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

KEYS: Fix key_reject_and_link() race with keyring restriction

The restrict_link check in key_reject_and_link() is done before taking the keyring semaphore, racing with a concurrent keyring_restrict() that installs the restriction while holding the semaphore in write mode.

Move the check to after __key_link_lock(), so it is done under the semaphore, matching the pattern used in __key_create_or_update().

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

KEYS: Fix key_reject_and_link() race with keyring restriction

The restrict_link check in key_reject_and_link() is done before taking the keyring semaphore, racing with a concurrent keyring_restrict() that installs the restriction while holding the semaphore in write mode.

Move the check to after __key_link_lock(), so it is done under the semaphore, matching the pattern used in __key_create_or_update().

Affected: Ubuntu:Pro:14.04:LTS: linux-azure, Ubuntu:Pro:16.04:LTS: linux-aws-hwe, Ubuntu:Pro:16.04:LTS: linux-azure, Ubuntu:Pro:16.04:LTS: linux-gcp, Ubuntu:Pro:16.04:LTS: linux-hwe, Ubuntu:16.04:LTS: linux-hwe-edge, Ubuntu:Pro:16.04:LTS: linux-oracle, Ubuntu:Pro:18.04:LTS: linux, Ubuntu:Pro:18.04:LTS: linux-aws, Ubuntu:18.04:LTS: linux-aws-5.0 and 249 more

In the Linux kernel, the following vulnerability has been resolved: KEYS: Fix key_reject_and_link() race with keyring restriction The restrict_link check in key_reject_and_link() is done before taking the keyring semaphore, racing with a concurrent keyring_restrict() that installs the restriction while holding the semaphore in write mode. Move the check to after __key_link_lock(), so it is done under the semaphore, matching the pattern used in __key_create_or_update().