Look up another CVE · open CVE-2026-98359 in the interactive tracker
CVE-2026-98359
RDMA/core: Reject unregistering netdevs in ib_get_eth_speed
Published 2026-10-06 (13 days ago) by the Linux kernel CNA. Subsystem drivers/infiniband. Debian urgency: not yet assigned.
What to do, per Debian release
Debian's own status for CVE-2026-98359 in every release this site tracks, and what each one means in practice. Every status below is the one the Debian Security Team publishes for this CVE. source
| Release | Status | Version | What this means |
|---|---|---|---|
| Debian 12bookworm | fixedDLA-4841-1 · 2026-10-17 · text | 6.1.190-1 | Update the kernel and reboot. DLA-4841-1 shipped the fix on 2026-10-17, in 6.1.190-1. A running kernel keeps the old code until the machine restarts. |
| Debian 13trixie | fixedDSA-6568-1 · 2026-10-16 · text | 6.12.113-1 | Update the kernel and reboot. DSA-6568-1 shipped the fix on 2026-10-16, in 6.12.113-1. A running kernel keeps the old code until the machine restarts. |
| Debian 14forky | fixed | 7.2.8-1 | Update the kernel and reboot. Fixed in 7.2.8-1. A running kernel keeps the old code until the machine restarts. |
| Debian unstablesid | fixed | 7.2.8-1 | Update the kernel and reboot. Fixed in 7.2.8-1. A running kernel keeps the old code until the machine restarts. |
The vulnerability
What the bug is
ib_device_get_netdev() intentionally returns a referenced net_device even when it is unregistering, so matching and cleanup callers can still find the association. The reference keeps struct net_device allocated, but does not guarantee that the device remains operational. ib_get_eth_speed() uses the returned device operationally by invoking its ethtool callback. Although that call is made under RTNL, the function does not verify the registration state first. An asynchronous RDMA port query can therefore call into a netdev after NETDEV_UNREGISTER and ndo_uninit have completed. Check for NETREG_REGISTERED while holding RTNL and return -ENODEV for a device which is being unregistered. Keeping RTNL across the check and the ethtool operation prevents unregister from starting between them. Keep the speed fallback and warning under RTNL as well, so the warning can safely read netdev->name. Drop the netdev reference before releasing RTNL once all accesses to the device are complete.
Where it lives
The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.
drivers/infiniband/core/verbs.c
- What this is
- INFINIBAND SUBSYSTEMMAINTAINERS section matched on drivers/infiniband/ · linux-rdma@vger.kernel.org · Supported
- Kernel module
- ib_core
Check it on the machine
grep -w CONFIG_INFINIBAND /boot/config-$(uname -r)Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.
lsmod | grep -w ib_corePrints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.
Show whether Debian builds this, per release
Debian builds this as a loadable module. Every release below compiles it as a module on every flavour, so whether the code is in the running kernel depends on whether that module is loaded.
- bookworm, trixie, forky, sidm
- m
- a loadable module on every flavour - check lsmod, can be blacklisted
- Build switch
- CONFIG_INFINIBAND
From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages
Signals
- Published
- 2026-10-06 (13 days ago)source
- CVSS
- 7.0 high
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:Hsource recompute it - Attack vector
- local (AV:L)source
- EPSS
- 0.12%, higher than 1.8% of all CVEssource
- CISA KEV
- not listedthe KEV catalogue
- Debian urgency
- not yet assignedsource
- Subsystem
- drivers/infiniband
Upstream fixes
The versions the CNA records as introducing and fixing this, and the commit for each. source
| Introduced | Fixed in | Commit |
|---|---|---|
| 4.14 | 6.1.189 | be4b44c8b47c |
| 4.14 | 6.6.158 | 45c60ffc7977 |
| 4.14 | 6.12.112 | 520cd057f138 |
| 4.14 | 6.18.54 | a219459fbd1b |
| 4.14 | 7.2.8 | 5bd42f74ec3b |
| 4.14 | 7.3 | ef9fbe1b93f3 |
Debian advisories
| Advisory | Date | Shipped to | Debian |
|---|---|---|---|
| DLA-4841-1 | 2026-10-17 | bookworm 6.1.190-1 | tracker |
| DSA-6568-1 | 2026-10-16 | trixie 6.12.113-1 | tracker |
Why the CNA scored it this way
Quoted from the kernel CNA's own scoring file, word for word. A highlighted metric carries the most severe value CVSS v3.1 defines for it, which is what pushes the score up. source
- AV:LAttack vector, local
- ib_get_eth_speed() is reached via ib_query_port() -> driver query_port (rxe_query_port, siw_query_port, irdma, bnxt_re, hns, mana, erdma...) from local uverbs QUERY_PORT ioctls on /dev/infiniband/uverbs*, RDMA_NLDEV_CMD_PORT_GET netlink or the ib cache work; no remote peer supplies data to this path.
- AC:HAttack complexity, high
- The faulty call needs the port's bound netdev to be between NETDEV_UNREGISTER/ndo_uninit and the queued ib_unregister_device_queued() teardown. The querying user can hammer query_port, but unregistering that netdev is an admin or driver action they cannot arrange on demand.
- PR:LPrivileges required, low
- The query side needs no capability: RDMA_NLDEV_CMD_PORT_GET has no RDMA_NL_ADMIN_PERM flag, and uverbs query_port only needs an open uverbs device. Binding rxe/siw via RDMA_NLDEV_CMD_NEWLINK needs init-ns CAP_NET_ADMIN, so the attacker relies on an existing RoCE/iWARP port.
- UI:NUser interaction, none
- No victim action is needed. The attacker only issues port queries, and the unregister event is a system state change (counted under AC:H), not a user being tricked into doing something.
- S:UScope, unchanged
- The bug and its impact are both in the host kernel. No VM, IOMMU or sandbox boundary is crossed.
- C:HConfidentiality impact, high
- __ethtool_get_link_ksettings() runs on a netdev whose ndo_uninit has already run. For example, ipvlan_ethtool_get_link_ksettings() dereferences ipvlan->phy_dev after ipvlan_port_put() dropped the port's phy_dev reference, which lets freed net_device memory be read.
- I:HIntegrity impact, high
- The stale or freed lower net_device is used to load and call ethtool_ops->get_link_ksettings through a function pointer. A use-after-free that reaches an indirect call can be groomed toward control-flow hijack.
- A:HAvailability impact, high
- syzbot hit this as a kernel crash. Calling ethtool callbacks on a torn-down device (freed pcpu/port state in macvlan/ipvlan/team uninit) oopses the kernel.