CVE-2026-98903 mailbox: imx: Add a channel shutdown field
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-98903?
CVE-2026-98903 is a vulnerability in Linux, published on 23 Oct 2026.
Official description
In the Linux kernel, the following vulnerability has been resolved:
mailbox: imx: Add a channel shutdown field
sashiko complained about possible teardown problem. The scenario
CPU 0 CPU 1 imx_mu_isr() imx_mu_shutdown() imx_mu_xcr_rmw(priv, IMX_MU_RCR, 0, IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx)); imx_mu_specific_rx() imx_mu_xcr_rmw(priv, IMX_MU_RCR, IMX_MU_xCR_RIEn(priv->dcfg->type, 0), 0); free_irq()
The RX event remains enabled because in this short window the RX event was disabled in ->shutdown() while the interrupt was active and then enabled again by the ISR while ->shutdown waited in free_irq().
This race requires timing and if happens can be problematic on shared handlers if the "removed" channel triggers an interrupt. In this case the irq-core will shutdown the interrupt with the "nobody cared" message.
Introduce imx_mu_con_priv::shutdown to signal that the channel is shutting down. This flag is set with the lock held (by imx_mu_xcr_clr_shut()). The unmask side uses imx_mu_xcr_set_act() which only enables the event if the channel has not been shutdown and serialises on the same lock.
Which versions are affected by CVE-2026-98903?
How do I fix CVE-2026-98903?
Upgrade to a fixed version.
Is CVE-2026-98903 being exploited?
There is no known exploitation of CVE-2026-98903 in the wild and no public exploit code.
Sources
Also known as AZL-110576, BELL-CVE-2026-98903, DEBIAN-CVE-2026-98903, GHSA-6pc9-8xrq-jmj4, UBUNTU-CVE-2026-98903.