CVE-2021-47515 – seg6: fix the iif in the IPv6 socket control block
https://notcve.org/view.php?id=CVE-2021-47515
In the Linux kernel, the following vulnerability has been resolved: seg6: fix the iif in the IPv6 socket control block When an IPv4 packet is received, the ip_rcv_core(...) sets the receiving interface index into the IPv4 socket control block (v5.16-rc4, net/ipv4/ip_input.c line 510): IPCB(skb)->iif = skb->skb_iif; If that IPv4 packet is meant to be encapsulated in an outer IPv6+SRH header, the seg6_do_srh_encap(...) performs the required encapsulation. In this case, the seg6_do_srh_encap function clears the IPv6 socket control block (v5.16-rc4 net/ipv6/seg6_iptunnel.c line 163): memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); The memset(...) was introduced in commit ef489749aae5 ("ipv6: sr: clear IP6CB(skb) on SRH ip4ip6 encapsulation") a long time ago (2019-01-29). Since the IPv6 socket control block and the IPv4 socket control block share the same memory area (skb->cb), the receiving interface index info is lost (IP6CB(skb)->iif is set to zero). As a side effect, that condition triggers a NULL pointer dereference if commit 0857d6f8c759 ("ipv6: When forwarding count rx stats on the orig netdev") is applied. To fix that issue, we set the IP6CB(skb)->iif with the index of the receiving interface once again. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: seg6: corrige el iif en el bloque de control del socket IPv6 Cuando se recibe un paquete IPv4, ip_rcv_core(...) establece el índice de la interfaz de recepción en el bloque de control del socket IPv4 (v5 .16-rc4, net/ipv4/ip_input.c línea 510): IPCB(skb)->iif = skb->skb_iif; Si ese paquete IPv4 debe encapsularse en un encabezado IPv6+SRH externo, seg6_do_srh_encap(...) realiza la encapsulación requerida. En este caso, la función seg6_do_srh_encap borra el bloque de control del socket IPv6 (v5.16-rc4 net/ipv6/seg6_iptunnel.c línea 163): memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); El memset(...) se introdujo en El commit ef489749aae5 ("ipv6: sr: clear IP6CB(skb) en la encapsulación SRH ip4ip6") hace mucho tiempo (29 de enero de 2019). Dado que el bloque de control del socket IPv6 y el bloque de control del socket IPv4 comparten la misma área de memoria (skb->cb), la información del índice de la interfaz de recepción se pierde (IP6CB(skb)->iif se establece en cero). Como efecto secundario, esa condición desencadena una desreferencia del puntero NULL si se aplica el commit 0857d6f8c759 ("ipv6: al reenviar estadísticas de recuento de rx en el netdev original"). • https://git.kernel.org/stable/c/c630ec8bdadae9d557b1ceb9d6c06e149108a0d4 https://git.kernel.org/stable/c/2f704348c93ff8119e642dae6a72327f90b82810 https://git.kernel.org/stable/c/ef489749aae508e6f17886775c075f12ff919fb1 https://git.kernel.org/stable/c/b71b7e0280f47b4ac633fbfd153423814ea87810 https://git.kernel.org/stable/c/b16d412e5f79734033df04e97d7ea2f50a8e9fe3 https://git.kernel.org/stable/c/6431e71093f3da586a00c6d931481ffb0dc2db0e https://git.kernel.org/stable/c/ef8804e47c0a44ae106ead1740408af5ea6c6ee9 https://git.kernel.org/stable/c/666521b3852d2b2f52d570f9122b1e4b5 • CWE-476: NULL Pointer Dereference •
CVE-2021-47514 – devlink: fix netns refcount leak in devlink_nl_cmd_reload()
https://notcve.org/view.php?id=CVE-2021-47514
In the Linux kernel, the following vulnerability has been resolved: devlink: fix netns refcount leak in devlink_nl_cmd_reload() While preparing my patch series adding netns refcount tracking, I spotted bugs in devlink_nl_cmd_reload() Some error paths forgot to release a refcount on a netns. To fix this, we can reduce the scope of get_net()/put_net() section around the call to devlink_reload(). En el kernel de Linux, se resolvió la siguiente vulnerabilidad: devlink: corrige la fuga de refcount de netns en devlink_nl_cmd_reload() Mientras preparaba mi serie de parches agregando el seguimiento de refcount de netns, detecté errores en devlink_nl_cmd_reload() Algunas rutas de error olvidaron publicar un refcount en netns. Para solucionar este problema, podemos reducir el alcance de la sección get_net()/put_net() alrededor de la llamada a devlink_reload(). • https://git.kernel.org/stable/c/ccdf07219da6bd1f43c6ddcde4c0e36993c7365a https://git.kernel.org/stable/c/4b7e90672af8e0c78205db006f1b0a20ebd07f5f https://git.kernel.org/stable/c/fe30b70ca84da9c4aca85c03ad86e7a9b89c5ded https://git.kernel.org/stable/c/4dbb0dad8e63fcd0b5a117c2861d2abe7ff5f186 •
CVE-2021-47512 – net/sched: fq_pie: prevent dismantle issue
https://notcve.org/view.php?id=CVE-2021-47512
In the Linux kernel, the following vulnerability has been resolved: net/sched: fq_pie: prevent dismantle issue For some reason, fq_pie_destroy() did not copy working code from pie_destroy() and other qdiscs, thus causing elusive bug. Before calling del_timer_sync(&q->adapt_timer), we need to ensure timer will not rearm itself. rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (4416 ticks this GP) idle=60d/1/0x4000000000000000 softirq=10433/10434 fqs=2579 (t=10501 jiffies g=13085 q=3989) NMI backtrace for cpu 0 CPU: 0 PID: 13 Comm: ksoftirqd/0 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2597 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:write_comp_data kernel/kcov.c:221 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x1d/0x80 kernel/kcov.c:273 Code: 54 c8 20 48 89 10 c3 66 0f 1f 44 00 00 53 41 89 fb 41 89 f1 bf 03 00 00 00 65 48 8b 0c 25 40 70 02 00 48 89 ce 4c 8b 54 24 08 <e8> 4e f7 ff ff 84 c0 74 51 48 8b 81 88 15 00 00 44 8b 81 84 15 00 RSP: 0018:ffffc90000d27b28 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff888064bf1bf0 RCX: ffff888011928000 RDX: ffff888011928000 RSI: ffff888011928000 RDI: 0000000000000003 RBP: ffff888064bf1c28 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff875d8295 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8880783dd300 R14: 0000000000000000 R15: 0000000000000000 pie_calculate_probability+0x405/0x7c0 net/sched/sch_pie.c:418 fq_pie_timer+0x170/0x2a0 net/sched/sch_fq_pie.c:383 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 run_ksoftirqd kernel/softirq.c:921 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:913 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK> En el kernel de Linux, se resolvió la siguiente vulnerabilidad: net/sched: fq_pie: previene el problema de desmantelamiento Por alguna razón, fq_pie_destroy() no copió el código de trabajo de pie_destroy() y otras qdiscs, causando así un error difícil de alcanzar. Antes de llamar a del_timer_sync(&q->adapt_timer), debemos asegurarnos de que el temporizador no se rearme solo. rcu: INFO: rcu_preempt se bloqueó automáticamente en la CPU rcu: 0-....: (4416 ticks this GP) idle=60d/1/0x4000000000000000 softirq=10433/10434 fqs=2579 (t=10501 jiffies g=13085 q=3989) NMI backtrace for cpu 0 CPU: 0 PID: 13 Comm: ksoftirqd/0 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2597 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:write_comp_data kernel/kcov.c:221 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x1d/0x80 kernel/kcov.c:273 Code: 54 c8 20 48 89 10 c3 66 0f 1f 44 00 00 53 41 89 fb 41 89 f1 bf 03 00 00 00 65 48 8b 0c 25 40 70 02 00 48 89 ce 4c 8b 54 24 08 4e f7 ff ff 84 c0 74 51 48 8b 81 88 15 00 00 44 8b 81 84 15 00 RSP: 0018:ffffc90000d27b28 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff888064bf1bf0 RCX: ffff888011928000 RDX: ffff888011928000 RSI: ffff888011928000 RDI: 0000000000000003 RBP: ffff888064bf1c28 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff875d8295 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8880783dd300 R14: 0000000000000000 R15: 0000000000000000 pie_calculate_probability+0x405/0x7c0 net/sched/sch_pie.c:418 fq_pie_timer+0x170/0x2a0 net/sched/sch_fq_pie.c:383 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 run_ksoftirqd kernel/softirq.c:921 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:913 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 • https://git.kernel.org/stable/c/ec97ecf1ebe485a17cd8395a5f35e6b80b57665a https://git.kernel.org/stable/c/2a51edaf5cc563574878b93d7ef3d5955dda7030 https://git.kernel.org/stable/c/d86216dfda7c98375f809e26a30bfdaaba21d46e https://git.kernel.org/stable/c/61c2402665f1e10c5742033fce18392e369931d7 •
CVE-2021-47511 – ALSA: pcm: oss: Fix negative period/buffer sizes
https://notcve.org/view.php?id=CVE-2021-47511
In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: oss: Fix negative period/buffer sizes The period size calculation in OSS layer may receive a negative value as an error, but the code there assumes only the positive values and handle them with size_t. Due to that, a too big value may be passed to the lower layers. This patch changes the code to handle with ssize_t and adds the proper error checks appropriately. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ALSA: pcm: oss: corrige tamaños de período/búfer negativos El cálculo del tamaño del período en la capa OSS puede recibir un valor negativo como error, pero el código allí asume solo los valores positivos y manejarlos con size_t. Debido a esto, es posible que se pase un valor demasiado grande a las capas inferiores. Este parche cambia el código para manejar con ssize_t y agrega las comprobaciones de errores adecuadas. • https://git.kernel.org/stable/c/be8869d388593e57223ad39297c8e54be632f2f2 https://git.kernel.org/stable/c/502e1146873d870f87da3b8f93d6bf2de5f38d0c https://git.kernel.org/stable/c/8af815ab052eaf74addbbfb556d63ce2137c0e1b https://git.kernel.org/stable/c/f96c0959c1ee92adc911c10d6ec209af50105049 https://git.kernel.org/stable/c/f12c8a7515f641885677960af450082569a87243 https://git.kernel.org/stable/c/02b2b691b77cd7b951fa7b6c9d44d4e472cdc823 https://git.kernel.org/stable/c/00a860678098fcd9fa8db2b5fb9d2ddf4776d4cc https://git.kernel.org/stable/c/9d2479c960875ca1239bcb899f386970c •
CVE-2021-47509 – ALSA: pcm: oss: Limit the period size to 16MB
https://notcve.org/view.php?id=CVE-2021-47509
In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: oss: Limit the period size to 16MB Set the practical limit to the period size (the fragment shift in OSS) instead of a full 31bit; a too large value could lead to the exhaust of memory as we allocate temporary buffers of the period size, too. As of this patch, we set to 16MB limit, which should cover all use cases. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ALSA: pcm: oss: Limitar el tamaño del período a 16 MB Establezca el límite práctico para el tamaño del período (el desplazamiento de fragmentos en OSS) en lugar de 31 bits completos; un valor demasiado grande podría provocar el agotamiento de la memoria, ya que también asignamos búferes temporales del tamaño del período. A partir de este parche, establecimos un límite de 16 MB, que debería cubrir todos los casos de uso. • https://git.kernel.org/stable/c/d1bb703ad050de9095f10b2d3416c32921ac6bcc https://git.kernel.org/stable/c/b02a41eebcc36d4f07196780f2e165ca2c499257 https://git.kernel.org/stable/c/be55f306396cd62c6889286a7194fd8b53363aeb https://git.kernel.org/stable/c/2e54cf6794bf82a54aaefc78da13819aea9cd28a https://git.kernel.org/stable/c/76f19e4cbb548e28547f8c328aa0bfb3a10222d3 https://git.kernel.org/stable/c/ad45babf7886e7a212ee1d5eda9ef49f696db43c https://git.kernel.org/stable/c/35a3e511032146941085f87dd9fb5b82ea5c00a2 https://git.kernel.org/stable/c/8839c8c0f77ab8fc0463f4ab8b37fca3f •