Bug 2383907 (CVE-2025-38483)

Summary: CVE-2025-38483 kernel: comedi: das16m1: Fix bit shift out of bounds
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Version: unspecifiedKeywords: Security
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OS: Linux   
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Description OSIDB Bzimport 2025-07-28 12:02:24 UTC
In the Linux kernel, the following vulnerability has been resolved:

comedi: das16m1: Fix bit shift out of bounds

When checking for a supported IRQ number, the following test is used:

	/* only irqs 2, 3, 4, 5, 6, 7, 10, 11, 12, 14, and 15 are valid */
	if ((1 << it->options[1]) & 0xdcfc) {

However, `it->options[i]` is an unchecked `int` value from userspace, so
the shift amount could be negative or out of bounds.  Fix the test by
requiring `it->options[1]` to be within bounds before proceeding with
the original test.

Comment 1 Avinash Hanwate 2025-07-28 15:23:42 UTC
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025072815-CVE-2025-38483-ab88@gregkh/T