random: fix possible sleeping allocation from irq context

We can do a sleeping allocation from an irq context when CONFIG_NUMA
is enabled.  Fix this by initializing the NUMA crng instances in a
workqueue.

Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot+9de458f6a5e713ee8c1a@syzkaller.appspotmail.com
Fixes: 8ef35c866f ("random: set up the NUMA crng instances...")
Cc: stable@vger.kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Theodore Ts'o 2018-04-23 18:51:28 -04:00
parent d848e5f8e1
commit 6c1e851c4e

View File

@ -789,7 +789,7 @@ static void crng_initialize(struct crng_state *crng)
}
#ifdef CONFIG_NUMA
static void numa_crng_init(void)
static void do_numa_crng_init(struct work_struct *work)
{
int i;
struct crng_state *crng;
@ -810,6 +810,13 @@ static void numa_crng_init(void)
kfree(pool);
}
}
static DECLARE_WORK(numa_crng_init_work, do_numa_crng_init);
static void numa_crng_init(void)
{
schedule_work(&numa_crng_init_work);
}
#else
static void numa_crng_init(void) {}
#endif