{"id":"DEBIAN-CVE-2023-54265","details":"In 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]  ____sys_sendmsg+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]  ____sys_sendmsg+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)-\u003eicmp6_type directly will trigger the uninit variable access bug.  Use a local variable icmp6_type to carry the correct value in different scenarios.","modified":"2026-09-15T08:47:30.310731743Z","published":"2025-12-30T13:16:15.300Z","upstream":["CVE-2023-54265"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2023-54265"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.25-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2023-54265.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.25-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2023-54265.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.25-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2023-54265.json"}}],"schema_version":"1.9.0"}