CVSS: -EPSS: 0%CPEs: 5EXPL: 0CVE-2021-47598 – sch_cake: do not call cake_destroy() from cake_init()
https://notcve.org/view.php?id=CVE-2021-47598
In the Linux kernel, the following vulnerability has been resolved: sch_cake: do not call cake_destroy() from cake_init() qdiscs are not supposed to call their own destroy() method from init(), because core stack already does that. syzbot was able to trigger use after free: DEBUG_LOCKS_WARN_ON(lock->magic != lock) WARNING: CPU: 0 PID: 21902 at kernel/locking/mutex.c:586 __mutex_lock_common kernel/locking/mutex.c:586 [inline] WARNING: CPU: 0 PID: 21902 at kernel/locking/mutex.c:586 __mutex_lock+0x9ec/0x12f0 kernel/locking/mutex.c:740 Modules linked in: CPU: 0 PID: 21902 Comm: syz-executor189 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:586 [inline] RIP: 0010:__mutex_lock+0x9ec/0x12f0 kernel/locking/mutex.c:740 Code: 08 84 d2 0f 85 19 08 00 00 8b 05 97 38 4b 04 85 c0 0f 85 27 f7 ff ff 48 c7 c6 20 00 ac 89 48 c7 c7 a0 fe ab 89 e8 bf 76 ba ff <0f> 0b e9 0d f7 ff ff 48 8b 44 24 40 48 8d b8 c8 08 00 00 48 89 f8 RSP: 0018:ffffc9000627f290 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88802315d700 RSI: ffffffff815f1db8 RDI: fffff52000c4fe44 RBP: ffff88818f28e000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815ebb5e R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffc9000627f458 R15: 0000000093c30000 FS: 0000555556abc400(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fda689c3303 CR3: 000000001cfbb000 CR4: 0000000000350ef0 Call Trace: <TASK> tcf_chain0_head_change_cb_del+0x2e/0x3d0 net/sched/cls_api.c:810 tcf_block_put_ext net/sched/cls_api.c:1381 [inline] tcf_block_put_ext net/sched/cls_api.c:1376 [inline] tcf_block_put+0xbc/0x130 net/sched/cls_api.c:1394 cake_destroy+0x3f/0x80 net/sched/sch_cake.c:2695 qdisc_create.constprop.0+0x9da/0x10f0 net/sched/sch_api.c:1293 tc_modify_qdisc+0x4c5/0x1980 net/sched/sch_api.c:1660 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5571 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2496 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f1bb06badb9 Code: Unable to access opcode bytes at RIP 0x7f1bb06bad8f. RSP: 002b:00007fff3012a658 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f1bb06badb9 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000003 R10: 0000000000000003 R11: 0000000000000246 R12: 00007fff3012a688 R13: 00007fff3012a6a0 R14: 00007fff3012a6e0 R15: 00000000000013c2 </TASK> En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: sch_cake: no llamar a cake_destroy() desde cake_init() Se supone que las qdiscs no deben llamar a su propio método destroy() desde init(), porque la pila central ya lo hace. syzbot pudo activar el use-after-free: DEBUG_LOCKS_WARN_ON(lock->magic != lock) ADVERTENCIA: CPU: 0 PID: 21902 en kernel/locking/mutex.c:586 __mutex_lock_common kernel/locking/mutex.c:586 [en línea] ADVERTENCIA: CPU: 0 PID: 21902 en kernel/locking/mutex.c:586 __mutex_lock+0x9ec/0x12f0 kernel/locking/mutex.c:740 Módulos vinculados en: CPU: 0 PID: 21902 Comm: syz-executor189 No contaminado 5.16 .0-rc4-syzkaller #0 Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:586 [en línea] RIP: 0010:__mutex_lock+ 0x9ec/0x12f0 kernel/locking/mutex.c:740 Código: 08 84 d2 0f 85 19 08 00 00 8b 05 97 38 4b 04 85 c0 0f 85 27 f7 ff ff 48 c7 c6 20 00 ac 89 48 c7 c7 a0 fe ab 89 e8 bf 76 ba ff <0f> 0b e9 0d f7 ff ff 48 8b 44 24 40 48 8d b8 c8 08 00 00 48 89 f8 RSP: 0018:ffffc9000627f290 EFLAGS: 00010282 RAX: 0000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88802315d700 RSI: ffffffff815f1db8 RDI: fffff52000c4fe44 RBP: ffff88818f28e000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815ebb5e R11: 00000 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffc9000627f458 R15: 0000000093c30000 FS: 000055556abc400(0000) GS:ffff8880b9c0000 0(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fda689c3303 CR3: 000000001cfbb000 CR4: 0000000000350ef0 Seguimiento de llamadas: tcf_chain0_head_change_cb_del+0x2e/0 x3d0 net/sched/cls_api.c:810 tcf_block_put_ext net/sched/cls_api.c:1381 [ en línea] tcf_block_put_ext net/sched/cls_api.c:1376 [en línea] tcf_block_put+0xbc/0x130 net/sched/cls_api.c:1394 cake_destroy+0x3f/0x80 net/sched/sch_cake.c:2695 qdisc_create.constprop.0+0x9da /0x10f0 net/sched/sch_api.c:1293 tc_modify_qdisc+0x4c5/0x1980 net/sched/sch_api.c:1660 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5571 netlink_rcv_skb+0x153/0x420 net/netlink/ af_netlink. c:2496 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [en línea] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c :704 [en línea] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463 __sys_sendmsg+0xe5/0x1b 0 red/toma. c:2492 do_syscall_x64 arch/x86/entry/common.c:50 [en línea] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 Entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f1bb06badb9 Código: No se puede acceder al código de operación bytes en RIP 0x7f1bb06bad8f. RSP: 002b:00007fff3012a658 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000000000003 RCX: 00007f1bb06badb9 RDX: 000000000 RSI: 00000000200007c0 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000003 R10: 00000003 R11: 0000000000000246 R12: 00007fff3012a688 R13: 00007fff3012a6a0 R14: 00007fff3012a6e0 R15: 00000000000013c2 • https://git.kernel.org/stable/c/046f6fd5daefac7f5abdafb436b30f63bc7c602b https://git.kernel.org/stable/c/4e388232e630ebe4f94b4a0715ec98c0e2b314a3 https://git.kernel.org/stable/c/0d80462fbdcafd536dcad7569e65d3d14a7e9f2f https://git.kernel.org/stable/c/20ad1ef02f9ad5e1dda9eeb113e4c158b4806986 https://git.kernel.org/stable/c/f6deae2e2d83bd267e1986f5d71d8c458e18fd99 https://git.kernel.org/stable/c/ab443c53916730862cec202078d36fd4008bea79 •
CVSS: -EPSS: 0%CPEs: 4EXPL: 0CVE-2021-47597 – inet_diag: fix kernel-infoleak for UDP sockets
https://notcve.org/view.php?id=CVE-2021-47597
In the Linux kernel, the following vulnerability has been resolved: inet_diag: fix kernel-infoleak for UDP sockets KMSAN reported a kernel-infoleak [1], that can exploited by unpriv users. After analysis it turned out UDP was not initializing r->idiag_expires. Other users of inet_sk_diag_fill() might make the same mistake in the future, so fix this in inet_sk_diag_fill(). [1] BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:121 [inline] BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:156 [inline] BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x69d/0x25c0 lib/iov_iter.c:670 instrument_copy_to_user include/linux/instrumented.h:121 [inline] copyout lib/iov_iter.c:156 [inline] _copy_to_iter+0x69d/0x25c0 lib/iov_iter.c:670 copy_to_iter include/linux/uio.h:155 [inline] simple_copy_to_iter+0xf3/0x140 net/core/datagram.c:519 __skb_datagram_iter+0x2cb/0x1280 net/core/datagram.c:425 skb_copy_datagram_iter+0xdc/0x270 net/core/datagram.c:533 skb_copy_datagram_msg include/linux/skbuff.h:3657 [inline] netlink_recvmsg+0x660/0x1c60 net/netlink/af_netlink.c:1974 sock_recvmsg_nosec net/socket.c:944 [inline] sock_recvmsg net/socket.c:962 [inline] sock_read_iter+0x5a9/0x630 net/socket.c:1035 call_read_iter include/linux/fs.h:2156 [inline] new_sync_read fs/read_write.c:400 [inline] vfs_read+0x1631/0x1980 fs/read_write.c:481 ksys_read+0x28c/0x520 fs/read_write.c:619 __do_sys_read fs/read_write.c:629 [inline] __se_sys_read fs/read_write.c:627 [inline] __x64_sys_read+0xdb/0x120 fs/read_write.c:627 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae Uninit was created at: slab_post_alloc_hook mm/slab.h:524 [inline] slab_alloc_node mm/slub.c:3251 [inline] __kmalloc_node_track_caller+0xe0c/0x1510 mm/slub.c:4974 kmalloc_reserve net/core/skbuff.c:354 [inline] __alloc_skb+0x545/0xf90 net/core/skbuff.c:426 alloc_skb include/linux/skbuff.h:1126 [inline] netlink_dump+0x3d5/0x16a0 net/netlink/af_netlink.c:2245 __netlink_dump_start+0xd1c/0xee0 net/netlink/af_netlink.c:2370 netlink_dump_start include/linux/netlink.h:254 [inline] inet_diag_handler_cmd+0x2e7/0x400 net/ipv4/inet_diag.c:1343 sock_diag_rcv_msg+0x24a/0x620 netlink_rcv_skb+0x447/0x800 net/netlink/af_netlink.c:2491 sock_diag_rcv+0x63/0x80 net/core/sock_diag.c:276 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x1095/0x1360 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x16f3/0x1870 net/netlink/af_netlink.c:1916 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg net/socket.c:724 [inline] sock_write_iter+0x594/0x690 net/socket.c:1057 do_iter_readv_writev+0xa7f/0xc70 do_iter_write+0x52c/0x1500 fs/read_write.c:851 vfs_writev fs/read_write.c:924 [inline] do_writev+0x63f/0xe30 fs/read_write.c:967 __do_sys_writev fs/read_write.c:1040 [inline] __se_sys_writev fs/read_write.c:1037 [inline] __x64_sys_writev+0xe5/0x120 fs/read_write.c:1037 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae Bytes 68-71 of 312 are uninitialized Memory access of size 312 starts at ffff88812ab54000 Data copied to user address 0000000020001440 CPU: 1 PID: 6365 Comm: syz-executor801 Not tainted 5.16.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 En el kernel de Linux, se resolvió la siguiente vulnerabilidad: inet_diag: corrige la fuga de información del kernel para sockets UDP KMSAN informó una fuga de información del kernel [1], que puede ser explotada por usuarios sin privilegios. Después del análisis resultó que UDP no estaba inicializando r->idiag_expires. Otros usuarios de inet_sk_diag_fill() podrían cometer el mismo error en el futuro, así que solucione este problema en inet_sk_diag_fill(). [1] ERROR: KMSAN: kernel-infoleak en instrument_copy_to_user include/linux/instrumented.h:121 [en línea] ERROR: KMSAN: kernel-infoleak en copia lib/iov_iter.c:156 [en línea] ERROR: KMSAN: kernel-infoleak en _copy_to_iter+0x69d/0x25c0 lib/iov_iter.c:670 instrument_copy_to_user include/linux/instrumented.h:121 [en línea] copia lib/iov_iter.c:156 [en línea] _copy_to_iter+0x69d/0x25c0 lib/iov_iter.c:670 copy_to_iter include/linux/uio.h:155 [en línea] simple_copy_to_iter+0xf3/0x140 net/core/datagram.c:519 __skb_datagram_iter+0x2cb/0x1280 net/core/datagram.c:425 skb_copy_datagram_iter+0xdc/0x270 net/core/datagram .c:533 skb_copy_datagram_msg include/linux/skbuff.h:3657 [en línea] netlink_recvmsg+0x660/0x1c60 net/netlink/af_netlink.c:1974 sock_recvmsg_nosec net/socket.c:944 [en línea] sock_recvmsg net/socket.c:962 [en línea] sock_read_iter+0x5a9/0x630 net/socket.c:1035 call_read_iter include/linux/fs.h:2156 [en línea] new_sync_read fs/read_write.c:400 [en línea] vfs_read+0x1631/0x1980 fs/read_write.c: 481 ksys_read+0x28c/0x520 fs/read_write.c:619 __do_sys_read fs/read_write.c:629 [en línea] __se_sys_read fs/read_write.c:627 [en línea] __x64_sys_read+0xdb/0x120 fs/read_write.c:627 _arco x64/ x86/entry/common.c:51 [en línea] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 Entry_SYSCALL_64_after_hwframe+0x44/0xae Uninit se creó en: slab_post_alloc_hook mm/slab.h:524 [en línea] slab_alloc_node mm/slub.c:3251 [en línea] __kmalloc_node_track_caller+0xe0c/0x1510 mm/slub.c:4974 kmalloc_reserve net/core/skbuff.c:354 [en línea] __alloc_skb+0x545/0xf90 net/core/skbuff.c:426 alloc_skb include/linux/skbuff.h:1126 [en línea] netlink_dump+0x3d5/0x16a0 net/netlink/af_netlink.c:2245 __netlink_dump_start+0xd1c/0xee0 net/netlink/af_netlink.c:2370 netlink_dump_start include/linux/netlink.h:254 [en línea] inet_diag_handler_cmd+0x2e7/0x400 net/ipv4/inet_diag.c:1343 sock_diag_rcv_msg+0x24a/0x620 netlink_rcv_skb+0x447/0x800 net/netlink/af_netlink.c:2491 sock_diag_rcv+0x63/0x80 net/core/sock_diag.c:276 netlink_unicast_kernel net/netlink/af_netlink.c: 1319 [en línea] netlink_unicast+0x1095/0x1360 netLink/af_netlink.c: 1345 netlink_sendmsg+0x16f3/0x1870 net/netlink/af_etlink.c: 1916 sockm. C: 704 [ en línea] sock_sendmsg net/socket.c:724 [en línea] sock_write_iter+0x594/0x690 net/socket.c:1057 do_iter_readv_writev+0xa7f/0xc70 do_iter_write+0x52c/0x1500 fs/read_write.c:851 vfs_writev fs/read_write.c:9 24 [en línea] do_writev+0x63f/0xe30 fs/read_write.c:967 __do_sys_writev fs/read_write.c:1040 [en línea] __se_sys_writev fs/read_write.c:1037 [en línea] __x64_sys_writev+0xe5/0x120 fs/read_write.c:1037 _syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 Entry_SYSCALL_64_after_hwframe+0x44/0xae Los bytes 68-71 de 312 no están inicializados El acceso a la memoria de tamaño 312 comienza en ffff88812ab54000 Datos copiados a la dirección de usuario 0000000020001440 CPU: 1 PID: 6365 Comm: syz-executor801 Not tainted 5.16.0-rc3-syzkaller #0 Nombre de hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 • https://git.kernel.org/stable/c/3c4d05c8056724aff3abc20650807dd828fded54 https://git.kernel.org/stable/c/7b5596e531253ce84213d9daa7120b71c9d83198 https://git.kernel.org/stable/c/3a4f6dba1eb98101abc012ef968a8b10dac1ce50 https://git.kernel.org/stable/c/e5d28205bf1de7082d904ed277ceb2db2879e302 https://git.kernel.org/stable/c/71ddeac8cd1d217744a0e060ff520e147c9328d1 •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47593 – mptcp: clear 'kern' flag from fallback sockets
https://notcve.org/view.php?id=CVE-2021-47593
In the Linux kernel, the following vulnerability has been resolved: mptcp: clear 'kern' flag from fallback sockets The mptcp ULP extension relies on sk->sk_sock_kern being set correctly: It prevents setsockopt(fd, IPPROTO_TCP, TCP_ULP, "mptcp", 6); from working for plain tcp sockets (any userspace-exposed socket). But in case of fallback, accept() can return a plain tcp sk. In such case, sk is still tagged as 'kernel' and setsockopt will work. This will crash the kernel, The subflow extension has a NULL ctx->conn mptcp socket: BUG: KASAN: null-ptr-deref in subflow_data_ready+0x181/0x2b0 Call Trace: tcp_data_ready+0xf8/0x370 [..] En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mptcp: borrar el indicador 'kern' de los sockets de reserva La extensión mptcp ULP depende de que sk->sk_sock_kern esté configurado correctamente: impide que setsockopt(fd, IPPROTO_TCP, TCP_ULP, "mptcp", 6); de funcionar para sockets tcp simples (cualquier socket expuesto al espacio de usuario). Pero en caso de respaldo, aceptar() puede devolver un sk tcp simple. En tal caso, sk todavía está etiquetado como 'kernel' y setsockopt funcionará. Esto bloqueará el kernel. • https://git.kernel.org/stable/c/cf7da0d66cc1a2a19fc5930bb746ffbb2d4cd1be https://git.kernel.org/stable/c/451f1eded7f56e93aaf52eb547ba97742d9c0e97 https://git.kernel.org/stable/c/c26ac0ea3a91c210cf90452e625dc441adf3e549 https://git.kernel.org/stable/c/d6692b3b97bdc165d150f4c1505751a323a80717 •
CVSS: -EPSS: 0%CPEs: 8EXPL: 0CVE-2021-47589 – igbvf: fix double free in `igbvf_probe`
https://notcve.org/view.php?id=CVE-2021-47589
In the Linux kernel, the following vulnerability has been resolved: igbvf: fix double free in `igbvf_probe` In `igbvf_probe`, if register_netdev() fails, the program will go to label err_hw_init, and then to label err_ioremap. In free_netdev() which is just below label err_ioremap, there is `list_for_each_entry_safe` and `netif_napi_del` which aims to delete all entries in `dev->napi_list`. The program has added an entry `adapter->rx_ring->napi` which is added by `netif_napi_add` in igbvf_alloc_queues(). However, adapter->rx_ring has been freed below label err_hw_init. So this a UAF. In terms of how to patch the problem, we can refer to igbvf_remove() and delete the entry before `adapter->rx_ring`. The KASAN logs are as follows: [ 35.126075] BUG: KASAN: use-after-free in free_netdev+0x1fd/0x450 [ 35.127170] Read of size 8 at addr ffff88810126d990 by task modprobe/366 [ 35.128360] [ 35.128643] CPU: 1 PID: 366 Comm: modprobe Not tainted 5.15.0-rc2+ #14 [ 35.129789] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [ 35.131749] Call Trace: [ 35.132199] dump_stack_lvl+0x59/0x7b [ 35.132865] print_address_description+0x7c/0x3b0 [ 35.133707] ? free_netdev+0x1fd/0x450 [ 35.134378] __kasan_report+0x160/0x1c0 [ 35.135063] ? • https://git.kernel.org/stable/c/d4e0fe01a38a073568aee541a0247fe734095979 https://git.kernel.org/stable/c/ffe1695b678729edec04037e691007900a2b2beb https://git.kernel.org/stable/c/79d9b092035dcdbe636b70433149df9cc6db1e49 https://git.kernel.org/stable/c/8d0c927a9fb2b4065230936b77b54f857a3754fc https://git.kernel.org/stable/c/cc9b655bb84f1be283293dfea94dff9a31b106ac https://git.kernel.org/stable/c/8addba6cab94ce01686ea2e80ed1530f9dc33a9a https://git.kernel.org/stable/c/74a16e062b23332d8db017ff4a41e16279c44411 https://git.kernel.org/stable/c/944b8be08131f5faf2cd2440aa1c24a39 •
CVSS: -EPSS: 0%CPEs: 7EXPL: 0CVE-2021-47588 – sit: do not call ipip6_dev_free() from sit_init_net()
https://notcve.org/view.php?id=CVE-2021-47588
In the Linux kernel, the following vulnerability has been resolved: sit: do not call ipip6_dev_free() from sit_init_net() ipip6_dev_free is sit dev->priv_destructor, already called by register_netdevice() if something goes wrong. Alternative would be to make ipip6_dev_free() robust against multiple invocations, but other drivers do not implement this strategy. syzbot reported: dst_release underflow WARNING: CPU: 0 PID: 5059 at net/core/dst.c:173 dst_release+0xd8/0xe0 net/core/dst.c:173 Modules linked in: CPU: 1 PID: 5059 Comm: syz-executor.4 Not tainted 5.16.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:dst_release+0xd8/0xe0 net/core/dst.c:173 Code: 4c 89 f2 89 d9 31 c0 5b 41 5e 5d e9 da d5 44 f9 e8 1d 90 5f f9 c6 05 87 48 c6 05 01 48 c7 c7 80 44 99 8b 31 c0 e8 e8 67 29 f9 <0f> 0b eb 85 0f 1f 40 00 53 48 89 fb e8 f7 8f 5f f9 48 83 c3 a8 48 RSP: 0018:ffffc9000aa5faa0 EFLAGS: 00010246 RAX: d6894a925dd15a00 RBX: 00000000ffffffff RCX: 0000000000040000 RDX: ffffc90005e19000 RSI: 000000000003ffff RDI: 0000000000040000 RBP: 0000000000000000 R08: ffffffff816a1f42 R09: ffffed1017344f2c R10: ffffed1017344f2c R11: 0000000000000000 R12: 0000607f462b1358 R13: 1ffffffff1bfd305 R14: ffffe8ffffcb1358 R15: dffffc0000000000 FS: 00007f66c71a2700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f88aaed5058 CR3: 0000000023e0f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> dst_cache_destroy+0x107/0x1e0 net/core/dst_cache.c:160 ipip6_dev_free net/ipv6/sit.c:1414 [inline] sit_init_net+0x229/0x550 net/ipv6/sit.c:1936 ops_init+0x313/0x430 net/core/net_namespace.c:140 setup_net+0x35b/0x9d0 net/core/net_namespace.c:326 copy_net_ns+0x359/0x5c0 net/core/net_namespace.c:470 create_new_namespaces+0x4ce/0xa00 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11e/0x180 kernel/nsproxy.c:226 ksys_unshare+0x57d/0xb50 kernel/fork.c:3075 __do_sys_unshare kernel/fork.c:3146 [inline] __se_sys_unshare kernel/fork.c:3144 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3144 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f66c882ce99 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f66c71a2168 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f66c893ff60 RCX: 00007f66c882ce99 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000048040200 RBP: 00007f66c8886ff1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff6634832f R14: 00007f66c71a2300 R15: 0000000000022000 </TASK> En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: sit: no llame a ipip6_dev_free() desde sit_init_net() ipip6_dev_free es sit dev->priv_destructor, ya llamado por Register_netdevice() si algo sale mal. La alternativa sería hacer que ipip6_dev_free() sea robusto contra múltiples invocaciones, pero otros controladores no implementan esta estrategia. syzbot informó: dst_release underflow ADVERTENCIA: CPU: 0 PID: 5059 en net/core/dst.c:173 dst_release+0xd8/0xe0 net/core/dst.c:173 Módulos vinculados en: CPU: 1 PID: 5059 Comm: syz -executor.4 Not tainted 5.16.0-rc5-syzkaller #0 Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:dst_release+0xd8/0xe0 net/core/dst.c :173 Código: 4c 89 f2 89 d9 31 c0 5b 41 5e 5d e9 da d5 44 f9 e8 1d 90 5f f9 c6 05 87 48 c6 05 01 48 c7 c7 80 44 99 8b 31 c0 e8 e8 67 29 f9 <0f> 0b eb 85 0f 1f 40 00 53 48 89 fb e8 f7 8f 5f f9 48 83 c3 a8 48 RSP: 0018:ffffc9000aa5faa0 EFLAGS: 00010246 RAX: d6894a925dd15a00 RBX: RCX: 0000000000040000 RDX: ffffc90005e19000 RSI: 000000000003ffff RDI: 0000000000040000 RBP: 0000000000000000 R08 : ffffffff816a1f42 R09: ffffed1017344f2c R10: ffffed1017344f2c R11: 0000000000000000 R12: 0000607f462b1358 R13: 1ffffffff1bfd305 R14: ffffe8ffffcb135 8 R15: dffffc0000000000 FS: 00007f66c71a2700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 50033 CR2: 00007f88aaed5058 CR3: 0000000023e0f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 00000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Seguimiento de llamadas: dst_cache_destroy+0x107/0x1e0 net/core/dst_cache.c:160 ipip6_dev_free net/ ipv6/sit.c:1414 [en línea] sit_init_net+0x229/0x550 net/ipv6/sit.c:1936 ops_init+0x313/0x430 net/core/net_namespace.c:140 setup_net+0x35b/0x9d0 net/core/net_namespace.c :326 copy_net_ns+0x359/0x5c0 net/core/net_namespace.c:470 create_new_namespaces+0x4ce/0xa00 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11e/0x180 kernel/nsproxy.c:226 ksys_unshare+0x57d/0xb50 .c :3075 __do_sys_unshare kernel/fork.c:3146 [en línea] __se_sys_unshare kernel/fork.c:3144 [en línea] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3144 do_syscall_x64 arch/x86/entry/common.c:50 [en línea ] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 Entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f66c882ce99 Código: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP:00 007f66c71a2168 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f66c893ff60 RCX: 00007f66c882ce99 RDX: 0000000000000000 RSI: 0000000000 000000 RDI: 0000000048040200 RBP: 00007f66c8886ff1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 00000000000 00246 R12: 0000000000000000 R13: 00007fff6634832f R14: 00007f66c71a2300 R15: 0000000000022000 • https://git.kernel.org/stable/c/cf124db566e6b036b8bcbe8decbed740bdfac8c6 https://git.kernel.org/stable/c/95876855a55072572895a236b156ffb357fd5538 https://git.kernel.org/stable/c/4e1797914d8f223726ff6ae5ece4f97d73f21bab https://git.kernel.org/stable/c/e56b65c1e74d7f706d74b51baba15187be2fb4b5 https://git.kernel.org/stable/c/ad0ed314d6167b212939e3839428ba0c8bb16adb https://git.kernel.org/stable/c/6f46c59e60b64620d5d386c8ee2eaa11ebe3b595 https://git.kernel.org/stable/c/44a6c846bc3a7efe7d394bab8b2ae3b7f580e190 https://git.kernel.org/stable/c/e28587cc491ef0f3c51258fdc87fbc386 •