CVE-2026-68289

What the bug is

In tipc_recvmsg(), the copy length is computed as: copy = min_t(int, dlen - offset, buflen); buflen is size_t but min_t(int, ...) casts it to int. When buflen exceeds INT_MAX (e.g. 0xFFFFFFFF via io_uring provided buffers), it wraps negative, wins the comparison, and the negative copy length propagates to simple_copy_to_iter() where int-to-size_t promotion makes it SIZE_MAX, triggering a WARN_ON. tipc_recvstream() has the same pattern. Kernel panic - not syncing: kernel: panic_on_warn set ... RIP: 0010:simple_copy_to_iter+0x9e/0xd0 (net/core/datagram.c:521) Call Trace: __skb_datagram_iter+0x123/0x8b0 (net/core/datagram.c:402) skb_copy_datagram_iter+0x77/0x1a0 (net/core/datagram.c:534) tipc_recvmsg+0x3d7/0xe80 (net/tipc/socket.c:1934) io_recvmsg+0x47e/0xda0 Fix by changing min_t(int, ...) to min_t(size_t, ...) in both functions. The result is always <= (dlen - offset), which is bounded by TIPC maximum message size (0x1ffff bytes), so the implicit narrowing on assignment to int copy is always safe.

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.

net/tipc/socket.c

What this is

TIPC NETWORK LAYERMAINTAINERS section matched on net/tipc/ · netdev@vger.kernel.org · Maintained

Kernel module

tipc

Check it on the machine

grep -w CONFIG_TIPC /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 tipc

Prints 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, sid, bookworm · linux-6.12m

m

a loadable module on every flavour - check lsmod, can be blacklisted

Build switch

CONFIG_TIPC

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

2026-08-10 (2 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.18%, higher than 7.1% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

net/tipc

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
4.12	6.1.189	9fd4f9267114
4.12	6.6.158	93580911f02d
4.12	6.12.111	1b6066313b9b
4.12	6.18.53	7364014fdc28
4.12	7.1.6	fe9bf32bb18f
4.12	7.2	47f42ff521b4

Debian advisories