random: initialize the last_time field in struct timer_rand_state
authorTheodore Ts'o <tytso@mit.edu>
Sun, 3 Nov 2013 21:40:53 +0000 (16:40 -0500)
committerTheodore Ts'o <tytso@mit.edu>
Sun, 3 Nov 2013 23:20:05 +0000 (18:20 -0500)
commit644008df899ec252e78db28c1b6d6b86779aada8
tree4d33e8e3bb0d9c487bc337e2b9c44387bc847a71
parentae9ecd92ddabc250817baa7eb401df3cfbd4c2da
random: initialize the last_time field in struct timer_rand_state

Since we initialize jiffies to wrap five minutes before boot (see
INITIAL_JIFFIES defined in include/linux/jiffies.h) it's important to
make sure the last_time field is initialized to INITIAL_JIFFIES.
Otherwise, the entropy estimator will overestimate the amount of
entropy resulting from the first call to add_timer_randomness(),
generally by about 8 bits.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
drivers/char/random.c