CVE-2026-99244
In the Linux kernel, the following vulnerability has been resolved: pid_namespace: prevent TIF_NOTIFY_SIGNAL from interrupting the reaper Since commit 7fea700e…
Impact
In the Linux kernel, the following vulnerability has been resolved: pid_namespace: prevent TIF_NOTIFY_SIGNAL from interrupting the reaper Since commit 7fea700e04bd ("zap_pid_ns_processes: clear TIF_NOTIFY_SIGNAL along with TIF_SIGPENDING") zap_pid_ns_processes() clears TIF_NOTIFY_SIGNAL before every kernel_wait4() call. Otherwise kernel_wait4() doesn't sleep and returns -ERESTARTSYS if signal_pending() is true and the reaper busy-waits. But clearing TIF_NOTIFY_SIGNAL doesn't fix it. It can get raised again. For example, klp_send_signals() sets it raw against any task that hasn't transitioned yet. And it keeps sending it until the livepatch finishes. The sleep loop waiting for pid_allocated to drop has the same problem and it doesn't even clear anything. So a schedule() in TASK_INTERRUPTIBLE returns immediately. Use a no_notify_signal guard. signal_pending() will ignore TIF_NOTIFY_SIGNAL and the pid namespace reaper sleeps until a child exits or free_pid() wakes it.
Affected products · Linux
| Product | Affected versions |
|---|---|
| Linux | from edd2754a62bee8d97b4808a15de024f66a1ddccf before 2c20ace1698d03a23467351be1d281e89b36ade3 from 3466abafa9f4f81a869da828e52a12f693175ec2 before 9ab0324f4868eeb20c63f063a1e5bc01d5539212 from 7fea700e04bd3f424c2d836e98425782f97b494e before 30b274508c743f243c82904954c4e416d7143d4c from 7fea700e04bd3f424c2d836e98425782f97b494e before 70178691c467c8f9f722765299fd8524c3121a35 from 7fea700e04bd3f424c2d836e98425782f97b494e before 3d15ac36ce174477efa5365e424dbd47950fd2b9 from 7fea700e04bd3f424c2d836e98425782f97b494e before f46cd8241d9b83f2279cc0db3e9d3e181b548a59 |
References
- NVD record
- CVE.org record
- GitHub advisory
- https://git.kernel.org/stable/c/2c20ace1698d03a23467351be1d281e89b36ade3
- https://git.kernel.org/stable/c/9ab0324f4868eeb20c63f063a1e5bc01d5539212
- https://git.kernel.org/stable/c/30b274508c743f243c82904954c4e416d7143d4c
- https://git.kernel.org/stable/c/70178691c467c8f9f722765299fd8524c3121a35
- https://git.kernel.org/stable/c/3d15ac36ce174477efa5365e424dbd47950fd2b9
- https://git.kernel.org/stable/c/f46cd8241d9b83f2279cc0db3e9d3e181b548a59
- https://github.com/advisories/GHSA-7cwf-57xm-qrxg
- https://nvd.nist.gov/vuln/detail/CVE-2026-99244
- https://git.kernel.org/stable/c/5c0985dd3c32fc2bbd0e8beaf13cf52cd97376a2