cbcvebase.
CVE-2021-47223
published 2024-05-21

CVE-2021-47223: 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…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.24%
14.7th percentile
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.

Affected

18 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.10.46-1 (bookworm)linux 5.10.46-1 (bookworm)
linuxlinux
linuxlinux>= 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd < ad7feefe7164892db424c45687472db803d87f79ad7feefe7164892db424c45687472db803d87f79
linuxlinux>= 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd < 24a6e55f17aa123bc1fc54b7d3c410b41bc1653024a6e55f17aa123bc1fc54b7d3c410b41bc16530
linuxlinux>= 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd < a2241e62f6b4a774d8a92048fdf59c45f6c2fe5ca2241e62f6b4a774d8a92048fdf59c45f6c2fe5c
linuxlinux>= 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd < fe0448a3fad365a747283a00a1d1ad5e8d6675b7fe0448a3fad365a747283a00a1d1ad5e8d6675b7
linuxlinux>= 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd < abb02e05cb1c0a30dd873a29f33bc092067dc35dabb02e05cb1c0a30dd873a29f33bc092067dc35d
linuxlinux>= 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd < 58e2071742e38f29f051b709a5cca014ba51166f58e2071742e38f29f051b709a5cca014ba51166f
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 4.11 < 4.14.2384.14.238
linuxlinux_kernel>= 4.15 < 4.19.1964.19.196
linuxlinux_kernel>= 4.20 < 5.4.1285.4.128
linuxlinux_kernel>= 5.11 < 5.12.135.12.13
linuxlinux_kernel>= 5.5 < 5.10.465.10.46

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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