Riskcovery

CVE-2021-47223

net: bridge: fix vlan tunnel dst null pointer dereference

State
Published
Severity
Not scored
Published
May 21, 2024
Updated
May 11, 2026
Reserved
Apr 10, 2024

Read the record on cve.org

Description

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

net: bridge: fix vlan tunnel dst null pointer dereference

This patch fixes a tunnel_dst null pointer dereference due to lockless access in the tunnel egress path. When deleting a vlan tunnel the tunnel_dst pointer is set to NULL without waiting a grace period (i.e. while it's still usable) and packets egressing are dereferencing it without checking. Use READ/WRITE_ONCE to annotate the lockless use of tunnel_id, use RCU for accessing tunnel_dst and make sure it is read only once and checked in the egress path. The dst is already properly RCU protected so we don't need to do anything fancy than to make sure tunnel_id and tunnel_dst are read only once and checked in the egress path.

Scores

The record has no CVSS score.

Weaknesses

The record names no weakness.

Affected Products

ProductVersions
LinuxLinux
  • 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd to before ad7feefe7164892db424c45687472db803d87f79Affected
  • 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd to before 24a6e55f17aa123bc1fc54b7d3c410b41bc16530Affected
  • 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd to before a2241e62f6b4a774d8a92048fdf59c45f6c2fe5cAffected
  • 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd to before fe0448a3fad365a747283a00a1d1ad5e8d6675b7Affected
  • 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd to before abb02e05cb1c0a30dd873a29f33bc092067dc35dAffected
  • 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd to before 58e2071742e38f29f051b709a5cca014ba51166fAffected
LinuxLinux
  • 4.11Affected
  • before 4.11Not affected
  • 4.14.238 through 4.14.*Not affected
  • 4.19.196 through 4.19.*Not affected
  • 5.4.128 through 5.4.*Not affected
  • 5.10.46 through 5.10.*Not affected
  • 5.12.13 through 5.12.*Not affected
  • 5.13 and laterNot affected

References

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