)]}'
{
  "commit": "e99d24367a9c6985bc9c997c6f3a053c2a7e2eff",
  "tree": "2219906b3aac294f14fe554e2b2c4704ccf6ba53",
  "parents": [
    "da0892c7b46b1ea2a59a48f1b59d0e63e53f0b81"
  ],
  "author": {
    "name": "Shigeru Yoshida",
    "email": "syoshida@redhat.com",
    "time": "Tue Apr 30 21:39:45 2024 +0900"
  },
  "committer": {
    "name": "He Gao",
    "email": "hegao@google.com",
    "time": "Fri May 30 16:49:34 2025 -0700"
  },
  "message": "ipv4: Fix uninit-value access in __ip_make_skb()\n\ncommit fc1092f51567277509563800a3c56732070b6aa4 upstream.\n\nKMSAN reported uninit-value access in __ip_make_skb() [1].  __ip_make_skb()\ntests HDRINCL to know if the skb has icmphdr. However, HDRINCL can cause a\nrace condition. If calling setsockopt(2) with IP_HDRINCL changes HDRINCL\nwhile __ip_make_skb() is running, the function will access icmphdr in the\nskb even if it is not included. This causes the issue reported by KMSAN.\n\nCheck FLOWI_FLAG_KNOWN_NH on fl4-\u003eflowi4_flags instead of testing HDRINCL\non the socket.\n\nAlso, fl4-\u003efl4_icmp_type and fl4-\u003efl4_icmp_code are not initialized. These\nare union in struct flowi4 and are implicitly initialized by\nflowi4_init_output(), but we should not rely on specific union layout.\n\nInitialize these explicitly in raw_sendmsg().\n\n[1]\nBUG: KMSAN: uninit-value in __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481\n __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481\n ip_finish_skb include/net/ip.h:243 [inline]\n ip_push_pending_frames+0x4c/0x5c0 net/ipv4/ip_output.c:1508\n raw_sendmsg+0x2381/0x2690 net/ipv4/raw.c:654\n inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851\n sock_sendmsg_nosec net/socket.c:730 [inline]\n __sock_sendmsg+0x274/0x3c0 net/socket.c:745\n __sys_sendto+0x62c/0x7b0 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+0x130/0x200 net/socket.c:2199\n do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83\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+0x5f6/0xc50 mm/slub.c:3888\n kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:577\n __alloc_skb+0x35a/0x7c0 net/core/skbuff.c:668\n alloc_skb include/linux/skbuff.h:1318 [inline]\n __ip_append_data+0x49ab/0x68c0 net/ipv4/ip_output.c:1128\n ip_append_data+0x1e7/0x260 net/ipv4/ip_output.c:1365\n raw_sendmsg+0x22b1/0x2690 net/ipv4/raw.c:648\n inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851\n sock_sendmsg_nosec net/socket.c:730 [inline]\n __sock_sendmsg+0x274/0x3c0 net/socket.c:745\n __sys_sendto+0x62c/0x7b0 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+0x130/0x200 net/socket.c:2199\n do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x6d/0x75\n\nCPU: 1 PID: 15709 Comm: syz-executor.7 Not tainted 6.8.0-11567-gb3603fcb79b1 #25\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014\n\nBUG\u003db/394276167\nTEST\u003dpresubmit\nRELEASE_NOTE\u003dFixed CVE-2024-36927 in the Linux kernel.\n\ncos-patch: security-moderate\nFixes: 99e5acae193e (\"ipv4: Fix potential uninit variable access bug in __ip_make_skb()\")\nReported-by: syzkaller \u003csyzkaller@googlegroups.com\u003e\nChange-Id: Icfeb9d82dd441f9c0d5a8e968df096ab709b6b7a\nSigned-off-by: Shigeru Yoshida \u003csyoshida@redhat.com\u003e\nLink: https://lore.kernel.org/r/20240430123945.2057348-1-syoshida@redhat.com\nSigned-off-by: Paolo Abeni \u003cpabeni@redhat.com\u003e\nSigned-off-by: Zhaoyang Li \u003clizy04@hust.edu.cn\u003e\nSigned-off-by: Greg Kroah-Hartman \u003cgregkh@linuxfoundation.org\u003e\nSigned-off-by: Kernel CVE Triage Automation \u003ccloud-image-kernel-cve-triage-automation@prod.google.com\u003e\nReviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/103506\nReviewed-by: He Gao \u003chegao@google.com\u003e\nTested-by: Cusky Presubmit Bot \u003cpresubmit@cos-infra-prod.iam.gserviceaccount.com\u003e\nReviewed-by: Miri Amarilio \u003cmirilio@google.com\u003e\n",
  "tree_diff": [
    {
      "type": "modify",
      "old_id": "c82107bbd98102f265dbc1bd3990d4caea3eef8d",
      "old_mode": 33188,
      "old_path": "net/ipv4/ip_output.c",
      "new_id": "543d029102cfa1294959723ee6cb4b63cd3db93c",
      "new_mode": 33188,
      "new_path": "net/ipv4/ip_output.c"
    },
    {
      "type": "modify",
      "old_id": "ee0efd0efec400b24212319d25f2a08b24b58935",
      "old_mode": 33188,
      "old_path": "net/ipv4/raw.c",
      "new_id": "c109bc376cc53568879d61a5ff3e72c687a9ac2c",
      "new_mode": 33188,
      "new_path": "net/ipv4/raw.c"
    }
  ]
}