In the Linux kernel, the following vulnerability has been resolved:

blk-iolatency: Fix memory leak on add_disk() failures

When a gendisk is successfully initialized but add_disk() fails such as when a loop device has invalid number of minor device numbers specified, blkcg_init_disk() is called during init and then blkcg_exit_disk() during error handling. Unfortunately, iolatency gets initialized in the former but doesn't get cleaned up in the latter.

This is because, in non-error cases, the cleanup is performed by del_gendisk() calling rq_qos_exit(), the assumption being that rq_qos policies, iolatency being one of them, can only be activated once the disk is fully registered and visible. That assumption is true for wbt and iocost, but not so for iolatency as it gets initialized before add_disk() is called.

It is desirable to lazy-init rq_qos policies because they are optional features and add to hot path overhead once initialized - each IO has to walk all the registered rq_qos policies. So, we want to switch iolatency to lazy init too. However, that's a bigger change. As a fix for the immediate problem, let's just add an extra call to rq_qos_exit() in blkcg_exit_disk(). This is safe because duplicate calls to rq_qos_exit() become noop's.

In the Linux kernel, the following vulnerability has been resolved:

blk-iolatency: Fix memory leak on add_disk() failures

When a gendisk is successfully initialized but add_disk() fails such as when a loop device has invalid number of minor device numbers specified, blkcg_init_disk() is called during init and then blkcg_exit_disk() during error handling. Unfortunately, iolatency gets initialized in the former but doesn't get cleaned up in the latter.

This is because, in non-error cases, the cleanup is performed by del_gendisk() calling rq_qos_exit(), the assumption being that rq_qos policies, iolatency being one of them, can only be activated once the disk is fully registered and visible. That assumption is true for wbt and iocost, but not so for iolatency as it gets initialized before add_disk() is called.

It is desirable to lazy-init rq_qos policies because they are optional features and add to hot path overhead once initialized - each IO has to walk all the registered rq_qos policies. So, we want to switch iolatency to lazy init too. However, that's a bigger change. As a fix for the immediate problem, let's just add an extra call to rq_qos_exit() in blkcg_exit_disk(). This is safe because duplicate calls to rq_qos_exit() become noop's.

kernel: seg6: fix the iif in the IPv6 socket control block Kernel: race when faulting a device private page in memory manager kernel: use-after-free in l1oip timer handlers kernel: Rate limit overflow messages in r8152 in intr_callback kernel: vmwgfx: use-after-free in vmw_cmd_res_check kernel: vmwgfx: use-after-free in vmw_execbuf_tie_context hw: Intel: Gather Data Sampling (GDS) side channel vulnerability kernel: Information leak in l2cap_parse_conf_req in net/bluetooth/l2cap_core.c kernel: perf: Fix perf_pending_task() UaF kernel: gpiolib: fix memory leak in gpiochip_setup_dev() kernel: memcg: fix possible use-after-free in memcg_write_event_control() kernel: mm/khugepaged: invoke MMU notifiers in shmem/file collapse paths kernel: char: tpm: Protect tpm_pm_suspend with locks kernel: ixgbevf: Fix resource leak in ixgbevf_init_module() kernel: dax: make sure inodes are flushed before destroy cache kernel: watch_queue: Actually free the watch kernel: watch_queue: Fix NULL dereference in error cleanup kernel: rtc: pl031: fix rtc features null pointer dereference kernel: tpm: fix reference counting for struct tpm_chip kernel: NFSv4: Don't hold the layoutget locks across multiple RPC calls kernel: xprtrdma: treat all calls not a bcall when bc_serv is NULL kernel: net: ipv6: unexport __init-annotated seg6_hmac_init() kernel: af_unix: Fix a data-race in unix_dgram_peer_wake_me(). kernel: regulator: scmi: Fix refcount leak in scmi_regulator_probe kernel: mm/mempolicy: fix uninit-v…

Affected: Ubuntu:16.04:LTS: linux-hwe-edge, Ubuntu:18.04:LTS: linux-aws-5.0, Ubuntu:18.04:LTS: linux-aws-5.3, Ubuntu:Pro:18.04:LTS: linux-aws-5.4, Ubuntu:18.04:LTS: linux-azure, Ubuntu:18.04:LTS: linux-azure-5.3, Ubuntu:Pro:18.04:LTS: linux-azure-5.4, Ubuntu:18.04:LTS: linux-azure-edge, Ubuntu:18.04:LTS: linux-gcp, Ubuntu:18.04:LTS: linux-gcp-5.3 and 142 more

In the Linux kernel, the following vulnerability has been resolved: blk-iolatency: Fix memory leak on add_disk() failures When a gendisk is successfully initialized but add_disk() fails such as when a loop device has invalid number of minor device numbers specified, blkcg_init_disk() is called during init and then blkcg_exit_disk() during error handling. Unfortunately, iolatency gets initialized in the former but doesn't get cleaned up in the latter. This is because, in non-error cases, the cleanup is performed by del_gendisk() calling rq_qos_exit(), the assumption being that rq_qos policies, iolatency being one of them, can only be activated once the disk is fully registered and visible. That assumption is true for wbt and iocost, but not so for iolatency as it gets initialized before add_disk() is called. It is desirable to lazy-init rq_qos policies because they are optional features and add to hot path overhead once initialized - each IO has to walk all the registered rq_qos policies. So, we want to switch iolatency to lazy init too. However, that's a bigger change. As a fix for the immediate problem, let's just add an extra call to rq_qos_exit() in blkcg_exit_disk(). This is safe because duplicate calls to rq_qos_exit() become noop's.

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen Denial of Service Angriff durchzuführen und andere nicht näher spezifizierte Angriffe durchzuführen.