Bug 2388927 (CVE-2025-38538) - CVE-2025-38538 kernel: dmaengine: nbpfaxi: Fix memory corruption in probe()
Summary: CVE-2025-38538 kernel: dmaengine: nbpfaxi: Fix memory corruption in probe()
Keywords:
Status: NEW
Alias: CVE-2025-38538
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2025-08-16 12:01 UTC by OSIDB Bzimport
Modified: 2025-08-18 13:10 UTC (History)
0 users

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:


Attachments (Terms of Use)

Description OSIDB Bzimport 2025-08-16 12:01:50 UTC
In the Linux kernel, the following vulnerability has been resolved:

dmaengine: nbpfaxi: Fix memory corruption in probe()

The nbpf->chan[] array is allocated earlier in the nbpf_probe() function
and it has "num_channels" elements.  These three loops iterate one
element farther than they should and corrupt memory.

The changes to the second loop are more involved.  In this case, we're
copying data from the irqbuf[] array into the nbpf->chan[] array.  If
the data in irqbuf[i] is the error IRQ then we skip it, so the iterators
are not in sync.  I added a check to ensure that we don't go beyond the
end of the irqbuf[] array.  I'm pretty sure this can't happen, but it
seemed harmless to add a check.

On the other hand, after the loop has ended there is a check to ensure
that the "chan" iterator is where we expect it to be.  In the original
code we went one element beyond the end of the array so the iterator
wasn't in the correct place and it would always return -EINVAL.  However,
now it will always be in the correct place.  I deleted the check since
we know the result.


Note You need to log in before you can comment on or make changes to this bug.