From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-cve-announce@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@kernel.org>
Subject: CVE-2026-43409: kprobes: avoid crash when rmmod/insmod after ftrace killed
Date: Fri, 8 May 2026 16:22:18 +0200 [thread overview]
Message-ID: <2026050843-CVE-2026-43409-509d@gregkh> (raw)
From: Greg Kroah-Hartman <gregkh@kernel.org>
Description
===========
In the Linux kernel, the following vulnerability has been resolved:
kprobes: avoid crash when rmmod/insmod after ftrace killed
After we hit ftrace is killed by some errors, the kernel crash if
we remove modules in which kprobe probes.
BUG: unable to handle page fault for address: fffffbfff805000d
PGD 817fcc067 P4D 817fcc067 PUD 817fc8067 PMD 101555067 PTE 0
Oops: Oops: 0000 [#1] SMP KASAN PTI
CPU: 4 UID: 0 PID: 2012 Comm: rmmod Tainted: G W OE
Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
RIP: 0010:kprobes_module_callback+0x89/0x790
RSP: 0018:ffff88812e157d30 EFLAGS: 00010a02
RAX: 1ffffffff805000d RBX: dffffc0000000000 RCX: ffffffff86a8de90
RDX: ffffed1025c2af9b RSI: 0000000000000008 RDI: ffffffffc0280068
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1025c2af9a
R10: ffff88812e157cd7 R11: 205d323130325420 R12: 0000000000000002
R13: ffffffffc0290488 R14: 0000000000000002 R15: ffffffffc0280040
FS: 00007fbc450dd740(0000) GS:ffff888420331000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffbfff805000d CR3: 000000010f624000 CR4: 00000000000006f0
Call Trace:
<TASK>
notifier_call_chain+0xc6/0x280
blocking_notifier_call_chain+0x60/0x90
__do_sys_delete_module.constprop.0+0x32a/0x4e0
do_syscall_64+0x5d/0xfa0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
This is because the kprobe on ftrace does not correctly handles
the kprobe_ftrace_disabled flag set by ftrace_kill().
To prevent this error, check kprobe_ftrace_disabled in
__disarm_kprobe_ftrace() and skip all ftrace related operations.
The Linux kernel CVE team has assigned CVE-2026-43409 to this issue.
Affected and fixed versions
===========================
Issue introduced in 3.7 with commit ae6aa16fdc163afe6b04b6c073ad4ddd4663c03b and fixed in 6.6.130 with commit 8b6767e4141b2a42745b544d4555cf1614ba1a2d
Issue introduced in 3.7 with commit ae6aa16fdc163afe6b04b6c073ad4ddd4663c03b and fixed in 6.12.78 with commit b0ca81616a010807e91fc31db9be242b96326adc
Issue introduced in 3.7 with commit ae6aa16fdc163afe6b04b6c073ad4ddd4663c03b and fixed in 6.18.19 with commit cae928e3178c75602c21d67e21255d73e7e9ed4f
Issue introduced in 3.7 with commit ae6aa16fdc163afe6b04b6c073ad4ddd4663c03b and fixed in 6.19.9 with commit 9edc79d664832a842012ad105b1521c1a3c35ab3
Issue introduced in 3.7 with commit ae6aa16fdc163afe6b04b6c073ad4ddd4663c03b and fixed in 7.0 with commit e113f0b46d19626ec15388bcb91432c9a4fd6261
Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.
Unaffected versions might change over time as fixes are backported to
older supported kernel versions. The official CVE entry at
https://cve.org/CVERecord/?id=CVE-2026-43409
will be updated if fixes are backported, please check that for the most
up to date information about this issue.
Affected files
==============
The file(s) affected by this issue are:
kernel/kprobes.c
Mitigation
==========
The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes. Individual
changes are never tested alone, but rather are part of a larger kernel
release. Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all. If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
https://git.kernel.org/stable/c/8b6767e4141b2a42745b544d4555cf1614ba1a2d
https://git.kernel.org/stable/c/b0ca81616a010807e91fc31db9be242b96326adc
https://git.kernel.org/stable/c/cae928e3178c75602c21d67e21255d73e7e9ed4f
https://git.kernel.org/stable/c/9edc79d664832a842012ad105b1521c1a3c35ab3
https://git.kernel.org/stable/c/e113f0b46d19626ec15388bcb91432c9a4fd6261
reply other threads:[~2026-05-08 14:24 UTC|newest]
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