{"id":"CVE-2024-35973","url":"https://www.cyber-defence.io/tools/cve/CVE-2024-35973","generatedAt":"2026-10-27T23:58:11.107Z","title":"In the Linux kernel, the following vulnerability has been resolved: geneve: fix header validation in geneve[6]_xmit_skb syzbot is able to trigger an uninit-value in geneve_xmit() [1] Problem : While most ip tunnel helpers (like ip_tunnel_get_dsfield())…","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","published":"2024-05-20T10:15:12.000Z","lastModified":"2026-10-15T01:18:15.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-908"],"affected":["linux/linux kernel","debian/debian linux"],"epss":{"score":0.00252,"percentile":0.16516,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.25%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/10204df9beda4978bd1d0c2db0d8375bfb03b915","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/190d9efa5773f26d6f334b1b8be282c4fa13fd5e","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/357163fff3a6e48fe74745425a32071ec9caf852","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/3c1ae6de74e3d2d6333d29a2d3e13e6094596c79","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/43be590456e1f3566054ce78ae2dbb68cbe1a536","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4a1b65d1e55d53b397cb27014208be1e04172670","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d3adf11d7993518a39bd02b383cfe657ccc0023c","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d8a6213d70accb403b82924a1c229e733433a5ef","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/10204df9beda4978bd1d0c2db0d8375bfb03b915","tags":["Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/190d9efa5773f26d6f334b1b8be282c4fa13fd5e","tags":["Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/357163fff3a6e48fe74745425a32071ec9caf852","tags":["Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/3c1ae6de74e3d2d6333d29a2d3e13e6094596c79","tags":["Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/43be590456e1f3566054ce78ae2dbb68cbe1a536","tags":["Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/4a1b65d1e55d53b397cb27014208be1e04172670","tags":["Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/d3adf11d7993518a39bd02b383cfe657ccc0023c","tags":["Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/d8a6213d70accb403b82924a1c229e733433a5ef","tags":["Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-265688.html","source":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-613116.html","source":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2024-35973","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}