diff options
| author |   Theodore Ts'o <tytso@mit.edu> | 2013-11-03 06:54:51 -0500 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2013-11-03 18:18:48 -0500 |
| commit | 301f0595c0e788edacc3521c4caa90b4e56ffee1 (patch) | |
| tree | df43a0a76d8cfa5783154154a60653a7d51c2d8e /drivers/char | |
| parent | random: make add_timer_randomness() fill the nonblocking pool first (diff) | |
| download | linux-dev-301f0595c0e788edacc3521c4caa90b4e56ffee1.tar.xz linux-dev-301f0595c0e788edacc3521c4caa90b4e56ffee1.zip | |
random: printk notifications for urandom pool initialization
Print a notification to the console when the nonblocking pool is
initialized. Also printk a warning when a process tries reading from
/dev/urandom before it is fully initialized.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/random.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 62923138e77a..a19a7a63ec35 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -655,6 +655,9 @@ retry: r->entropy_total += nbits; if (!r->initialized && nbits > 0) { if (r->entropy_total > 128) { + if (r == &nonblocking_pool) + pr_notice("random: %s pool is initialized\n", + r->name); r->initialized = 1; r->entropy_total = 0; } @@ -1327,7 +1330,14 @@ 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) { - int ret = extract_entropy_user(&nonblocking_pool, buf, nbytes); + 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); + + ret = extract_entropy_user(&nonblocking_pool, buf, nbytes); trace_urandom_read(8 * nbytes, ENTROPY_BITS(&nonblocking_pool), ENTROPY_BITS(&input_pool)); |