GHSA-WM5W-7H48-37X2
Vulnerability from github – Published: 2025-12-30 15:30 – Updated: 2025-12-30 15:30In the Linux kernel, the following vulnerability has been resolved:
ipv6: Fix an uninit variable access bug in __ip6_make_skb()
Syzbot reported a bug as following:
===================================================== BUG: KMSAN: uninit-value in arch_atomic64_inc arch/x86/include/asm/atomic64_64.h:88 [inline] BUG: KMSAN: uninit-value in arch_atomic_long_inc include/linux/atomic/atomic-long.h:161 [inline] BUG: KMSAN: uninit-value in atomic_long_inc include/linux/atomic/atomic-instrumented.h:1429 [inline] BUG: KMSAN: uninit-value in __ip6_make_skb+0x2f37/0x30f0 net/ipv6/ip6_output.c:1956 arch_atomic64_inc arch/x86/include/asm/atomic64_64.h:88 [inline] arch_atomic_long_inc include/linux/atomic/atomic-long.h:161 [inline] atomic_long_inc include/linux/atomic/atomic-instrumented.h:1429 [inline] __ip6_make_skb+0x2f37/0x30f0 net/ipv6/ip6_output.c:1956 ip6_finish_skb include/net/ipv6.h:1122 [inline] ip6_push_pending_frames+0x10e/0x550 net/ipv6/ip6_output.c:1987 rawv6_push_pending_frames+0xb12/0xb90 net/ipv6/raw.c:579 rawv6_sendmsg+0x297e/0x2e60 net/ipv6/raw.c:922 inet_sendmsg+0x101/0x180 net/ipv4/af_inet.c:827 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] _syssendmsg+0xa8e/0xe70 net/socket.c:2476 _sys_sendmsg+0x2a1/0x3f0 net/socket.c:2530 __sys_sendmsg net/socket.c:2559 [inline] __do_sys_sendmsg net/socket.c:2568 [inline] __se_sys_sendmsg net/socket.c:2566 [inline] __x64_sys_sendmsg+0x367/0x540 net/socket.c:2566 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd
Uninit was created at: slab_post_alloc_hook mm/slab.h:766 [inline] slab_alloc_node mm/slub.c:3452 [inline] __kmem_cache_alloc_node+0x71f/0xce0 mm/slub.c:3491 __do_kmalloc_node mm/slab_common.c:967 [inline] __kmalloc_node_track_caller+0x114/0x3b0 mm/slab_common.c:988 kmalloc_reserve net/core/skbuff.c:492 [inline] __alloc_skb+0x3af/0x8f0 net/core/skbuff.c:565 alloc_skb include/linux/skbuff.h:1270 [inline] __ip6_append_data+0x51c1/0x6bb0 net/ipv6/ip6_output.c:1684 ip6_append_data+0x411/0x580 net/ipv6/ip6_output.c:1854 rawv6_sendmsg+0x2882/0x2e60 net/ipv6/raw.c:915 inet_sendmsg+0x101/0x180 net/ipv4/af_inet.c:827 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] _syssendmsg+0xa8e/0xe70 net/socket.c:2476 _sys_sendmsg+0x2a1/0x3f0 net/socket.c:2530 __sys_sendmsg net/socket.c:2559 [inline] __do_sys_sendmsg net/socket.c:2568 [inline] __se_sys_sendmsg net/socket.c:2566 [inline] __x64_sys_sendmsg+0x367/0x540 net/socket.c:2566 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd
It is because icmp6hdr does not in skb linear region under the scenario of SOCK_RAW socket. Access icmp6_hdr(skb)->icmp6_type directly will trigger the uninit variable access bug.
Use a local variable icmp6_type to carry the correct value in different scenarios.
{
"affected": [],
"aliases": [
"CVE-2023-54265"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-12-30T13:16:15Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: Fix an uninit variable access bug in __ip6_make_skb()\n\nSyzbot reported a bug as following:\n\n=====================================================\nBUG: KMSAN: uninit-value in arch_atomic64_inc arch/x86/include/asm/atomic64_64.h:88 [inline]\nBUG: KMSAN: uninit-value in arch_atomic_long_inc include/linux/atomic/atomic-long.h:161 [inline]\nBUG: KMSAN: uninit-value in atomic_long_inc include/linux/atomic/atomic-instrumented.h:1429 [inline]\nBUG: KMSAN: uninit-value in __ip6_make_skb+0x2f37/0x30f0 net/ipv6/ip6_output.c:1956\n arch_atomic64_inc arch/x86/include/asm/atomic64_64.h:88 [inline]\n arch_atomic_long_inc include/linux/atomic/atomic-long.h:161 [inline]\n atomic_long_inc include/linux/atomic/atomic-instrumented.h:1429 [inline]\n __ip6_make_skb+0x2f37/0x30f0 net/ipv6/ip6_output.c:1956\n ip6_finish_skb include/net/ipv6.h:1122 [inline]\n ip6_push_pending_frames+0x10e/0x550 net/ipv6/ip6_output.c:1987\n rawv6_push_pending_frames+0xb12/0xb90 net/ipv6/raw.c:579\n rawv6_sendmsg+0x297e/0x2e60 net/ipv6/raw.c:922\n inet_sendmsg+0x101/0x180 net/ipv4/af_inet.c:827\n sock_sendmsg_nosec net/socket.c:714 [inline]\n sock_sendmsg net/socket.c:734 [inline]\n ____sys_sendmsg+0xa8e/0xe70 net/socket.c:2476\n ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2530\n __sys_sendmsg net/socket.c:2559 [inline]\n __do_sys_sendmsg net/socket.c:2568 [inline]\n __se_sys_sendmsg net/socket.c:2566 [inline]\n __x64_sys_sendmsg+0x367/0x540 net/socket.c:2566\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nUninit was created at:\n slab_post_alloc_hook mm/slab.h:766 [inline]\n slab_alloc_node mm/slub.c:3452 [inline]\n __kmem_cache_alloc_node+0x71f/0xce0 mm/slub.c:3491\n __do_kmalloc_node mm/slab_common.c:967 [inline]\n __kmalloc_node_track_caller+0x114/0x3b0 mm/slab_common.c:988\n kmalloc_reserve net/core/skbuff.c:492 [inline]\n __alloc_skb+0x3af/0x8f0 net/core/skbuff.c:565\n alloc_skb include/linux/skbuff.h:1270 [inline]\n __ip6_append_data+0x51c1/0x6bb0 net/ipv6/ip6_output.c:1684\n ip6_append_data+0x411/0x580 net/ipv6/ip6_output.c:1854\n rawv6_sendmsg+0x2882/0x2e60 net/ipv6/raw.c:915\n inet_sendmsg+0x101/0x180 net/ipv4/af_inet.c:827\n sock_sendmsg_nosec net/socket.c:714 [inline]\n sock_sendmsg net/socket.c:734 [inline]\n ____sys_sendmsg+0xa8e/0xe70 net/socket.c:2476\n ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2530\n __sys_sendmsg net/socket.c:2559 [inline]\n __do_sys_sendmsg net/socket.c:2568 [inline]\n __se_sys_sendmsg net/socket.c:2566 [inline]\n __x64_sys_sendmsg+0x367/0x540 net/socket.c:2566\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nIt is because icmp6hdr does not in skb linear region under the scenario\nof SOCK_RAW socket. Access icmp6_hdr(skb)-\u003eicmp6_type directly will\ntrigger the uninit variable access bug.\n\nUse a local variable icmp6_type to carry the correct value in different\nscenarios.",
"id": "GHSA-wm5w-7h48-37x2",
"modified": "2025-12-30T15:30:34Z",
"published": "2025-12-30T15:30:34Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-54265"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/02ed5700f40445af02d1c97db25ffc2d04971d9f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/0cf600ca1bdf1d52df977516ee6cee0cadb1f6b1"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/165370522cc48127da564a08584a7391e6341908"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2c9cefc142c1dc2759e19a92d3b2b3715e985beb"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/605b056d63302ae84eb136e88d4df49124bd5e0d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d65ff2fe877c471aa6e79efa7bd8ff66e147c317"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ea30388baebcce37fd594d425a65037ca35e59e8"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f394f690a30a5ec0413c62777a058eaf3d6e10d5"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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