CVSS: 5.5EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47559 – net/smc: Fix NULL pointer dereferencing in smc_vlan_by_tcpsk()
https://notcve.org/view.php?id=CVE-2021-47559
In the Linux kernel, the following vulnerability has been resolved: net/smc: Fix NULL pointer dereferencing in smc_vlan_by_tcpsk() Coverity reports a possible NULL dereferencing problem: in smc_vlan_by_tcpsk(): 6. returned_null: netdev_lower_get_next returns NULL (checked 29 out of 30 times). 7. var_assigned: Assigning: ndev = NULL return value from netdev_lower_get_next. 1623 ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower); CID 1468509 (#1 of 1): Dereference null return value (NULL_RETURNS) 8. dereference: Dereferencing a pointer that might be NULL ndev when calling is_vlan_dev. 1624 if (is_vlan_dev(ndev)) { Remove the manual implementation and use netdev_walk_all_lower_dev() to iterate over the lower devices. While on it remove an obsolete function parameter comment. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net/smc: corrige la desreferenciación del puntero NULL en smc_vlan_by_tcpsk() Coverity informa un posible problema de desreferenciación de NULL: en smc_vlan_by_tcpsk(): 6. return_null: netdev_lower_get_next devuelve NULL (comprobado 29 de 30 veces). 7. var_assigned: Asignación: ndev = valor de retorno NULL de netdev_lower_get_next. 1623 ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower); CID 1468509 (#1 de 1): Desreferenciar valor de retorno nulo (NULL_RETURNS) 8. desreferencia: Desreferenciar un puntero que podría ser NULL ndev al llamar a is_vlan_dev. 1624 if (is_vlan_dev(ndev)) { Elimine la implementación manual y use netdev_walk_all_lower_dev() para iterar sobre los dispositivos inferiores. Mientras esté en él, elimine un comentario de parámetro de función obsoleto. A vulnerability was found in the Linux kernel's SMC implementation in the smc_vlan_by_tcpsk() function. • https://git.kernel.org/stable/c/cb9d43f6775457cac75544bc4197f26ac2b6f294 https://git.kernel.org/stable/c/c94cbd262b6aa3b54d73a1ed1f9c0d19df57f4ff https://git.kernel.org/stable/c/bb851d0fb02547d03cd40106b5f2391c4fed6ed1 https://git.kernel.org/stable/c/587acad41f1bc48e16f42bb2aca63bf323380be8 https://access.redhat.com/security/cve/CVE-2021-47559 https://bugzilla.redhat.com/show_bug.cgi?id=2283390 • CWE-476: NULL Pointer Dereference •
CVSS: -EPSS: 0%CPEs: 2EXPL: 0CVE-2021-47558 – net: stmmac: Disable Tx queues when reconfiguring the interface
https://notcve.org/view.php?id=CVE-2021-47558
In the Linux kernel, the following vulnerability has been resolved: net: stmmac: Disable Tx queues when reconfiguring the interface The Tx queues were not disabled in situations where the driver needed to stop the interface to apply a new configuration. This could result in a kernel panic when doing any of the 3 following actions: * reconfiguring the number of queues (ethtool -L) * reconfiguring the size of the ring buffers (ethtool -G) * installing/removing an XDP program (ip l set dev ethX xdp) Prevent the panic by making sure netif_tx_disable is called when stopping an interface. Without this patch, the following kernel panic can be observed when doing any of the actions above: Unable to handle kernel paging request at virtual address ffff80001238d040 [....] Call trace: dwmac4_set_addr+0x8/0x10 dev_hard_start_xmit+0xe4/0x1ac sch_direct_xmit+0xe8/0x39c __dev_queue_xmit+0x3ec/0xaf0 dev_queue_xmit+0x14/0x20 [...] [ end trace 0000000000000002 ]--- En el kernel de Linux, se resolvió la siguiente vulnerabilidad: net: stmmac: Deshabilitar las colas de Tx al reconfigurar la interfaz Las colas de Tx no se deshabilitaron en situaciones en las que el controlador necesitaba detener la interfaz para aplicar una nueva configuración. Esto podría provocar un pánico en el kernel al realizar cualquiera de las 3 acciones siguientes: * reconfigurar el número de colas (ethtool -L) * reconfigurar el tamaño de los búferes circulares (ethtool -G) * instalar/eliminar un programa XDP (ip l set dev ethX xdp) Evite el pánico asegurándose de que se llame a netif_tx_disable al detener una interfaz. Sin este parche, se puede observar el siguiente pánico del kernel al realizar cualquiera de las acciones anteriores: No se puede manejar la solicitud de paginación del kernel en la dirección virtual ffff80001238d040 [....] Seguimiento de llamadas: dwmac4_set_addr+0x8/0x10 dev_hard_start_xmit+0xe4/0x1ac sch_direct_xmit+ 0xe8/0x39c __dev_queue_xmit+0x3ec/0xaf0 dev_queue_xmit+0x14/0x20 [...] • https://git.kernel.org/stable/c/0366f7e06a6bee7eace3946a6b67fb88b828bc5c https://git.kernel.org/stable/c/a92f0eebb8dc008b9e8c51c6f7b8c93b27a29a43 https://git.kernel.org/stable/c/b270bfe697367776eca2e6759a71d700fb8d82a2 •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47557 – net/sched: sch_ets: don't peek at classes beyond 'nbands'
https://notcve.org/view.php?id=CVE-2021-47557
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_ets: don't peek at classes beyond 'nbands' when the number of DRR classes decreases, the round-robin active list can contain elements that have already been freed in ets_qdisc_change(). As a consequence, it's possible to see a NULL dereference crash, caused by the attempt to call cl->qdisc->ops->peek(cl->qdisc) when cl->qdisc is NULL: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 910 Comm: mausezahn Not tainted 5.16.0-rc1+ #475 Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014 RIP: 0010:ets_qdisc_dequeue+0x129/0x2c0 [sch_ets] Code: c5 01 41 39 ad e4 02 00 00 0f 87 18 ff ff ff 49 8b 85 c0 02 00 00 49 39 c4 0f 84 ba 00 00 00 49 8b ad c0 02 00 00 48 8b 7d 10 <48> 8b 47 18 48 8b 40 38 0f ae e8 ff d0 48 89 c3 48 85 c0 0f 84 9d RSP: 0000:ffffbb36c0b5fdd8 EFLAGS: 00010287 RAX: ffff956678efed30 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000002 RSI: ffffffff9b938dc9 RDI: 0000000000000000 RBP: ffff956678efed30 R08: e2f3207fe360129c R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffff956678efeac0 R13: ffff956678efe800 R14: ffff956611545000 R15: ffff95667ac8f100 FS: 00007f2aa9120740(0000) GS:ffff95667b800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 000000011070c000 CR4: 0000000000350ee0 Call Trace: <TASK> qdisc_peek_dequeued+0x29/0x70 [sch_ets] tbf_dequeue+0x22/0x260 [sch_tbf] __qdisc_run+0x7f/0x630 net_tx_action+0x290/0x4c0 __do_softirq+0xee/0x4f8 irq_exit_rcu+0xf4/0x130 sysvec_apic_timer_interrupt+0x52/0xc0 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0033:0x7f2aa7fc9ad4 Code: b9 ff ff 48 8b 54 24 18 48 83 c4 08 48 89 ee 48 89 df 5b 5d e9 ed fc ff ff 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa <53> 48 83 ec 10 48 8b 05 10 64 33 00 48 8b 00 48 85 c0 0f 85 84 00 RSP: 002b:00007ffe5d33fab8 EFLAGS: 00000202 RAX: 0000000000000002 RBX: 0000561f72c31460 RCX: 0000561f72c31720 RDX: 0000000000000002 RSI: 0000561f72c31722 RDI: 0000561f72c31720 RBP: 000000000000002a R08: 00007ffe5d33fa40 R09: 0000000000000014 R10: 0000000000000000 R11: 0000000000000246 R12: 0000561f7187e380 R13: 0000000000000000 R14: 0000000000000000 R15: 0000561f72c31460 </TASK> Modules linked in: sch_ets sch_tbf dummy rfkill iTCO_wdt intel_rapl_msr iTCO_vendor_support intel_rapl_common joydev virtio_balloon lpc_ich i2c_i801 i2c_smbus pcspkr ip_tables xfs libcrc32c crct10dif_pclmul crc32_pclmul crc32c_intel ahci libahci ghash_clmulni_intel serio_raw libata virtio_blk virtio_console virtio_net net_failover failover sunrpc dm_mirror dm_region_hash dm_log dm_mod CR2: 0000000000000018 Ensuring that 'alist' was never zeroed [1] was not sufficient, we need to remove from the active list those elements that are no more SP nor DRR. [1] https://lore.kernel.org/netdev/60d274838bf09777f0371253416e8af71360bc08.1633609148.git.dcaratti@redhat.com/ v3: fix race between ets_qdisc_change() and ets_qdisc_dequeue() delisting DRR classes beyond 'nbands' in ets_qdisc_change() with the qdisc lock acquired, thanks to Cong Wang. v2: when a NULL qdisc is found in the DRR active list, try to dequeue skb from the next list item. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net/sched: sch_ets: no mire las clases más allá de 'nbands' cuando el número de clases DRR disminuye, la lista activa por turnos puede contener elementos que ya han sido liberados en ets_qdisc_change(). Como consecuencia, es posible ver un bloqueo de desreferencia NULL, causado por el intento de llamar a cl->qdisc->ops->peek(cl->qdisc) cuando cl->qdisc es NULL: ERROR: desreferencia del puntero NULL del kernel, dirección: 0000000000000018 #PF: acceso de lectura del supervisor en modo kernel #PF: error_code(0x0000) - página no presente PGD 0 P4D 0 Ups: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 910 Comm: mausezahn Not tainted 5.16 .0-rc1+ #475 Nombre de hardware: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 01/04/2014 RIP: 0010:ets_qdisc_dequeue+0x129/0x2c0 [sch_ets] Código: c5 01 41 39 ad e4 02 00 00 0f 87 18 ff ff ff 49 8b 85 c0 02 00 00 49 39 c4 0f 84 ba 00 00 00 49 8b ad c0 02 00 00 48 8b 7d 10 <48> 8b 47 48 8b 40 38 0f ae e8 ff d0 48 89 c3 48 85 c0 0f 84 9d RSP: 0000:ffffbb36c0b5fdd8 EFLAGS: 00010287 RAX: ffff956678efed30 RBX: 0000000000000000 RCX: 00000000000 00000 RDX: 0000000000000002 RSI: ffffffff9b938dc9 RDI: 0000000000000000 RBP: ffff956678efed30 R08: e2f3207fe360129c R09: 000000000000000000000 R10 : 0000000000000001 R11: 0000000000000001 R12: ffff956678efeac0 R13: ffff956678efe800 R14: ffff956611545000 R15: ffff95667ac8f100 FS: a9120740(0000) GS:ffff95667b800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 0000011070c000 CR4: 0000000000350ee0 Seguimiento de llamadas: qdisc_peek_dequeued+0x29/0x70 [sch_ets] tbf_dequeue+0x22/0x260 [sch_tbf] __qdisc_run+0x7f/0x630 net_tx_action+0x290/0x4c0 ee/0x4f8 irq_exit_rcu+0xf4/0x130 sysvec_apic_timer_interrupt+0x52/0xc0 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0033:0x7f2aa7fc9ad4 Código: b9 ff ff 48 8b 54 24 18 48 83 c4 08 48 89 ee 48 89 df 5b 5d e9 ed fc ff ff 0f 1f 0 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa <53> 48 83 ec 10 48 8b 05 10 64 33 00 48 8b 00 48 85 c0 0f 85 84 00 RSP: 002b:00007ffe5d33fab8 EFLAGS: 00000202 RAX: 0000002 RBX: 0000561f72c31460 RCX: 0000561f72c31720 RDX: 0000000000000002 RSI: 0000561f72c31722 RDI: 0000561f72c31720 RBP: 000000000000002a R08: 00007ffe5d33fa40 R09: 00000000000000014 R10: 0000000000000000 R11: 000000000000246 R12: 0000561f7187e380 R13: 0000000000000000 R14: 0000000000000000 R15: 0000561f72c31460 Módulos vinculados en: sch_ets sch_tbf dummy matar iTCO_wdt intel_rapl_msr iTCO_vendor_support intel_rapl_common joydev virtio_balloon lpc_ich i2c_i801 i2c_smbus pcspkr ip_tables xfs libcrc32c crct10dif_pclmul crc32_pclmul crc32c_intel ahci libahci ghash_clmulni_intel serio_raw libata virtio_blk virtio_console virtio_net net_failover failover sunrpc dm_mirror dm_region_hash dm _log dm_mod CR2: 0000000000000018 Asegurarse de que 'alist' nunca se pusiera a cero [1] no fue suficiente, debemos eliminarlo de la lista activa aquellos elementos que ya no son PS ni RRD. [1] https://lore.kernel.org/netdev/60d274838bf09777f0371253416e8af71360bc08.1633609148.git.dcaratti@redhat.com/ v3: corrige la ejecución entre ets_qdisc_change() y ets_qdisc_dequeue() eliminando las clases de DRR más allá de 'nbands' en c_cambio() con el bloqueo qdisc adquirido, gracias a Cong Wang. v2: cuando se encuentra una qdisc NULL en la lista activa de DRR, intente sacar de la cola a skb del siguiente elemento de la lista. • https://git.kernel.org/stable/c/dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 https://git.kernel.org/stable/c/ae2659d2c670252759ee9c823c4e039c0e05a6f2 https://git.kernel.org/stable/c/e25bdbc7e951ae5728fee1f4c09485df113d013c https://git.kernel.org/stable/c/de6d25924c2a8c2988c6a385990cafbe742061bf •
CVSS: 5.5EPSS: 0%CPEs: 2EXPL: 0CVE-2021-47556 – ethtool: ioctl: fix potential NULL deref in ethtool_set_coalesce()
https://notcve.org/view.php?id=CVE-2021-47556
In the Linux kernel, the following vulnerability has been resolved: ethtool: ioctl: fix potential NULL deref in ethtool_set_coalesce() ethtool_set_coalesce() now uses both the .get_coalesce() and .set_coalesce() callbacks. But the check for their availability is buggy, so changing the coalesce settings on a device where the driver provides only _one_ of the callbacks results in a NULL pointer dereference instead of an -EOPNOTSUPP. Fix the condition so that the availability of both callbacks is ensured. This also matches the netlink code. Note that reproducing this requires some effort - it only affects the legacy ioctl path, and needs a specific combination of driver options: - have .get_coalesce() and .coalesce_supported but no .set_coalesce(), or - have .set_coalesce() but no .get_coalesce(). Here eg. ethtool doesn't cause the crash as it first attempts to call ethtool_get_coalesce() and bails out on error. En el kernel de Linux, se resolvió la siguiente vulnerabilidad: ethtool: ioctl: corrige un posible deref NULL en ethtool_set_coalesce() ethtool_set_coalesce() ahora usa las devoluciones de llamada .get_coalesce() y .set_coalesce(). • https://git.kernel.org/stable/c/f3ccfda1931977b80267ba54070a1aeafa18f6ca https://git.kernel.org/stable/c/abfdd9e2f0f9699015d72317f74154d3e53664e6 https://git.kernel.org/stable/c/0276af2176c78771da7f311621a25d7608045827 https://access.redhat.com/security/cve/CVE-2021-47556 https://bugzilla.redhat.com/show_bug.cgi?id=2283393 • CWE-476: NULL Pointer Dereference •
CVSS: 4.4EPSS: 0%CPEs: 4EXPL: 0CVE-2021-47555 – net: vlan: fix underflow for the real_dev refcnt
https://notcve.org/view.php?id=CVE-2021-47555
In the Linux kernel, the following vulnerability has been resolved: net: vlan: fix underflow for the real_dev refcnt Inject error before dev_hold(real_dev) in register_vlan_dev(), and execute the following testcase: ip link add dev dummy1 type dummy ip link add name dummy1.100 link dummy1 type vlan id 100 ip link del dev dummy1 When the dummy netdevice is removed, we will get a WARNING as following: ======================================================================= refcount_t: decrement hit 0; leaking memory. WARNING: CPU: 2 PID: 0 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0 and an endless loop of: ======================================================================= unregister_netdevice: waiting for dummy1 to become free. Usage count = -1073741824 That is because dev_put(real_dev) in vlan_dev_free() be called without dev_hold(real_dev) in register_vlan_dev(). It makes the refcnt of real_dev underflow. Move the dev_hold(real_dev) to vlan_dev_init() which is the call-back of ndo_init(). That makes dev_hold() and dev_put() for vlan's real_dev symmetrical. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net: vlan: corrige el desbordamiento insuficiente para real_dev refcnt Inyecte el error antes de dev_hold(real_dev) en Register_vlan_dev() y ejecute el siguiente caso de prueba: ip link add dev dummy1 tipo dummy ip link add nombre dummy1.100 link dummy1 tipo vlan id 100 ip link del dev dummy1 Cuando se elimina el dispositivo de red ficticio, recibiremos una ADVERTENCIA como la siguiente: ===================== ==================================================== = refcount_t: decremento hit 0; pérdida de memoria. • https://git.kernel.org/stable/c/700602b662d7eaa816b1a3cb0abe7a85de358fd4 https://git.kernel.org/stable/c/e04a7a84bb77f9cdf4475340fe931389bc72331c https://git.kernel.org/stable/c/21032425c36ff85f16e72ca92193a8c401e4acd5 https://git.kernel.org/stable/c/fca96b3f852a1b369b7b2844ce357cd689879934 https://git.kernel.org/stable/c/5e44178864b38dd70b877985abd7d86fdb95f27d https://git.kernel.org/stable/c/6e800ee43218a56acc93676bbb3d93b74779e555 https://git.kernel.org/stable/c/f7fc72a508cf115c273a7a29350069def1041890 https://git.kernel.org/stable/c/01d9cc2dea3fde3bad6d27f464eff4634 •