From: Theodore Ts'o Date: Mon, 13 Jun 2016 14:10:51 +0000 (-0400) Subject: random: print a warning for the first ten uninitialized random users X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=9b4d008787f864f17d008c9c15bbe8a0f7e2fc24;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git random: print a warning for the first ten uninitialized random users Since systemd is consistently using /dev/urandom before it is initialized, we can't see the other potentially dangerous users of /dev/urandom immediately after boot. So print the first ten such complaints instead. Cc: stable@kernel.org Signed-off-by: Theodore Ts'o --- diff --git a/drivers/char/random.c b/drivers/char/random.c index 4e2627a8d226..d057438266bb 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -1458,12 +1458,16 @@ random_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) static ssize_t urandom_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) { + static int maxwarn = 10; int ret; - if (unlikely(nonblocking_pool.initialized == 0)) - printk_once(KERN_NOTICE "random: %s urandom read " - "with %d bits of entropy available\n", - current->comm, nonblocking_pool.entropy_total); + if (unlikely(nonblocking_pool.initialized == 0) && + maxwarn > 0) { + maxwarn--; + printk(KERN_NOTICE "random: %s: uninitialized urandom read " + "(%zd bytes read, %d bits of entropy available)\n", + current->comm, nbytes, nonblocking_pool.entropy_total); + } nbytes = min_t(size_t, nbytes, INT_MAX >> (ENTROPY_SHIFT + 3)); ret = extract_entropy_user(&nonblocking_pool, buf, nbytes);