Linux Kernel up to 6.1.110/6.6.51/6.10.10 mlx5 null pointer dereference

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.1.110/6.6.51/6.10.10. This affects an unknown part of the component mlx5. The manipulation leads to null pointer dereference. This vulnerability is listed as CVE-2024-46857. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.110/6.6.51/6.10.10 and classified as critical. This issue affects some unknown processing of the component mlx5. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix bridge mode operations when there are no VFs Currently, trying to set the bridge mode attribute when numvfs=0 leads to a crash: bridge link set dev eth2 hwmode vepa [ 168.967392] BUG: kernel NULL pointer dereference, address: 0000000000000030 [...] [ 168.969989] RIP: 0010:mlx5_add_flow_rules+0x1f/0x300 [mlx5_core] [...] [ 168.976037] Call Trace: [ 168.976188] [ 168.978620] _mlx5_eswitch_set_vepa_locked+0x113/0x230 [mlx5_core] [ 168.979074] mlx5_eswitch_set_vepa+0x7f/0xa0 [mlx5_core] [ 168.979471] rtnl_bridge_setlink+0xe9/0x1f0 [ 168.979714] rtnetlink_rcv_msg+0x159/0x400 [ 168.980451] netlink_rcv_skb+0x54/0x100 [ 168.980675] netlink_unicast+0x241/0x360 [ 168.980918] netlink_sendmsg+0x1f6/0x430 [ 168.981162] ____sys_sendmsg+0x3bb/0x3f0 [ 168.982155] ___sys_sendmsg+0x88/0xd0 [ 168.985036] __sys_sendmsg+0x59/0xa0 [ 168.985477] do_syscall_64+0x79/0x150 [ 168.987273] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 168.987773] RIP: 0033:0x7f8f7950f917 (esw->fdb_table.legacy.vepa_fdb is null) The bridge mode is only relevant when there are multiple functions per port. Therefore, prevent setting and getting this setting when there are no VFs. Note that after this change, there are no settings to change on the PF interface using `bridge link` when there are no VFs, so the interface no longer appears in the `bridge link` output.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2024-46857 since 09/11/2024. The exploitation is known to be difficult. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 208099 (Debian dsa-5782 : affs-modules-6.1.0-21-4kc-malta-di - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.111, 6.6.52 or 6.10.11 eliminates this vulnerability. Applying the patch 52c4beb79e09/65feee671e37/505ae01f75f8/b1d305abef46 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (208099) and CERT Bund (WID-SEC-2024-3050). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Google Container-Optimized OS
• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• Kyocera Printer
• RESF Rocky Linux
• Broadcom Brocade SANnav
• Open Source Linux Kernel
• IBM QRadar SIEM
• SolarWinds Security Event Manager

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.110
• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.6.24
• 6.6.25
• 6.6.26
• 6.6.27
• 6.6.28
• 6.6.29
• 6.6.30
• 6.6.31
• 6.6.32
• 6.6.33
• 6.6.34
• 6.6.35
• 6.6.36
• 6.6.37
• 6.6.38
• 6.6.39
• 6.6.40
• 6.6.41
• 6.6.42
• 6.6.43
• 6.6.44
• 6.6.45
• 6.6.46
• 6.6.47
• 6.6.48
• 6.6.49
• 6.6.50
• 6.6.51
• 6.10.0
• 6.10.1
• 6.10.2
• 6.10.3
• 6.10.4
• 6.10.5
• 6.10.6
• 6.10.7
• 6.10.8
• 6.10.9
• 6.10.10

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

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Exploitinginfo

Threat Intelligenceinfo

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Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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