{
  "threat_severity" : "Low",
  "public_date" : "2024-07-29T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: udp: Set SOCK_RCU_FREE earlier in udp_lib_get_port()",
    "id" : "2300410",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2300410"
  },
  "cvss3" : {
    "cvss3_base_score" : "4.7",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-911",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nudp: Set SOCK_RCU_FREE earlier in udp_lib_get_port().\nsyzkaller triggered the warning [0] in udp_v4_early_demux().\nIn udp_v[46]_early_demux() and sk_lookup(), we do not touch the refcount\nof the looked-up sk and use sock_pfree() as skb->destructor, so we check\nSOCK_RCU_FREE to ensure that the sk is safe to access during the RCU grace\nperiod.\nCurrently, SOCK_RCU_FREE is flagged for a bound socket after being put\ninto the hash table.  Moreover, the SOCK_RCU_FREE check is done too early\nin udp_v[46]_early_demux() and sk_lookup(), so there could be a small race\nwindow:\nCPU1                                 CPU2\n----                                 ----\nudp_v4_early_demux()                 udp_lib_get_port()\n|                                    |- hlist_add_head_rcu()\n|- sk = __udp4_lib_demux_lookup()    |\n|- DEBUG_NET_WARN_ON_ONCE(sk_is_refcounted(sk));\n`- sock_set_flag(sk, SOCK_RCU_FREE)\nWe had the same bug in TCP and fixed it in commit 871019b22d1b (\"net:\nset SOCK_RCU_FREE before inserting socket into hashtable\").\nLet's apply the same fix for UDP.\n[0]:\nWARNING: CPU: 0 PID: 11198 at net/ipv4/udp.c:2599 udp_v4_early_demux+0x481/0xb70 net/ipv4/udp.c:2599\nModules linked in:\nCPU: 0 PID: 11198 Comm: syz-executor.1 Not tainted 6.9.0-g93bda33046e7 #13\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014\nRIP: 0010:udp_v4_early_demux+0x481/0xb70 net/ipv4/udp.c:2599\nCode: c5 7a 15 fe bb 01 00 00 00 44 89 e9 31 ff d3 e3 81 e3 bf ef ff ff 89 de e8 2c 74 15 fe 85 db 0f 85 02 06 00 00 e8 9f 7a 15 fe <0f> 0b e8 98 7a 15 fe 49 8d 7e 60 e8 4f 39 2f fe 49 c7 46 60 20 52\nRSP: 0018:ffffc9000ce3fa58 EFLAGS: 00010293\nRAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8318c92c\nRDX: ffff888036ccde00 RSI: ffffffff8318c2f1 RDI: 0000000000000001\nRBP: ffff88805a2dd6e0 R08: 0000000000000001 R09: 0000000000000000\nR10: 0000000000000000 R11: 0001ffffffffffff R12: ffff88805a2dd680\nR13: 0000000000000007 R14: ffff88800923f900 R15: ffff88805456004e\nFS:  00007fc449127640(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00007fc449126e38 CR3: 000000003de4b002 CR4: 0000000000770ef0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600\nPKRU: 55555554\nCall Trace:\n<TASK>\nip_rcv_finish_core.constprop.0+0xbdd/0xd20 net/ipv4/ip_input.c:349\nip_rcv_finish+0xda/0x150 net/ipv4/ip_input.c:447\nNF_HOOK include/linux/netfilter.h:314 [inline]\nNF_HOOK include/linux/netfilter.h:308 [inline]\nip_rcv+0x16c/0x180 net/ipv4/ip_input.c:569\n__netif_receive_skb_one_core+0xb3/0xe0 net/core/dev.c:5624\n__netif_receive_skb+0x21/0xd0 net/core/dev.c:5738\nnetif_receive_skb_internal net/core/dev.c:5824 [inline]\nnetif_receive_skb+0x271/0x300 net/core/dev.c:5884\ntun_rx_batched drivers/net/tun.c:1549 [inline]\ntun_get_user+0x24db/0x2c50 drivers/net/tun.c:2002\ntun_chr_write_iter+0x107/0x1a0 drivers/net/tun.c:2048\nnew_sync_write fs/read_write.c:497 [inline]\nvfs_write+0x76f/0x8d0 fs/read_write.c:590\nksys_write+0xbf/0x190 fs/read_write.c:643\n__do_sys_write fs/read_write.c:655 [inline]\n__se_sys_write fs/read_write.c:652 [inline]\n__x64_sys_write+0x41/0x50 fs/read_write.c:652\nx64_sys_call+0xe66/0x1990 arch/x86/include/generated/asm/syscalls_64.h:2\ndo_syscall_x64 arch/x86/entry/common.c:52 [inline]\ndo_syscall_64+0x4b/0x110 arch/x86/entry/common.c:83\nentry_SYSCALL_64_after_hwframe+0x4b/0x53\nRIP: 0033:0x7fc44a68bc1f\nCode: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 e9 cf f5 ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 3c d0 f5 ff 48\nRSP: 002b:00007fc449126c90 EFLAGS: 00000293 ORIG_RAX: 0000000000000001\nRAX: ffffffffffffffda RBX: 00000000004bc050 RCX: 00007fc44a68bc1f\nR\n---truncated---" ],
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2024-09-24T00:00:00Z",
    "advisory" : "RHSA-2024:7001",
    "cpe" : "cpe:/a:redhat:enterprise_linux:8::nfv",
    "package" : "kernel-rt-0:4.18.0-553.22.1.rt7.363.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2024-09-24T00:00:00Z",
    "advisory" : "RHSA-2024:7000",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-553.22.1.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.8 Extended Update Support",
    "release_date" : "2024-09-24T00:00:00Z",
    "advisory" : "RHSA-2024:6993",
    "cpe" : "cpe:/o:redhat:rhel_eus:8.8",
    "package" : "kernel-0:4.18.0-477.74.1.el8_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2024-08-28T00:00:00Z",
    "advisory" : "RHSA-2024:5928",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-427.33.1.el9_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2024-08-28T00:00:00Z",
    "advisory" : "RHSA-2024:5928",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-427.33.1.el9_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.2 Extended Update Support",
    "release_date" : "2024-12-04T00:00:00Z",
    "advisory" : "RHSA-2024:10772",
    "cpe" : "cpe:/a:redhat:rhel_eus:9.2",
    "package" : "kernel-0:5.14.0-284.95.1.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.2 Extended Update Support",
    "release_date" : "2024-12-04T00:00:00Z",
    "advisory" : "RHSA-2024:10773",
    "cpe" : "cpe:/a:redhat:rhel_eus:9.2::nfv",
    "package" : "kernel-rt-0:5.14.0-284.95.1.rt14.380.el9_2"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2024-41041\nhttps://nvd.nist.gov/vuln/detail/CVE-2024-41041\nhttps://lore.kernel.org/linux-cve-announce/2024072924-CVE-2024-41041-ae0c@gregkh/T" ],
  "name" : "CVE-2024-41041",
  "csaw" : false
}