CVE-2024-36927

CVE Details

Release Date:

2024-05-30

Description

In the Linux kernel, the following vulnerability has been resolved:\nipv4: Fix uninit-value access in __ip_make_skb()\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.\nCheck FLOWI_FLAG_KNOWN_NH on fl4->flowi4_flags instead of testing HDRINCL\non the socket.\nAlso, fl4->fl4_icmp_type and fl4->fl4_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.\nInitialize these explicitly in raw_sendmsg().\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\nip_finish_skb include/net/ip.h:243 [inline]\nip_push_pending_frames+0x4c/0x5c0 net/ipv4/ip_output.c:1508\nraw_sendmsg+0x2381/0x2690 net/ipv4/raw.c:654\ninet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851\nsock_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\ndo_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83\nentry_SYSCALL_64_after_hwframe+0x6d/0x75\nUninit was created at:\nslab_post_alloc_hook mm/slub.c:3804 [inline]\nslab_alloc_node mm/slub.c:3845 [inline]\nkmem_cache_alloc_node+0x5f6/0xc50 mm/slub.c:3888\nkmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:577\n__alloc_skb+0x35a/0x7c0 net/core/skbuff.c:668\nalloc_skb include/linux/skbuff.h:1318 [inline]\n__ip_append_data+0x49ab/0x68c0 net/ipv4/ip_output.c:1128\nip_append_data+0x1e7/0x260 net/ipv4/ip_output.c:1365\nraw_sendmsg+0x22b1/0x2690 net/ipv4/raw.c:648\ninet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851\nsock_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\ndo_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83\nentry_SYSCALL_64_after_hwframe+0x6d/0x75\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

See more information about CVE-2024-36927 from MITRE CVE dictionary and NIST NVD

CVSS Scoring

NOTE: The following CVSS v3.1 metrics and score provided are preliminary and subject to review.

Base Score:	5.5	CVSS Vector:	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector:	Local network	Attack Complexity:	Low
Privileges Required:	Low	User Interaction:	None
Scope:	Unchanged	Confidentiality Impact:	None
Integrity Impact:	None	Availability Impact:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 8 (kernel)	ELSA-2024-5101	2024-08-08
Oracle Linux version 9 (kernel)	ELSA-2024-9315	2024-11-14