On Mon, 18 Oct 2021 10:42:25 +0800, Zheng Liang wrote:

In bfq_pd_alloc(), the function bfqg_stats_init() init bfqg. If
blkg_rwstat_init() init bfqg_stats->bytes successful and init
bfqg_stats->ios failed, bfqg_stats_init() return failed, bfqg will
be freed. But blkg_rwstat->cpu_cnt is not deleted from the list of
percpu_counters. If we traverse the list of percpu_counters, It will
have UAF problem.

[...]

Applied, thanks!

[1/1] block, bfq: fix UAF problem in bfqg_stats_init()
      commit: 2fc428f6b7ca80794cb9928c90d4de524366659f

Best regards,
-- 
Jens Axboe