASK>
dump_stack_lvl+0x7f/0x90
lockdep_rcu_suspicious+0x13f/0x1a0
kvm_vcpu_gfn_to_memslot+0x168/0x190 [kvm]
kvm_vcpu_read_guest+0x3e/0x90 [kvm]
nested_vmx_load_msr+0x6b/0x1d0 [kvm_intel]
load_vmcs12_host_state+0x432/0xb40 [kvm_intel]
vmx_leave_nested+0x30/0x40 [kvm_intel]
kvm_vcpu_ioctl_x86_set_vcpu_events+0x15d/0x2b0 [kvm]
kvm_arch_vcpu_ioctl+0x1107/0x1750 [kvm]
? mark_held_locks+0x49/0x70
? kvm_vcpu_ioctl+0x7d/0x970 [kvm]
? kvm_vcpu_ioctl+0x497/0x970 [kvm]
kvm_vcpu_ioctl+0x497/0x970 [kvm]
? lock_acquire+0xba/0x2d0
? find_held_lock+0x2b/0x80
? do_user_addr_fault+0x40c/0x6f0
? lock_release+0xb7/0x270
__x64_sys_ioctl+0x82/0xb0
do_syscall_64+0x6c/0x170
entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7ff11eb1b539
</TASK>
CVSS Score
7.8
EPSS Score
0.0
Published
2024-09-27
In the Linux kernel, the following vulnerability has been resolved:
drm/bridge: tc358767: Check if fully initialized before signalling HPD event via IRQ
Make sure the connector is fully initialized before signalling any
HPD events via drm_kms_helper_hotplug_event(), otherwise this may
lead to NULL pointer dereference.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-09-27
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Skip inactive planes within ModeSupportAndSystemConfiguration
[Why]
Coverity reports Memory - illegal accesses.
[How]
Skip inactive planes.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-09-27
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check link_index before accessing dc->links[]
[WHY & HOW]
dc->links[] has max size of MAX_LINKS and NULL is return when trying to
access with out-of-bound index.
This fixes 3 OVERRUN and 1 RESOURCE_LEAK issues reported by Coverity.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-09-27
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check msg_id before processing transcation
[WHY & HOW]
HDCP_MESSAGE_ID_INVALID (-1) is not a valid msg_id nor is it a valid
array index, and it needs checking before used.
This fixes 4 OVERRUN issues reported by Coverity.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-09-27
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check num_valid_sets before accessing reader_wm_sets[]
[WHY & HOW]
num_valid_sets needs to be checked to avoid a negative index when
accessing reader_wm_sets[num_valid_sets - 1].
This fixes an OVERRUN issue reported by Coverity.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-09-27
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Stop amdgpu_dm initialize when stream nums greater than 6
[Why]
Coverity reports OVERRUN warning. Should abort amdgpu_dm
initialize.
[How]
Return failure to amdgpu_dm_init.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-09-27
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check gpio_id before used as array index
[WHY & HOW]
GPIO_ID_UNKNOWN (-1) is not a valid value for array index and therefore
should be checked in advance.
This fixes 5 OVERRUN issues reported by Coverity.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-09-27