CVSS: -EPSS: 0%CPEs: 7EXPL: 0CVE-2021-47603 – audit: improve robustness of the audit queue handling
https://notcve.org/view.php?id=CVE-2021-47603
In the Linux kernel, the following vulnerability has been resolved: audit: improve robustness of the audit queue handling If the audit daemon were ever to get stuck in a stopped state the kernel's kauditd_thread() could get blocked attempting to send audit records to the userspace audit daemon. With the kernel thread blocked it is possible that the audit queue could grow unbounded as certain audit record generating events must be exempt from the queue limits else the system enter a deadlock state. This patch resolves this problem by lowering the kernel thread's socket sending timeout from MAX_SCHEDULE_TIMEOUT to HZ/10 and tweaks the kauditd_send_queue() function to better manage the various audit queues when connection problems occur between the kernel and the audit daemon. With this patch, the backlog may temporarily grow beyond the defined limits when the audit daemon is stopped and the system is under heavy audit pressure, but kauditd_thread() will continue to make progress and drain the queues as it would for other connection problems. For example, with the audit daemon put into a stopped state and the system configured to audit every syscall it was still possible to shutdown the system without a kernel panic, deadlock, etc.; granted, the system was slow to shutdown but that is to be expected given the extreme pressure of recording every syscall. The timeout value of HZ/10 was chosen primarily through experimentation and this developer's "gut feeling". There is likely no one perfect value, but as this scenario is limited in scope (root privileges would be needed to send SIGSTOP to the audit daemon), it is likely not worth exposing this as a tunable at present. • https://git.kernel.org/stable/c/5b52330bbfe63b3305765354d6046c9f7f89c011 https://git.kernel.org/stable/c/a0c48115cd2343231585f2f5e609b2ac9aa4e0af https://git.kernel.org/stable/c/75fdb751f84727d614deea0571a1490c3225d83a https://git.kernel.org/stable/c/8389f50ceb854cb437fefb9330d5024ed3c7c1f5 https://git.kernel.org/stable/c/0d3277eabd542fb662be23696e5ec9f390d688e1 https://git.kernel.org/stable/c/4cc6badff97f74d0fce65f9784b5df3b64e4250b https://git.kernel.org/stable/c/a5f4d17daf2e6cd7c1d9676b476147f6b4ac53f2 https://git.kernel.org/stable/c/f4b3ee3c85551d2d343a3ba1593040665 •
CVSS: -EPSS: 0%CPEs: 5EXPL: 0CVE-2021-47602 – mac80211: track only QoS data frames for admission control
https://notcve.org/view.php?id=CVE-2021-47602
In the Linux kernel, the following vulnerability has been resolved: mac80211: track only QoS data frames for admission control For admission control, obviously all of that only works for QoS data frames, otherwise we cannot even access the QoS field in the header. Syzbot reported (see below) an uninitialized value here due to a status of a non-QoS nullfunc packet, which isn't even long enough to contain the QoS header. Fix this to only do anything for QoS data packets. En el kernel de Linux, se resolvió la siguiente vulnerabilidad: mac80211: rastrea solo frameworks de datos QoS para control de admisión. Para el control de admisión, obviamente todo eso solo funciona para frameworks de datos QoS; de lo contrario, ni siquiera podemos acceder al campo QoS en el encabezado. Syzbot informó (ver más abajo) un valor no inicializado aquí debido al estado de un paquete nullfunc sin QoS, que ni siquiera es lo suficientemente largo para contener el encabezado de QoS. Solucione este problema para hacer algo únicamente con los paquetes de datos QoS. • https://git.kernel.org/stable/c/02219b3abca59fca81711bfe7ee78df7abad97ce https://git.kernel.org/stable/c/69f054d6642c8f6173724ce17e7ee3ff66b8f682 https://git.kernel.org/stable/c/46b9e29db2012a4d2a40a26101862e002ccf387b https://git.kernel.org/stable/c/eed897a22230e3231a740eddd7d6d95ba476625f https://git.kernel.org/stable/c/42d08e97b196479f593499e887a9ab81446a34b9 https://git.kernel.org/stable/c/d5e568c3a4ec2ddd23e7dc5ad5b0c64e4f22981a •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2021-47601 – tee: amdtee: fix an IS_ERR() vs NULL bug
https://notcve.org/view.php?id=CVE-2021-47601
In the Linux kernel, the following vulnerability has been resolved: tee: amdtee: fix an IS_ERR() vs NULL bug The __get_free_pages() function does not return error pointers it returns NULL so fix this condition to avoid a NULL dereference. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: tee: amdtee: corrige un error IS_ERR() vs NULL La función __get_free_pages() no devuelve punteros de error, devuelve NULL, así que corrija esta condición para evitar una desreferencia a NULL. • https://git.kernel.org/stable/c/757cc3e9ff1d72d014096399d6e2bf03974d9da1 https://git.kernel.org/stable/c/640e28d618e82be78fb43b4bf5113bc90d6aa442 https://git.kernel.org/stable/c/832f3655c6138c23576ed268e31cc76e0f05f2b1 https://git.kernel.org/stable/c/9d7482771fac8d8e38e763263f2ca0ca12dd22c6 •
CVSS: -EPSS: 0%CPEs: 8EXPL: 0CVE-2021-47600 – dm btree remove: fix use after free in rebalance_children()
https://notcve.org/view.php?id=CVE-2021-47600
In the Linux kernel, the following vulnerability has been resolved: dm btree remove: fix use after free in rebalance_children() Move dm_tm_unlock() after dm_tm_dec(). En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: dm btree remove: corrige el use after free en rebalance_children() Mueve dm_tm_unlock() después de dm_tm_dec(). • https://git.kernel.org/stable/c/a48f6a2bf33734ec5669ee03067dfb6c5b4818d6 https://git.kernel.org/stable/c/66ea642af6fd4eacb5d0271a922130fcf8700424 https://git.kernel.org/stable/c/b03abd0aa09c05099f537cb05b8460c4298f0861 https://git.kernel.org/stable/c/293f957be5e39720778fb1851ced7f5fba6d51c3 https://git.kernel.org/stable/c/501ecd90efdc9b2edc6c28852ecd098a4adf8f00 https://git.kernel.org/stable/c/0e21e6cd5eebfc929ac5fa3b97ca2d4ace3cb6a3 https://git.kernel.org/stable/c/607beb420b3fe23b948a9bf447d993521a02fbbb https://git.kernel.org/stable/c/1b8d2789dad0005fd5e7d35dab26a8e12 •
CVSS: -EPSS: 0%CPEs: 2EXPL: 0CVE-2021-47599 – btrfs: use latest_dev in btrfs_show_devname
https://notcve.org/view.php?id=CVE-2021-47599
In the Linux kernel, the following vulnerability has been resolved: btrfs: use latest_dev in btrfs_show_devname The test case btrfs/238 reports the warning below: WARNING: CPU: 3 PID: 481 at fs/btrfs/super.c:2509 btrfs_show_devname+0x104/0x1e8 [btrfs] CPU: 2 PID: 1 Comm: systemd Tainted: G W O 5.14.0-rc1-custom #72 Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 Call trace: btrfs_show_devname+0x108/0x1b4 [btrfs] show_mountinfo+0x234/0x2c4 m_show+0x28/0x34 seq_read_iter+0x12c/0x3c4 vfs_read+0x29c/0x2c8 ksys_read+0x80/0xec __arm64_sys_read+0x28/0x34 invoke_syscall+0x50/0xf8 do_el0_svc+0x88/0x138 el0_svc+0x2c/0x8c el0t_64_sync_handler+0x84/0xe4 el0t_64_sync+0x198/0x19c Reason: While btrfs_prepare_sprout() moves the fs_devices::devices into fs_devices::seed_list, the btrfs_show_devname() searches for the devices and found none, leading to the warning as in above. Fix: latest_dev is updated according to the changes to the device list. That means we could use the latest_dev->name to show the device name in /proc/self/mounts, the pointer will be always valid as it's assigned before the device is deleted from the list in remove or replace. The RCU protection is sufficient as the device structure is freed after synchronization. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: btrfs: utilice Latest_dev en btrfs_show_devname El caso de prueba btrfs/238 informa la siguiente advertencia: ADVERTENCIA: CPU: 3 PID: 481 en fs/btrfs/super.c:2509 btrfs_show_devname+0x104 /0x1e8 [btrfs] CPU: 2 PID: 1 Comunicación: systemd Contaminado: GWO 5.14.0-rc1-custom #72 Nombre de hardware: QEMU Máquina virtual QEMU, BIOS 0.0.0 06/02/2015 Rastreo de llamadas: btrfs_show_devname+0x108/ 0x1b4 [btrfs] show_mountinfo+0x234/0x2c4 m_show+0x28/0x34 seq_read_iter+0x12c/0x3c4 vfs_read+0x29c/0x2c8 ksys_read+0x80/0xec __arm64_sys_read+0x28/0x34 x50/0xf8 do_el0_svc+0x88/0x138 el0_svc+0x2c/0x8c el0t_64_sync_handler +0x84/0xe4 el0t_64_sync+0x198/0x19c Motivo: mientras btrfs_prepare_sprout() mueve fs_devices::devices a fs_devices::seed_list, btrfs_show_devname() busca los dispositivos y no encuentra ninguno, lo que genera la advertencia como se muestra arriba. Solución: last_dev se actualiza según los cambios en la lista de dispositivos. Eso significa que podríamos usar el último_dev->name para mostrar el nombre del dispositivo en /proc/self/mounts, el puntero siempre será válido tal como está asignado antes de que el dispositivo se elimine de la lista en eliminar o reemplazar. La protección de la RCU es suficiente, ya que la estructura del dispositivo se libera después de la sincronización. • https://git.kernel.org/stable/c/e342c2558016ead462f376b6c6c2ac5efc17f3b1 https://git.kernel.org/stable/c/6605fd2f394bba0a0059df2b6cfc87b0b6d393a2 •