{"cve":"CVE-2024-35973","nvd":{"published":"2024-05-20T10:15:12.077","modified":"2026-10-15T01:18:15.077","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ngeneve: fix header validation in geneve[6]_xmit_skb\n\nsyzbot is able to trigger an uninit-value in geneve_xmit() [1]\n\nProblem : While most ip tunnel helpers (like ip_tunnel_get_dsfield())\nuses skb_protocol(skb, true), pskb_inet_may_pull() is only using\nskb->protocol.\n\nIf anything else than ETH_P_IPV6 or ETH_P_IP is found in skb->protocol,\npskb_inet_may_pull() does nothing at all.\n\nIf a vlan tag was provided by the caller (af_packet in the syzbot case),\nthe network header might not point to the correct location, and skb\nlinear part could be smaller than expected.\n\nAdd skb_vlan_inet_prepare() to perform a complete mac validation.\n\nUse this in geneve for the moment, I suspect we need to adopt this\nmore broadly.\n\nv4 - Jakub reported v3 broke l2_tos_ttl_inherit.sh selftest\n   - Only call __vlan_get_protocol() for vlan types.\n\nv2,v3 - Addressed Sabrina comments on v1 and v2\n\n[1]\n\nBUG: KMSAN: uninit-value in geneve_xmit_skb drivers/net/geneve.c:910 [inline]\n BUG: KMSAN: uninit-value in geneve_xmit+0x302d/0x5420 drivers/net/geneve.c:1030\n  geneve_xmit_skb drivers/net/geneve.c:910 [inline]\n  geneve_xmit+0x302d/0x5420 drivers/net/geneve.c:1030\n  __netdev_start_xmit include/linux/netdevice.h:4903 [inline]\n  netdev_start_xmit include/linux/netdevice.h:4917 [inline]\n  xmit_one net/core/dev.c:3531 [inline]\n  dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3547\n  __dev_queue_xmit+0x348d/0x52c0 net/core/dev.c:4335\n  dev_queue_xmit include/linux/netdevice.h:3091 [inline]\n  packet_xmit+0x9c/0x6c0 net/packet/af_packet.c:276\n  packet_snd net/packet/af_packet.c:3081 [inline]\n  packet_sendmsg+0x8bb0/0x9ef0 net/packet/af_packet.c:3113\n  sock_sendmsg_nosec net/socket.c:730 [inline]\n  __sock_sendmsg+0x30f/0x380 net/socket.c:745\n  __sys_sendto+0x685/0x830 net/socket.c:2191\n  __do_sys_sendto net/socket.c:2203 [inline]\n  __se_sys_sendto net/socket.c:2199 [inline]\n  __x64_sys_sendto+0x125/0x1d0 net/socket.c:2199\n do_syscall_64+0xd5/0x1f0\n entry_SYSCALL_64_after_hwframe+0x6d/0x75\n\nUninit was created at:\n  slab_post_alloc_hook mm/slub.c:3804 [inline]\n  slab_alloc_node mm/slub.c:3845 [inline]\n  kmem_cache_alloc_node+0x613/0xc50 mm/slub.c:3888\n  kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:577\n  __alloc_skb+0x35b/0x7a0 net/core/skbuff.c:668\n  alloc_skb include/linux/skbuff.h:1318 [inline]\n  alloc_skb_with_frags+0xc8/0xbf0 net/core/skbuff.c:6504\n  sock_alloc_send_pskb+0xa81/0xbf0 net/core/sock.c:2795\n  packet_alloc_skb net/packet/af_packet.c:2930 [inline]\n  packet_snd net/packet/af_packet.c:3024 [inline]\n  packet_sendmsg+0x722d/0x9ef0 net/packet/af_packet.c:3113\n  sock_sendmsg_nosec net/socket.c:730 [inline]\n  __sock_sendmsg+0x30f/0x380 net/socket.c:745\n  __sys_sendto+0x685/0x830 net/socket.c:2191\n  __do_sys_sendto net/socket.c:2203 [inline]\n  __se_sys_sendto net/socket.c:2199 [inline]\n  __x64_sys_sendto+0x125/0x1d0 net/socket.c:2199\n do_syscall_64+0xd5/0x1f0\n entry_SYSCALL_64_after_hwframe+0x6d/0x75\n\nCPU: 0 PID: 5033 Comm: syz-executor346 Not tainted 6.9.0-rc1-syzkaller-00005-g928a87efa423 #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-908"],"references":["https://git.kernel.org/stable/c/10204df9beda4978bd1d0c2db0d8375bfb03b915","https://git.kernel.org/stable/c/190d9efa5773f26d6f334b1b8be282c4fa13fd5e","https://git.kernel.org/stable/c/357163fff3a6e48fe74745425a32071ec9caf852","https://git.kernel.org/stable/c/3c1ae6de74e3d2d6333d29a2d3e13e6094596c79","https://git.kernel.org/stable/c/43be590456e1f3566054ce78ae2dbb68cbe1a536"],"products":["debian:debian_linux","linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2024-35973","score":0.00252,"percentile":0.16501,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}