CVE-2024-46857: net/mlx5: Fix bridge mode operations when there are no VFs
First published: Fri Sep 27 2024(Updated: )
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] <TASK> [ 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.
Credit: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 416baaa9-dc9f-4396-8d5f-8c081fb06d67
| Affected Software | Affected Version | How to fix |
|---|---|---|
| Linux Kernel | >=5.1<6.1.111 | |
| Linux Kernel | >=6.2<6.6.52 | |
| Linux Kernel | >=6.7<6.10.11 | |
| Linux Kernel | =6.11-rc1 | |
| Linux Kernel | =6.11-rc2 | |
| Linux Kernel | =6.11-rc3 | |
| Linux Kernel | =6.11-rc4 | |
| Linux Kernel | =6.11-rc5 | |
| Linux Kernel | =6.11-rc6 | |
| Linux Kernel | =6.11-rc7 | |
| debian/linux | <=5.10.223-1<=5.10.234-1 | 6.1.129-1 6.1.135-1 6.12.22-1 6.12.25-1 |
| debian/linux-6.1 | 6.1.129-1~deb11u1 |
Never miss a vulnerability like this again
Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.
Reference Links
- https://git.kernel.org/stable/c/505ae01f75f839b54329164bbfecf24cc1361b31
- https://git.kernel.org/stable/c/52c4beb79e095e0631b5cac46ed48a2aefe51985
- https://git.kernel.org/stable/c/65feee671e37f3b6eda0b6af28f204b5bcf7fa50
- https://git.kernel.org/stable/c/b1d305abef4640af1b4f1b4774d513cd81b10cfc
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-46857
- https://nvd.nist.gov/vuln/detail/CVE-2024-46857
- https://launchpad.net/bugs/cve/CVE-2024-46857
- https://security-tracker.debian.org/tracker/CVE-2024-46857
- https://ubuntu.com/security/CVE-2024-46857
- https://git.kernel.org/linus/b1d305abef4640af1b4f1b4774d513cd81b10cfc
Frequently Asked Questions
What is the severity of CVE-2024-46857?
CVE-2024-46857 has been classified as moderately severe due to its potential to crash the system when setting the bridge mode attribute incorrectly.
How do I fix CVE-2024-46857?
To resolve CVE-2024-46857, you should update your Linux kernel to a patched version like 6.1.123-1 or later.
Which versions of the Linux kernel are affected by CVE-2024-46857?
CVE-2024-46857 affects Linux kernel versions from 5.1 up to but not including 6.2, as well as specific release candidates of 6.11.
What is the nature of the vulnerability in CVE-2024-46857?
The vulnerability in CVE-2024-46857 involves a crash that occurs when attempting to change bridge mode settings without any virtual functions present.
How can I verify if I am vulnerable to CVE-2024-46857?
To check for vulnerability to CVE-2024-46857, ensure your Linux kernel version is below 6.2 and verify if your bridge mode settings are being manipulated.
- agent/title
- agent/type
- agent/first-publish-date
- agent/severity
- agent/remedy
- agent/weakness
- agent/references
- collector/mitre-cve
- source/MITRE
- agent/last-modified-date
- agent/trending
- agent/author
- collector/usn-cve
- source/Ubuntu
- agent/description
- agent/event
- agent/source
- collector/nvd-cve
- source/NVD
- agent/software-canonical-lookup
- agent/software-canonical-lookup-request
- collector/nvd-api
- agent/softwarecombine
- agent/tags
- collector/security-tracker-debian
- source/Debian
- vendor/linux
- canonical/linux kernel
- version/linux kernel/5.1
- version/linux kernel/6.2
- version/linux kernel/6.7
- version/linux kernel/6.11-rc1
- version/linux kernel/6.11-rc2
- version/linux kernel/6.11-rc3
- version/linux kernel/6.11-rc4
- version/linux kernel/6.11-rc5
- version/linux kernel/6.11-rc6
- version/linux kernel/6.11-rc7
- package-manager/debian