CVE-2026-53158: In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Fix NULL pointer dereference in rpmsg callback A NULL pointer der...

Description

In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Fix NULL pointer dereference in rpmsg callback A NULL pointer dereference was observed on Hawi at boot when the DSP sends a glink message before fastrpc_rpmsg_probe() has completed initialization: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000178 pc : _raw_spin_lock_irqsave+0x34/0x8c lr : fastrpc_rpmsg_callback+0x3c/0xcc [fastrpc] ... Call trace: _raw_spin_lock_irqsave+0x34/0x8c (P) fastrpc_rpmsg_callback+0x3c/0xcc [fastrpc] qcom_glink_native_rx+0x538/0x6a4 qcom_glink_smem_intr+0x14/0x24 [qcom_glink_smem] The faulting address 0x178 corresponds to the lock variable inside struct fastrpc_channel_ctx, confirming that cctx is NULL when fastrpc_rpmsg_callback() attempts to take the spinlock. There are two issues here. First, dev_set_drvdata() is called before spin_lock_init() and idr_init(), leaving a window where the callback can retrieve a valid cctx pointer but operate on an uninitialized spinlock. Second, the rpmsg channel becomes live as soon as the driver is bound, so fastrpc_rpmsg_callback() can fire before dev_set_drvdata() is called at all, resulting in dev_get_drvdata() returning NULL. Fix both issues by moving all cctx initialization ahead of dev_set_drvdata() so the structure is fully initialized before it becomes visible to the callback, and add a NULL check in fastrpc_rpmsg_callback() as a guard against any remaining window.

Metrics

EPSS Probability

0.17%

6.4th percentile

Probability of exploitation in the next 30 days. Learn more

References

Timeline

Published: Jun 25, 2026
Last Modified: Jun 25, 2026
Status: Received

Frequently Asked Questions

What is CVE-2026-53158?

In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Fix NULL pointer dereference in rpmsg callback A NULL pointer dereference was observed on Hawi at boot when the DSP sends a glink message before fastrpc_rpmsg_probe() has completed initialization: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000178 pc : _raw_spin_lock_irqsave+0x34/0x8c lr : fastrpc_rpmsg_callback+0x3c/0xcc [fastrpc] ... Call trace: _raw_spin_lock_irqsave+0x34/0x8c (P) fastrpc_rpmsg_callback+0x3c/0xcc [fastrpc] qcom_glink_native_rx+0x538/0x6a4 qcom_glink_smem_intr+0x14/0x24 [qcom_glink_smem] The faulting address 0x178 corresponds to the lock variable inside struct fastrpc_channel_ctx, confirming that cctx is NULL when fastrpc_rpmsg_callback() attempts to take the spinlock. There are two issues here. First, dev_set_drvdata() is called before spin_lock_init() and idr_init(), leaving a window where the callback can retrieve a valid cctx pointer but operate on an uninitialized spinlock. Second, the rpmsg channel becomes live as soon as the driver is bound, so fastrpc_rpmsg_callback() can fire before dev_set_drvdata() is called at all, resulting in dev_get_drvdata() returning NULL. Fix both issues by moving all cctx initialization ahead of dev_set_drvdata() so the structure is fully initialized before it becomes visible to the callback, and add a NULL check in fastrpc_rpmsg_callback() as a guard against any remaining window.

How severe is CVE-2026-53158?

Severity scoring for CVE-2026-53158 is pending analysis. The EPSS model estimates a 0.17% probability of exploitation in the next 30 days.

How do I fix CVE-2026-53158?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.