cbcvebase.
CVE-2024-35884
published 2024-05-19

CVE-2024-35884: In the Linux kernel, the following vulnerability has been resolved: udp: do not accept non-tunnel GSO skbs landing in a tunnel When rx-udp-gro-forwarding is…

PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.67%
48.4th percentile
In the Linux kernel, the following vulnerability has been resolved: udp: do not accept non-tunnel GSO skbs landing in a tunnel When rx-udp-gro-forwarding is enabled UDP packets might be GROed when being forwarded. If such packets might land in a tunnel this can cause various issues and udp_gro_receive makes sure this isn't the case by looking for a matching socket. This is performed in udp4/6_gro_lookup_skb but only in the current netns. This is an issue with tunneled packets when the endpoint is in another netns. In such cases the packets will be GROed at the UDP level, which leads to various issues later on. The same thing can happen with rx-gro-list. We saw this with geneve packets being GROed at the UDP level. In such case gso_size is set; later the packet goes through the geneve rx path, the geneve header is pulled, the offset are adjusted and frag_list skbs are not adjusted with regard to geneve. When those skbs hit skb_fragment, it will misbehave. Different outcomes are possible depending on what the GROed skbs look like; from corrupted packets to kernel crashes. One example is a BUG_ON[1] triggered in skb_segment while processing the frag_list. Because gso_size is wrong (geneve header was pulled) skb_segment thinks there is "geneve header size" of data in frag_list, although it's in fact the next packet. The BUG_ON itself has nothing to do with the issue. This is only one of the potential issues. Looking up for a matching socket in udp_gro_receive is fragile: the lookup could be extended to all netns (not speaking about performances) but nothing prevents those packets from being modified in between and we could still not find a matching socket. It's OK to keep the current logic there as it should cover most cases but we also need to make sure we handle tunnel packets being GROed too early. This is done by extending the checks in udp_unexpected_gso: GSO packets lacking the SKB_GSO_UDP_TUNNEL/_CSUM bits and landing in a tunnel must be segmented. [1] ker

Affected

22 ranges
VendorProductVersion rangeFixed in
debiandebian_linux
debianlinux< linux 6.1.85-1 (bookworm)linux 6.1.85-1 (bookworm)
linuxlinux
linuxlinux>= 9fd1ff5d2ac7181844735806b0a703c942365291 < 3391b157780bbedf8ef9f202cbf10ee90bf6b0f83391b157780bbedf8ef9f202cbf10ee90bf6b0f8
linuxlinux>= 9fd1ff5d2ac7181844735806b0a703c942365291 < d49ae15a5767d4e9ef8bbb79e42df1bfebc94670d49ae15a5767d4e9ef8bbb79e42df1bfebc94670
linuxlinux>= 9fd1ff5d2ac7181844735806b0a703c942365291 < d12245080cb259d82b34699f6cd4ec11bdb688bdd12245080cb259d82b34699f6cd4ec11bdb688bd
linuxlinux>= 9fd1ff5d2ac7181844735806b0a703c942365291 < 3001e7aa43d6691db2a878b0745b854bf12ddd193001e7aa43d6691db2a878b0745b854bf12ddd19
linuxlinux>= 9fd1ff5d2ac7181844735806b0a703c942365291 < 35fe0e0b5c00bef7dde74842a2564c43856fbce435fe0e0b5c00bef7dde74842a2564c43856fbce4
linuxlinux>= 9fd1ff5d2ac7181844735806b0a703c942365291 < 3d010c8031e39f5fa1e8b13ada77e0321091011f3d010c8031e39f5fa1e8b13ada77e0321091011f
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.216-15.10.216-1
linuxlinux_kernel>= 0 < 6.1.85-16.1.85-1
linuxlinux_kernel>= 0 < 6.8.9-16.8.9-1
linuxlinux_kernel>= 0 < 6.8.9-16.8.9-1
linuxlinux_kernel>= 0 < 5.15.0-116.1265.15.0-116.126
linuxlinux_kernel>= 0 < 6.8.0-38.386.8.0-38.38
linuxlinux_kernel>= 5.11 < 5.15.1545.15.154
linuxlinux_kernel>= 5.16 < 6.1.856.1.85
linuxlinux_kernel>= 5.6 < 5.10.2155.10.215
linuxlinux_kernel>= 6.2 < 6.6.266.6.26
linuxlinux_kernel>= 6.7 < 6.8.56.8.5

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv6.8MEDIUM
vendor_ubuntu6.3MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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