In the Linux kernel, the following vulnerability has been resolved: gfs2: fix quota init duplicate scan gfs2_quota_init() checks for duplicate quota_change IDs while holding qd_lock and the quota hash bucket bitlock. That path used gfs2_qd_search_bucket(), which takes a lockref reference via lockref_get_not_dead(). On PREEMPT_RT this may sleep, which is not allowed under the bucket bitlock, triggering "sleeping function called from invalid context". Use a no-ref bucket lookup in this path, then continue duplicate handling without taking a lockref there. Refactor gfs2_qd_search_bucket() to build on top of the no-ref helper so lookup traversal stays in one place. This patch fixes a bug reported by syzbot.
https://git.kernel.org/stable/c/b99a1f0f18ee50445907f55069e88bcfd8947383
https://git.kernel.org/stable/c/812a766e2b0a8f4d094393fad13475c57f5f86db
https://git.kernel.org/stable/c/7fdcf16e5e14e11028f5bcaa6d25075eb5e876a0