cbcvebase.
CVE-2022-49340
published 2025-02-26

CVE-2022-49340: In the Linux kernel, the following vulnerability has been resolved: ip_gre: test csum_start instead of transport header GRE with TUNNEL_CSUM will apply local…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.28%
20.4th percentile
In the Linux kernel, the following vulnerability has been resolved: ip_gre: test csum_start instead of transport header GRE with TUNNEL_CSUM will apply local checksum offload on CHECKSUM_PARTIAL packets. ipgre_xmit must validate csum_start after an optional skb_pull, else lco_csum may trigger an overflow. The original check was if (csum && skb_checksum_start(skb) data) return -EINVAL; This had false positives when skb_checksum_start is undefined: when ip_summed is not CHECKSUM_PARTIAL. A discussed refinement was straightforward if (csum && skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_start(skb) data) return -EINVAL; But was eventually revised more thoroughly: - restrict the check to the only branch where needed, in an uncommon GRE path that uses header_ops and calls skb_pull. - test skb_transport_header, which is set along with csum_start in skb_partial_csum_set in the normal header_ops datapath. Turns out skbs can arrive in this branch without the transport header set, e.g., through BPF redirection. Revise the check back to check csum_start directly, and only if CHECKSUM_PARTIAL. Do leave the check in the updated location. Check field regardless of whether TUNNEL_CSUM is configured.

Affected

25 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.18.5-1 (bookworm)linux 5.18.5-1 (bookworm)
linuxlinux——
linuxlinux——
linuxlinux>= 3d32ce5472bb2ca720bef84089b85f76a705fd1a < 3d08bc3a5d9b2106f5c8bcf1adb73147824aa0063d08bc3a5d9b2106f5c8bcf1adb73147824aa006
linuxlinux>= 4.19.207 < 4.19.2474.19.247
linuxlinux>= 5.10.68 < 5.10.1225.10.122
linuxlinux>= 5.14.7 < 5.155.15
linuxlinux>= 5.4.148 < 5.4.1985.4.198
linuxlinux>= 774430026bd9a472d08c5d3c33351a782315771a < 7596bd7920985f7fc8579a92e48bc53ce4475b217596bd7920985f7fc8579a92e48bc53ce4475b21
linuxlinux>= 87b34cd6485192777f632f92d592f2a71d8801a6 < fbeb8dfa8b87ef259eef0c89e39b53962a3cf604fbeb8dfa8b87ef259eef0c89e39b53962a3cf604
linuxlinux>= 8a0ed250f911da31a2aef52101bc707846a800ff < e6b6f98fc7605c06c0a3baa70f62c534d7b4ce58e6b6f98fc7605c06c0a3baa70f62c534d7b4ce58
linuxlinux>= 8a0ed250f911da31a2aef52101bc707846a800ff < 0c92d813c7c9ca2212ecd879232e7d87362fce980c92d813c7c9ca2212ecd879232e7d87362fce98
linuxlinux>= 8a0ed250f911da31a2aef52101bc707846a800ff < 0ffa268724656633af5f37a38c212326d98ebe8c0ffa268724656633af5f37a38c212326d98ebe8c
linuxlinux>= 8a0ed250f911da31a2aef52101bc707846a800ff < 8d21e9963bec1aad2280cdd034c8993033ef29488d21e9963bec1aad2280cdd034c8993033ef2948
linuxlinux_kernel——
linuxlinux_kernel>= 0 < 5.10.127-15.10.127-1
linuxlinux_kernel>= 0 < 5.18.5-15.18.5-1
linuxlinux_kernel>= 0 < 5.18.5-15.18.5-1
linuxlinux_kernel>= 0 < 5.18.5-15.18.5-1
linuxlinux_kernel>= 4.19.207 < 4.19.2474.19.247
linuxlinux_kernel>= 5.10.68 < 5.10.1225.10.122
linuxlinux_kernel>= 5.14.7 < 5.15.475.15.47
linuxlinux_kernel>= 5.16 < 5.17.155.17.15
linuxlinux_kernel>= 5.18 < 5.18.45.18.4
linuxlinux_kernel>= 5.4.148 < 5.4.1985.4.198

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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