ghsa-hv5r-r2vq-gcrh
Vulnerability from github
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()) uses skb_protocol(skb, true), pskb_inet_may_pull() is only using skb->protocol.
If anything else than ETH_P_IPV6 or ETH_P_IP is found in skb->protocol, pskb_inet_may_pull() does nothing at all.
If a vlan tag was provided by the caller (af_packet in the syzbot case), the network header might not point to the correct location, and skb linear part could be smaller than expected.
Add skb_vlan_inet_prepare() to perform a complete mac validation.
Use this in geneve for the moment, I suspect we need to adopt this more broadly.
v4 - Jakub reported v3 broke l2_tos_ttl_inherit.sh selftest - Only call __vlan_get_protocol() for vlan types.
v2,v3 - Addressed Sabrina comments on v1 and v2
[1]
BUG: KMSAN: uninit-value in geneve_xmit_skb drivers/net/geneve.c:910 [inline] BUG: KMSAN: uninit-value in geneve_xmit+0x302d/0x5420 drivers/net/geneve.c:1030 geneve_xmit_skb drivers/net/geneve.c:910 [inline] geneve_xmit+0x302d/0x5420 drivers/net/geneve.c:1030 __netdev_start_xmit include/linux/netdevice.h:4903 [inline] netdev_start_xmit include/linux/netdevice.h:4917 [inline] xmit_one net/core/dev.c:3531 [inline] dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3547 __dev_queue_xmit+0x348d/0x52c0 net/core/dev.c:4335 dev_queue_xmit include/linux/netdevice.h:3091 [inline] packet_xmit+0x9c/0x6c0 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3081 [inline] packet_sendmsg+0x8bb0/0x9ef0 net/packet/af_packet.c:3113 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x30f/0x380 net/socket.c:745 __sys_sendto+0x685/0x830 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x125/0x1d0 net/socket.c:2199 do_syscall_64+0xd5/0x1f0 entry_SYSCALL_64_after_hwframe+0x6d/0x75
Uninit was created at: slab_post_alloc_hook mm/slub.c:3804 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc_node+0x613/0xc50 mm/slub.c:3888 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:577 __alloc_skb+0x35b/0x7a0 net/core/skbuff.c:668 alloc_skb include/linux/skbuff.h:1318 [inline] alloc_skb_with_frags+0xc8/0xbf0 net/core/skbuff.c:6504 sock_alloc_send_pskb+0xa81/0xbf0 net/core/sock.c:2795 packet_alloc_skb net/packet/af_packet.c:2930 [inline] packet_snd net/packet/af_packet.c:3024 [inline] packet_sendmsg+0x722d/0x9ef0 net/packet/af_packet.c:3113 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x30f/0x380 net/socket.c:745 __sys_sendto+0x685/0x830 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x125/0x1d0 net/socket.c:2199 do_syscall_64+0xd5/0x1f0 entry_SYSCALL_64_after_hwframe+0x6d/0x75
CPU: 0 PID: 5033 Comm: syz-executor346 Not tainted 6.9.0-rc1-syzkaller-00005-g928a87efa423 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
{
"affected": [],
"aliases": [
"CVE-2024-35973"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-20T10:15:12Z",
"severity": null
},
"details": "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-\u003eprotocol.\n\nIf anything else than ETH_P_IPV6 or ETH_P_IP is found in skb-\u003eprotocol,\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",
"id": "GHSA-hv5r-r2vq-gcrh",
"modified": "2024-06-27T12:30:46Z",
"published": "2024-05-20T12:30:28Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-35973"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/10204df9beda4978bd1d0c2db0d8375bfb03b915"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/190d9efa5773f26d6f334b1b8be282c4fa13fd5e"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/357163fff3a6e48fe74745425a32071ec9caf852"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3c1ae6de74e3d2d6333d29a2d3e13e6094596c79"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/43be590456e1f3566054ce78ae2dbb68cbe1a536"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/4a1b65d1e55d53b397cb27014208be1e04172670"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d3adf11d7993518a39bd02b383cfe657ccc0023c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d8a6213d70accb403b82924a1c229e733433a5ef"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html"
}
],
"schema_version": "1.4.0",
"severity": []
}