CVE-2025-21914

In the Linux kernel, the following vulnerability has been resolved:

slimbus: messaging: Free transaction ID in delayed interrupt scenario

In case of interrupt delay for any reason, slim_do_transfer() returns timeout error but the transaction ID (TID) is not freed. This results into invalid memory access inside qcom_slim_ngd_rx_msgq_cb() due to invalid TID.

Fix the issue by freeing the TID in slim_do_transfer() before returning timeout error to avoid invalid memory access.

Call trace: __memcpy_fromio+0x20/0x190 qcom_slim_ngd_rx_msgq_cb+0x130/0x290 [slim_qcom_ngd_ctrl] vchan_complete+0x2a0/0x4a0 tasklet_action_common+0x274/0x700 tasklet_action+0x28/0x3c _stext+0x188/0x620 run_ksoftirqd+0x34/0x74 smpboot_thread_fn+0x1d8/0x464 kthread+0x178/0x238 ret_from_fork+0x10/0x20 Code: aa0003e8 91000429 f100044a 3940002b (3800150b) ---[ end trace 0fe00bec2b975c99 ]--- Kernel panic - not syncing: Oops: Fatal exception in interrupt.

This vulnerability poses no security risk to Red Hat Enterprise Linux environments because the SLIMbus audio bus subsystem is not enabled or supported in Red Hat kernels. The flaw involves invalid memory access resulting from unhandled transaction IDs during delayed hardware interrupts on specialized embedded hardware platforms. Consequently, standard Red Hat enterprise installations lack the affected code and cannot be impacted by this flaw.