"value":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: Fix uninit-value access in __ip_make_skb()\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->flowi4_flags instead of testing HDRINCL\non the socket.\n\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.\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"
"value":"En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: ipv4: corrigi\u00f3 el acceso de valor uninit en __ip_make_skb() KMSAN inform\u00f3 el acceso de valor uninit en __ip_make_skb() [1]. __ip_make_skb() prueba HDRINCL para saber si el skb tiene icmphdr. Sin embargo, HDRINCL puede provocar una condici\u00f3n de ejecuci\u00f3n. Si llamar a setsockopt(2) con IP_HDRINCL cambia HDRINCL mientras se ejecuta __ip_make_skb(), la funci\u00f3n acceder\u00e1 a icmphdr en el skb incluso si no est\u00e1 incluido. Esto provoca el problema informado por KMSAN. Verifique FLOWI_FLAG_KNOWN_NH en fl4->flowi4_flags en lugar de probar HDRINCL en el socket. Adem\u00e1s, fl4->fl4_icmp_type y fl4->fl4_icmp_code no est\u00e1n inicializados. Estas son una uni\u00f3n en la estructura flowi4 y se inicializan impl\u00edcitamente mediante flowi4_init_output(), pero no debemos confiar en un dise\u00f1o de uni\u00f3n espec\u00edfico. Inicial\u00edcelos expl\u00edcitamente en raw_sendmsg(). [1] ERROR: KMSAN: valor uninit en __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481 __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481 ip_finish_skb include/net/ip.h:243 [ inline] ip_push_pending_frames+0x4c/0x5c0 net/ipv4/ip_output.c:1508 raw_sendmsg+0x2381/0x2690 net/ipv4/raw.c:654 inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851 net/socket.c : 730 [en l\u00ednea] __sock_sendmsg+0x274/0x3c0 net/Socket.c: 745 __sys_sendto+0x62c/0x7b0 net/Socket.c: 2191 __do_sys_sendto net/socket.c: 2203 [en l\u00ednea] __se_sys_sendto net/sows. ] __x64_sys_sendto+0x130/0x200 net/socket.c:2199 do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83 Entry_SYSCALL_64_after_hwframe+0x6d/0x75 Uninit se cre\u00f3 en: slab_post_alloc_hook mm/slub.c :3804 [en l\u00ednea] slab_alloc_node mm/slub.c:3845 [en l\u00ednea] kmem_cache_alloc_node+0x5f6/0xc50 mm/slub.c:3888 kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:577 __alloc_skb+0x35a/0x7c0 net/core/skbuff.c: 668 alloc_skb include/linux/skbuff.h:1318 [en l\u00ednea] __ip_append_data+0x49ab/0x68c0 net/ipv4/ip_output.c:1128 ip_append_data+0x1e7/0x260 net/ipv4/ip_output.c:1365 raw_sendmsg+0x22b1/0x2690 net /ipv4 /raw.c:648 inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:730 [en l\u00ednea] __sock_sendmsg+0x274/0x3c0 net/socket.c:745 __sys_sendto+0x62c/0x7b0 net / socket.c:2191 __do_sys_sendto net/socket.c:2203 [en l\u00ednea] __se_sys_sendto net/socket.c:2199 [en l\u00ednea] __x64_sys_sendto+0x130/0x200 net/socket.c:2199 do_syscall_64+0xd8/0x1f0 arch/x86/ent ry/ common.c:83 Entry_SYSCALL_64_after_hwframe+0x6d/0x75 CPU: 1 PID: 15709 Comm: syz-executor.7 Not tainted 6.8.0-11567-gb3603fcb79b1 #25 Nombre de hardware: PC est\u00e1ndar QEMU (i440FX + PIIX, 1996), BIOS 1.16 .3-1.fc39 01/04/2014"
