"value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetrom: check buffer length before accessing it\n\nSyzkaller reports an uninit value read from ax25cmp when sending raw message\nthrough ieee802154 implementation.\n\n=====================================================\nBUG: KMSAN: uninit-value in ax25cmp+0x3a5/0x460 net/ax25/ax25_addr.c:119\n ax25cmp+0x3a5/0x460 net/ax25/ax25_addr.c:119\n nr_dev_get+0x20e/0x450 net/netrom/nr_route.c:601\n nr_route_frame+0x1a2/0xfc0 net/netrom/nr_route.c:774\n nr_xmit+0x5a/0x1c0 net/netrom/nr_dev.c:144\n __netdev_start_xmit include/linux/netdevice.h:4940 [inline]\n netdev_start_xmit include/linux/netdevice.h:4954 [inline]\n xmit_one net/core/dev.c:3548 [inline]\n dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3564\n __dev_queue_xmit+0x33b8/0x5130 net/core/dev.c:4349\n dev_queue_xmit include/linux/netdevice.h:3134 [inline]\n raw_sendmsg+0x654/0xc10 net/ieee802154/socket.c:299\n ieee802154_sock_sendmsg+0x91/0xc0 net/ieee802154/socket.c:96\n sock_sendmsg_nosec net/socket.c:730 [inline]\n __sock_sendmsg net/socket.c:745 [inline]\n ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584\n ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638\n __sys_sendmsg net/socket.c:2667 [inline]\n __do_sys_sendmsg net/socket.c:2676 [inline]\n __se_sys_sendmsg net/socket.c:2674 [inline]\n __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x63/0x6b\n\nUninit was created at:\n slab_post_alloc_hook+0x129/0xa70 mm/slab.h:768\n slab_alloc_node mm/slub.c:3478 [inline]\n kmem_cache_alloc_node+0x5e9/0xb10 mm/slub.c:3523\n kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:560\n __alloc_skb+0x318/0x740 net/core/skbuff.c:651\n alloc_skb include/linux/skbuff.h:1286 [inline]\n alloc_skb_with_frags+0xc8/0xbd0 net/core/skbuff.c:6334\n sock_alloc_send_pskb+0xa80/0xbf0 net/core/sock.c:2780\n sock_alloc_send_skb include/net/sock.h:1884 [inline]\n raw_sendmsg+0x36d/0xc10 net/ieee802154/socket.c:282\n ieee802154_sock_sendmsg+0x91/0xc0 net/ieee802154/socket.c:96\n sock_sendmsg_nosec net/socket.c:730 [inline]\n __sock_sendmsg net/socket.c:745 [inline]\n ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584\n ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638\n __sys_sendmsg net/socket.c:2667 [inline]\n __do_sys_sendmsg net/socket.c:2676 [inline]\n __se_sys_sendmsg net/socket.c:2674 [inline]\n __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x63/0x6b\n\nCPU: 0 PID: 5037 Comm: syz-executor166 Not tainted 6.7.0-rc7-syzkaller-00003-gfbafc3e621c3 #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023\n=====================================================\n\nThis issue occurs because the skb buffer is too small, and it's actual\nallocation is aligned. This hides an actual issue, which is that nr_route_frame\ndoes not validate the buffer size before using it.\n\nFix this issue by checking skb->len before accessing any fields in skb->data.\n\nFound by Linux Verification Center (linuxtesting.org) with Syzkaller."
},
{
"lang":"es",
"value":"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: netrom: comprobar la longitud del b\u00fafer antes de acceder a \u00e9l Syzkaller informa de un valor no inicializado le\u00eddo desde ax25cmp al enviar un mensaje sin formato a trav\u00e9s de la implementaci\u00f3n de ieee802154. ======================================================= ERROR: KMSAN: valor no inicializado en ax25cmp+0x3a5/0x460 net/ax25/ax25_addr.c:119 ax25cmp+0x3a5/0x460 net/ax25/ax25_addr.c:119 nr_dev_get+0x20e/0x450 net/netrom/nr_route.c:601 nr_route_frame+0x1a2/0xfc0 net/netrom/nr_route.c:774 nr_xmit+0x5a/0x1c0 net/netrom/nr_dev.c:144 __netdev_start_xmit include/linux/netdevice.h:4940 [en l\u00ednea] netdev_start_xmit include/linux/netdevice.h:4954 [en l\u00ednea] xmit_one net/core/dev.c:3548 [en l\u00ednea] dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3564 __dev_queue_xmit+0x33b8/0x5130 net/core/dev.c:4349 dev_queue_xmit include/linux/netdevice.h:3134 [en l\u00ednea] raw_sendmsg+0x654/0xc10 net/ieee802154/socket.c:299 ieee802154_sock_sendmsg+0x91/0xc0 net/ieee802154/socket.c:96 sock_sendmsg_nosec net/socket.c:730 [en l\u00ednea] __sock_sendmsg net/socket.c:745 [en l\u00ednea] ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638 __sys_sendmsg net/socket.c:2667 [en l\u00ednea] __do_sys_sendmsg net/socket.c:2676 [en l\u00ednea] __se_sys_sendmsg net/socket.c:2674 [en l\u00ednea] __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674 do_syscall_x64 arch/x86/entry/common.c:52 [en l\u00ednea] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Se cre\u00f3 un unit en: slab_post_alloc_hook+0x129/0xa70 mm/slab.h:768 slab_alloc_node mm/slub.c:3478 [en l\u00ednea] kmem_cache_alloc_node+0x5e9/0xb10 mm/slub.c:3523 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:560 __alloc_skb+0x318/0x740 net/core/skbuff.c:651 alloc_skb include/linux/skbuff.h:1286 [en l\u00ednea] alloc_skb_with_frags+0xc8/0xbd0 net/core/skbuff.c:6334 sock_alloc_send_pskb+0xa80/0xbf0 net/core/sock.c:2780 sock_alloc_send_skb include/net/sock.h:1884 [en l\u00ednea] raw_sendmsg+0x36d/0xc10 net/ieee802154/socket.c:282 ieee802154_sock_sendmsg+0x91/0xc0 net/ieee802154/socket.c:96 sock_sendmsg_nosec net/socket.c:730 [en l\u00ednea] __sock_sendmsg net/socket.c:745 [en l\u00ednea] ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638 __sys_sendmsg net/socket.c:2667 [en l\u00ednea] __do_sys_sendmsg net/socket.c:2676 [en l\u00ednea] __se_sys_sendmsg net/socket.c:2674 [en l\u00ednea] __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674 do_syscall_x64 arch/x86/entry/common.c:52 [en l\u00ednea] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b CPU: 0 PID: 5037 Comm: syz-executor166 No contaminado 6.7.0-rc7-syzkaller-00003-gfbafc3e621c3 #0 Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 17/11/2023 ======================================================= Este problema se produce porque el b\u00fafer skb es demasiado peque\u00f1o, y su asignaci\u00f3n actual est\u00e1 alineada. Esto oculta un problema real, que es que nr_route_frame no valida el tama\u00f1o del b\u00fafer antes de usarlo. Solucione este problema comprobando skb->len antes de acceder a cualquier campo en skb->data. Encontrado por Linux Verification Center (linuxtesting.org) con Syzkaller."
