CVE-2021-47559

net/smc: Fix NULL pointer dereferencing in smc_vlan_by_tcpsk()

MEDIUM
5.5
CVSS Score
Published: May 24, 2024 at 03:12 PM UTC
Updated: August 5, 2026 at 09:24 AM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
MEDIUM5.5
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

Description

In the Linux kernel, the following vulnerability has been resolved: net/smc: Fix NULL pointer dereferencing in smc_vlan_by_tcpsk() Coverity reports a possible NULL dereferencing problem: in smc_vlan_by_tcpsk(): 6. returned_null: netdev_lower_get_next returns NULL (checked 29 out of 30 times). 7. var_assigned: Assigning: ndev = NULL return value from netdev_lower_get_next. 1623 ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower); CID 1468509 (#1 of 1): Dereference null return value (NULL_RETURNS) 8. dereference: Dereferencing a pointer that might be NULL ndev when calling is_vlan_dev. 1624 if (is_vlan_dev(ndev)) { Remove the manual implementation and use netdev_walk_all_lower_dev() to iterate over the lower devices. While on it remove an obsolete function parameter comment.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

4.18 ≤ v < 5.10.834.18 ≤ v < 5.15.64.18 ≤ v < 5.165.11 ≤ v < 5.15.64.18cb9d43f6775457cac75544bc4197f26ac2b6f294
Vendor states this is fixed in 587acad41f1bc48e16f42bb2aca63bf323380be8 (fixed)
Vendor states this is fixed in bb851d0fb02547d03cd40106b5f2391c4fed6ed1 (fixed)
Vendor states this is fixed in c94cbd262b6aa3b54d73a1ed1f9c0d19df57f4ff (fixed)
Vendor states this is fixed in 4.18 (unaffected)
Vendor states this is fixed in 5.10.83 (unaffected)
Vendor states this is fixed in 5.15.6 (unaffected)
Vendor states this is fixed in 5.16 (unaffected)

References (3)

Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/587acad41f1bc48e16f42bb2aca63bf323380be8
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/bb851d0fb02547d03cd40106b5f2391c4fed6ed1
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/c94cbd262b6aa3b54d73a1ed1f9c0d19df57f4ff

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-476

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