Bug 2414506 (CVE-2025-40170)

Summary: CVE-2025-40170 kernel: net: use dst_dev_rcu() in sk_setup_caps()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Priority: medium    
Version: unspecifiedKeywords: Security
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OS: Linux   
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Description OSIDB Bzimport 2025-11-12 11:04:17 UTC 
In the Linux kernel, the following vulnerability has been resolved:

net: use dst_dev_rcu() in sk_setup_caps()

Use RCU to protect accesses to dst->dev from sk_setup_caps()
and sk_dst_gso_max_size().

Also use dst_dev_rcu() in ip6_dst_mtu_maybe_forward(),
and ip_dst_mtu_maybe_forward().

ip4_dst_hoplimit() can use dst_dev_net_rcu().
Comment 1 Alexander B 2025-11-13 13:53:43 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025111259-CVE-2025-40170-d39d@gregkh/T