In the Linux kernel, the following vulnerability has been resolved:
misc: ibmasm: fix OOB MMIO read in ibmasm_handle_mouse_interrupt()
ibmasm_handle_mouse_interrupt() performs an out-of-bounds MMIO read
when the queue reader or writer index from hardware exceeds
REMOTE_QUEUE_SIZE (60).
A compromised service processor can trigger this by writing an
out-of-range value to the reader or writer MMIO register before
asserting an interrupt. Since writer is re-read from hardware on
every loop iteration, it can also be set to an out-of-range value
after the loop has already started.
The root cause is that get_queue_reader() and get_queue_writer() return
raw readl() values that are passed directly into get_queue_entry(),
which computes:
queue_begin + reader * sizeof(struct remote_input)
with no bounds check. This unchecked MMIO address is then passed to
memcpy_fromio(), reading 8 bytes from unintended device registers.
For sufficiently large values the address falls outside the PCI BAR
mapping entirely, triggering a machine check exception.
Fix by checking both indices against REMOTE_QUEUE_SIZE at the top of
the loop body, before any call to get_queue_entry(). On an out-of-range
value, reset the reader register to 0 via set_queue_reader() before
breaking, so that normal queue operation can resume if the corrupted
hardware state is transient.
References
Configurations
Configuration 1 (hide)
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History
No history.
Information
Published : 2026-05-27 14:17
Updated : 2026-06-17 10:52
NVD link : CVE-2026-46022
Mitre link : CVE-2026-46022
CVE.ORG link : CVE-2026-46022
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-125
Out-of-bounds Read