diff options
author | Ingo Molnar <mingo@kernel.org> | 2014-07-28 10:03:00 +0200 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2014-07-28 10:03:00 +0200 |
commit | ca5bc6cd5de5b53eb8fd6fea39aa3fe2a1e8c3d9 (patch) | |
tree | 75beaae2d4b6bc654eb28994dd5906d8dcf5ef46 /drivers/char/random.c | |
parent | c1221321b7c25b53204447cff9949a6d5a7ddddc (diff) | |
parent | d8d28c8f00e84a72e8bee39a85835635417bee49 (diff) | |
download | linux-next-ca5bc6cd5de5b53eb8fd6fea39aa3fe2a1e8c3d9.tar.gz |
Merge branch 'sched/urgent' into sched/core, to merge fixes before applying new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/char/random.c')
-rw-r--r-- | drivers/char/random.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 0a7ac0a7b252..71529e196b84 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -641,7 +641,7 @@ retry: } while (unlikely(entropy_count < pool_size-2 && pnfrac)); } - if (entropy_count < 0) { + if (unlikely(entropy_count < 0)) { pr_warn("random: negative entropy/overflow: pool %s count %d\n", r->name, entropy_count); WARN_ON(1); @@ -981,7 +981,7 @@ static size_t account(struct entropy_store *r, size_t nbytes, int min, int reserved) { int entropy_count, orig; - size_t ibytes; + size_t ibytes, nfrac; BUG_ON(r->entropy_count > r->poolinfo->poolfracbits); @@ -999,7 +999,17 @@ retry: } if (ibytes < min) ibytes = 0; - if ((entropy_count -= ibytes << (ENTROPY_SHIFT + 3)) < 0) + + if (unlikely(entropy_count < 0)) { + pr_warn("random: negative entropy count: pool %s count %d\n", + r->name, entropy_count); + WARN_ON(1); + entropy_count = 0; + } + nfrac = ibytes << (ENTROPY_SHIFT + 3); + if ((size_t) entropy_count > nfrac) + entropy_count -= nfrac; + else entropy_count = 0; if (cmpxchg(&r->entropy_count, orig, entropy_count) != orig) @@ -1376,6 +1386,7 @@ urandom_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) "with %d bits of entropy available\n", current->comm, nonblocking_pool.entropy_total); + nbytes = min_t(size_t, nbytes, INT_MAX >> (ENTROPY_SHIFT + 3)); ret = extract_entropy_user(&nonblocking_pool, buf, nbytes); trace_urandom_read(8 * nbytes, ENTROPY_BITS(&nonblocking_pool), |