CVE-2021-47528

published 2024-05-24

CVE-2021-47528: In the Linux kernel, the following vulnerability has been resolved: usb: cdnsp: Fix a NULL pointer dereference in cdnsp_endpoint_init() In…

Priority P4 19 medium 5.5 CVSS 3.1

AV L AC L PR L UI N S U C N I N A H

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

usb: cdnsp: Fix a NULL pointer dereference in cdnsp_endpoint_init()

In cdnsp_endpoint_init(), cdnsp_ring_alloc() is assigned to pep->ring
and there is a dereference of it in cdnsp_endpoint_init(), which could
lead to a NULL pointer dereference on failure of cdnsp_ring_alloc().

Fix this bug by adding a check of pep->ring.

This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.

Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.

Builds with CONFIG_USB_CDNSP_GADGET=y show no new warnings,
and our static analyzer no longer warns about this code.

Affected

8 ranges

Vendor	Product	Version range	Fixed in
debian	linux	< linux 5.15.15-1 (bookworm)	linux 5.15.15-1 (bookworm)
linux	linux	—	—
linux	linux	>= 3d82904559f4f5a2622db1b21de3edf2eded7664 < 7d94bc8e335cb33918e52efdbe192c36707bfa24	7d94bc8e335cb33918e52efdbe192c36707bfa24
linux	linux	>= 3d82904559f4f5a2622db1b21de3edf2eded7664 < 37307f7020ab38dde0892a578249bf63d00bca64	37307f7020ab38dde0892a578249bf63d00bca64
linux	linux_kernel	>= 0 < 5.15.15-1	5.15.15-1
linux	linux_kernel	>= 0 < 5.15.15-1	5.15.15-1
linux	linux_kernel	>= 0 < 5.15.15-1	5.15.15-1
linux	linux_kernel	>= 5.12 < 5.15.7	5.15.7

CVSS provenance

nvd v3.1 5.5 MEDIUM CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

osv 5.5 MEDIUM

vendor_debian 5.5 MEDIUM

vendor_redhat 5.5 MEDIUM

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CWE-476