crypto: cryptd - Protect per-CPU resource by disabling BH.
The access to cryptd_queue::cpu_queue is synchronized by disabling preemption in cryptd_enqueue_request() and disabling BH in cryptd_queue_worker(). This implies that access is allowed from BH. If cryptd_enqueue_request() is invoked from preemptible context _and_ soft interrupt then this can lead to list corruption since cryptd_enqueue_request() is not protected against access from soft interrupt. Replace get_cpu() in cryptd_enqueue_request() with local_bh_disable() to ensure BH is always disabled. Remove preempt_disable() from cryptd_queue_worker() since it is not needed because local_bh_disable() ensures synchronisation. Fixes: 254eff77 ("crypto: cryptd - Per-CPU thread implementation...") Signed-off-by:Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by:
Herbert Xu <herbert@gondor.apana.org.au>
parent
42a01af3
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