Withdrawn by the publisher.

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

io_uring: preserve task restrictions across exec

Per-task restrictions apply to all rings created by a task. Once installed, they should not be dropped across exec.

For a task that has used io_uring, the exec cancellation path calls __io_uring_free(). This frees both the task context and the per-task restriction, so a ring created after exec is unrestricted.

Split task context cleanup into io_uring_free_tctx(), and use it from the exec cancellation path. Keep __io_uring_free() for final task cleanup, where both the context and restriction are released.

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

io_uring: preserve task restrictions across exec

Per-task restrictions apply to all rings created by a task. Once installed, they should not be dropped across exec.

For a task that has used io_uring, the exec cancellation path calls __io_uring_free(). This frees both the task context and the per-task restriction, so a ring created after exec is unrestricted.

Split task context cleanup into io_uring_free_tctx(), and use it from the exec cancellation path. Keep __io_uring_free() for final task cleanup, where both the context and restriction are released.

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:18.04:LTS: linux-azure, Ubuntu:18.04:LTS: linux-azure-5.3, Ubuntu:18.04:LTS: linux-azure-edge, Ubuntu:18.04:LTS: linux-gcp, Ubuntu:18.04:LTS: linux-gcp-5.3, Ubuntu:18.04:LTS: linux-gke-4.15, Ubuntu:18.04:LTS: linux-gke-5.4 and 117 more

In the Linux kernel, the following vulnerability has been resolved: io_uring: preserve task restrictions across exec Per-task restrictions apply to all rings created by a task. Once installed, they should not be dropped across exec. For a task that has used io_uring, the exec cancellation path calls __io_uring_free(). This frees both the task context and the per-task restriction, so a ring created after exec is unrestricted. Split task context cleanup into io_uring_free_tctx(), and use it from the exec cancellation path. Keep __io_uring_free() for final task cleanup, where both the context and restriction are released.

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen, darunter möglicherweise Speicherbeschädigungen, die Offenlegung oder Manipulation von Daten sowie Denial-of-Service-Zustände.