CVSS: -EPSS: 0%CPEs: 4EXPL: 0CVE-2021-47452 – netfilter: nf_tables: skip netdev events generated on netns removal
https://notcve.org/view.php?id=CVE-2021-47452
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: skip netdev events generated on netns removal syzbot reported following (harmless) WARN: WARNING: CPU: 1 PID: 2648 at net/netfilter/core.c:468 nft_netdev_unregister_hooks net/netfilter/nf_tables_api.c:230 [inline] nf_tables_unregister_hook include/net/netfilter/nf_tables.h:1090 [inline] __nft_release_basechain+0x138/0x640 net/netfilter/nf_tables_api.c:9524 nft_netdev_event net/netfilter/nft_chain_filter.c:351 [inline] nf_tables_netdev_event+0x521/0x8a0 net/netfilter/nft_chain_filter.c:382 reproducer: unshare -n bash -c 'ip link add br0 type bridge; nft add table netdev t ; \ nft add chain netdev t ingress \{ type filter hook ingress device "br0" \ priority 0\; policy drop\; \}' Problem is that when netns device exit hooks create the UNREGISTER event, the .pre_exit hook for nf_tables core has already removed the base hook. Notifier attempts to do this again. The need to do base hook unregister unconditionally was needed in the past, because notifier was last stage where reg->dev dereference was safe. Now that nf_tables does the hook removal in .pre_exit, this isn't needed anymore. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: netfilter: nf_tables: omitir eventos de netdev generados al eliminar netns syzbot informó lo siguiente (inofensivo) ADVERTENCIA: ADVERTENCIA: CPU: 1 PID: 2648 en net/netfilter/core.c:468 nft_netdev_unregister_hooks net/netfilter/nf_tables_api.c:230 [en línea] nf_tables_unregister_hook include/net/netfilter/nf_tables.h:1090 [en línea] __nft_release_basechain+0x138/0x640 net/netfilter/nf_tables_api.c:9524 nft_netdev_event net/netfilter/nft_ filtro_cadena.c: 351 [en línea] nf_tables_netdev_event+0x521/0x8a0 net/netfilter/nft_chain_filter.c:382 reproductor: dejar de compartir -n bash -c 'ip link agregar puente tipo br0; nft agregar tabla netdev t; \ nft add chain netdev t ingress \{ tipo filtro gancho ingreso dispositivo "br0" \ prioridad 0\; caída de la política\; \}' El problema es que cuando los ganchos de salida del dispositivo netns crean el evento UNREGISTER, el gancho .pre_exit para nf_tables core ya ha eliminado el gancho base. Notifier intenta hacer esto nuevamente. La necesidad de cancelar el registro del enlace base incondicionalmente era necesaria en el pasado, porque el notificador era la última etapa donde la desreferencia reg->dev era segura. • https://git.kernel.org/stable/c/767d1216bff82507c945e92fe719dff2083bb2f4 https://git.kernel.org/stable/c/b110391d1e806167254d3c7ae5d637191d913175 https://git.kernel.org/stable/c/0a0e5d47670b753d3dbf88f3c77a97a30864d9bd https://git.kernel.org/stable/c/90c7c58aa2bd02c65a4c63b7dfe0b16eab12cf9f https://git.kernel.org/stable/c/68a3765c659f809dcaac20030853a054646eb739 •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47451 – netfilter: xt_IDLETIMER: fix panic that occurs when timer_type has garbage value
https://notcve.org/view.php?id=CVE-2021-47451
In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_IDLETIMER: fix panic that occurs when timer_type has garbage value Currently, when the rule related to IDLETIMER is added, idletimer_tg timer structure is initialized by kmalloc on executing idletimer_tg_create function. However, in this process timer->timer_type is not defined to a specific value. Thus, timer->timer_type has garbage value and it occurs kernel panic. So, this commit fixes the panic by initializing timer->timer_type using kzalloc instead of kmalloc. Test commands: # iptables -A OUTPUT -j IDLETIMER --timeout 1 --label test $ cat /sys/class/xt_idletimer/timers/test Killed Splat looks like: BUG: KASAN: user-memory-access in alarm_expires_remaining+0x49/0x70 Read of size 8 at addr 0000002e8c7bc4c8 by task cat/917 CPU: 12 PID: 917 Comm: cat Not tainted 5.14.0+ #3 79940a339f71eb14fc81aee1757a20d5bf13eb0e Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Call Trace: dump_stack_lvl+0x6e/0x9c kasan_report.cold+0x112/0x117 ? alarm_expires_remaining+0x49/0x70 __asan_load8+0x86/0xb0 alarm_expires_remaining+0x49/0x70 idletimer_tg_show+0xe5/0x19b [xt_IDLETIMER 11219304af9316a21bee5ba9d58f76a6b9bccc6d] dev_attr_show+0x3c/0x60 sysfs_kf_seq_show+0x11d/0x1f0 ? • https://git.kernel.org/stable/c/68983a354a655c35d3fb204489d383a2a051fda7 https://git.kernel.org/stable/c/2a670c323055282c9b72794a491d53cef86bbeaf https://git.kernel.org/stable/c/cae7cab804c943d723d52724a3aeb07a3f4a2650 https://git.kernel.org/stable/c/902c0b1887522a099aa4e1e6b4b476c2fe5dd13e •
CVSS: -EPSS: 0%CPEs: 2EXPL: 0CVE-2021-47448 – mptcp: fix possible stall on recvmsg()
https://notcve.org/view.php?id=CVE-2021-47448
In the Linux kernel, the following vulnerability has been resolved: mptcp: fix possible stall on recvmsg() recvmsg() can enter an infinite loop if the caller provides the MSG_WAITALL, the data present in the receive queue is not sufficient to fulfill the request, and no more data is received by the peer. When the above happens, mptcp_wait_data() will always return with no wait, as the MPTCP_DATA_READY flag checked by such function is set and never cleared in such code path. Leveraging the above syzbot was able to trigger an RCU stall: rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10499 ticks this GP) idle=0af/1/0x4000000000000000 softirq=10678/10678 fqs=1 (t=10500 jiffies g=13089 q=109) rcu: rcu_preempt kthread starved for 10497 jiffies! g13089 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:28696 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4955 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6236 schedule+0xd3/0x270 kernel/sched/core.c:6315 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8510 Comm: syz-executor827 Not tainted 5.15.0-rc2-next-20210920-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0xc8/0x180 mm/kasan/generic.c:189 Code: 38 00 74 ed 48 8d 50 08 eb 09 48 83 c0 01 48 39 d0 74 7a 80 38 00 74 f2 48 89 c2 b8 01 00 00 00 48 85 d2 75 56 5b 5d 41 5c c3 <48> 85 d2 74 5e 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 50 80 38 00 RSP: 0018:ffffc9000cd676c8 EFLAGS: 00000283 RAX: ffffed100e9a110e RBX: ffffed100e9a110f RCX: ffffffff88ea062a RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff888074d08870 RBP: ffffed100e9a110e R08: 0000000000000001 R09: ffff888074d08877 R10: ffffed100e9a110e R11: 0000000000000000 R12: ffff888074d08000 R13: ffff888074d08000 R14: ffff888074d08088 R15: ffff888074d08000 FS: 0000555556d8e300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 S: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000180 CR3: 0000000068909000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:101 [inline] test_and_clear_bit include/asm-generic/bitops/instrumented-atomic.h:83 [inline] mptcp_release_cb+0x14a/0x210 net/mptcp/protocol.c:3016 release_sock+0xb4/0x1b0 net/core/sock.c:3204 mptcp_wait_data net/mptcp/protocol.c:1770 [inline] mptcp_recvmsg+0xfd1/0x27b0 net/mptcp/protocol.c:2080 inet6_recvmsg+0x11b/0x5e0 net/ipv6/af_inet6.c:659 sock_recvmsg_nosec net/socket.c:944 [inline] ____sys_recvmsg+0x527/0x600 net/socket.c:2626 ___sys_recvmsg+0x127/0x200 net/socket.c:2670 do_recvmmsg+0x24d/0x6d0 net/socket.c:2764 __sys_recvmmsg net/socket.c:2843 [inline] __do_sys_recvmmsg net/socket.c:2866 [inline] __se_sys_recvmmsg net/socket.c:2859 [inline] __x64_sys_recvmmsg+0x20b/0x260 net/socket.c:2859 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: 0033:0x7fc200d2 ---truncated--- En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mptcp: corrige posible bloqueo en recvmsg() recvmsg() puede entrar en un bucle infinito si la persona que llama proporciona MSG_WAITALL, los datos presentes en la cola de recepción no son suficientes para cumplir con la solicitud y el par no recibe más datos. Cuando sucede lo anterior, mptcp_wait_data() siempre regresará sin espera, ya que el indicador MPTCP_DATA_READY verificado por dicha función se establece y nunca se borra en dicha ruta de código. Aprovechar el syzbot anterior fue capaz de desencadenar una parada de RCU: rcu: INFO: rcu_preempt parada autodetectada en la CPU rcu: 0-...! • https://git.kernel.org/stable/c/7a6a6cbc3e592e339ad23e4e8ede9a3f6160bda8 https://git.kernel.org/stable/c/1a4554e94f0deff9fc1dc5addf93fa579cc29711 https://git.kernel.org/stable/c/612f71d7328c14369924384ad2170aae2a6abd92 •
CVSS: -EPSS: 0%CPEs: 8EXPL: 0CVE-2021-47445 – drm/msm: Fix null pointer dereference on pointer edp
https://notcve.org/view.php?id=CVE-2021-47445
In the Linux kernel, the following vulnerability has been resolved: drm/msm: Fix null pointer dereference on pointer edp The initialization of pointer dev dereferences pointer edp before edp is null checked, so there is a potential null pointer deference issue. Fix this by only dereferencing edp after edp has been null checked. Addresses-Coverity: ("Dereference before null check") En el kernel de Linux, se resolvió la siguiente vulnerabilidad: drm/msm: corrige la desreferencia del puntero nulo en el puntero edp. La inicialización del puntero dev desreferencias del puntero edp antes de edp se marca como nula, por lo que existe un posible problema de deferencia del puntero nulo. Solucione este problema eliminando la referencia a edp únicamente después de que se haya marcado como nulo. Direcciones-Cobertura: ("Desreferencia antes de verificación nula") • https://git.kernel.org/stable/c/ab5b0107ccf3821a6837b0f2819270d6fa0b278f https://git.kernel.org/stable/c/f175b9a83e5c252d7c74acddc792840016caae0a https://git.kernel.org/stable/c/bacac7d26849c8e903ceb7466d9ce8dc3c2797eb https://git.kernel.org/stable/c/0cd063aa0a09822cc1620fc59a67fe2f9f6338ac https://git.kernel.org/stable/c/7f642b93710b6b1119bdff90be01e6b5a2a5d669 https://git.kernel.org/stable/c/f302be08e3de94db8863a0b2958b2bb3e8e998e6 https://git.kernel.org/stable/c/91a340768b012f5b910a203a805b97a345b3db37 https://git.kernel.org/stable/c/46c8ddede0273d1d132beefa9de8b8203 •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47444 – drm/edid: In connector_bad_edid() cap num_of_ext by num_blocks read
https://notcve.org/view.php?id=CVE-2021-47444
In the Linux kernel, the following vulnerability has been resolved: drm/edid: In connector_bad_edid() cap num_of_ext by num_blocks read In commit e11f5bd8228f ("drm: Add support for DP 1.4 Compliance edid corruption test") the function connector_bad_edid() started assuming that the memory for the EDID passed to it was big enough to hold `edid[0x7e] + 1` blocks of data (1 extra for the base block). It completely ignored the fact that the function was passed `num_blocks` which indicated how much memory had been allocated for the EDID. Let's fix this by adding a bounds check. This is important for handling the case where there's an error in the first block of the EDID. In that case we will call connector_bad_edid() without having re-allocated memory based on `edid[0x7e]`. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: drm/edid: En conector_bad_edid() cap num_of_ext por num_blocks leído En commit e11f5bd8228f ("drm: Agregar soporte para prueba de corrupción edid de cumplimiento de DP 1.4") la función conector_bad_edid() comenzó a asumir que la memoria para el EDID que se le pasó era lo suficientemente grande como para contener bloques de datos `edid[0x7e] + 1` (1 adicional para el bloque base). Ignoró por completo el hecho de que a la función se le pasó `num_blocks`, que indicaba cuánta memoria se había asignado para el EDID. • https://git.kernel.org/stable/c/e11f5bd8228fc3760c221f940b9f6365dbf3e7ed https://git.kernel.org/stable/c/a7b45024f66f9ec769e8dbb1a51ae83cd05929c7 https://git.kernel.org/stable/c/09f3946bb452918dbfb1982add56f9ffaae393dc https://git.kernel.org/stable/c/97794170b696856483f74b47bfb6049780d2d3a0 •