From 52f993b8e89487ec9ee15a7fb4979e0f09a45b27 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Wed, 8 Mar 2017 23:13:28 -0800 Subject: Upgrade to 4.4.50-rt62 The current kernel is based on rt kernel v4.4.6-rt14. We will upgrade it to 4.4.50-rt62. The command to achieve it is: a) Clone a git repo from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git b) Get the diff between this two changesets: git diff 640eca2901f3435e616157b11379d3223a44b391 705619beeea1b0b48219a683fd1a901a86fdaf5e where the two commits are: [yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only 640eca2901f3435e616157b11379d3223a44b391 640eca2901f3 v4.4.6-rt14 localversion-rt [yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only 705619beeea1b0b48219a683fd1a901a86fdaf5e 705619beeea1 Linux 4.4.50-rt62 localversion-rt c) One patch has been backported thus revert the patch before applying. filterdiff -p1 -x scripts/package/Makefile ~/tmp/v4.4.6-rt14-4.4.50-rt62.diff |patch -p1 --dry-run Upstream status: backport Change-Id: I244d57a32f6066e5a5b9915f9fbf99e7bbca6e01 Signed-off-by: Yunhong Jiang --- kernel/drivers/char/random.c | 42 +++++++++++++++++++++++++++--------------- 1 file changed, 27 insertions(+), 15 deletions(-) (limited to 'kernel/drivers/char/random.c') diff --git a/kernel/drivers/char/random.c b/kernel/drivers/char/random.c index 29abd5fa5..cf69b6b42 100644 --- a/kernel/drivers/char/random.c +++ b/kernel/drivers/char/random.c @@ -722,15 +722,18 @@ retry: } } -static void credit_entropy_bits_safe(struct entropy_store *r, int nbits) +static int credit_entropy_bits_safe(struct entropy_store *r, int nbits) { const int nbits_max = (int)(~0U >> (ENTROPY_SHIFT + 1)); + if (nbits < 0) + return -EINVAL; + /* Cap the value to avoid overflows */ nbits = min(nbits, nbits_max); - nbits = max(nbits, -nbits_max); credit_entropy_bits(r, nbits); + return 0; } /********************************************************************* @@ -941,6 +944,7 @@ void add_interrupt_randomness(int irq, int irq_flags, __u64 ip) /* award one bit for the contents of the fast pool */ credit_entropy_bits(r, credit + 1); } +EXPORT_SYMBOL_GPL(add_interrupt_randomness); #ifdef CONFIG_BLOCK void add_disk_randomness(struct gendisk *disk) @@ -1453,12 +1457,16 @@ 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); @@ -1538,8 +1546,7 @@ static long random_ioctl(struct file *f, unsigned int cmd, unsigned long arg) return -EPERM; if (get_user(ent_count, p)) return -EFAULT; - credit_entropy_bits_safe(&input_pool, ent_count); - return 0; + return credit_entropy_bits_safe(&input_pool, ent_count); case RNDADDENTROPY: if (!capable(CAP_SYS_ADMIN)) return -EPERM; @@ -1553,8 +1560,7 @@ static long random_ioctl(struct file *f, unsigned int cmd, unsigned long arg) size); if (retval < 0) return retval; - credit_entropy_bits_safe(&input_pool, ent_count); - return 0; + return credit_entropy_bits_safe(&input_pool, ent_count); case RNDZAPENTCNT: case RNDCLEARPOOL: /* @@ -1842,12 +1848,18 @@ void add_hwgenerator_randomness(const char *buffer, size_t count, { struct entropy_store *poolp = &input_pool; - /* Suspend writing if we're above the trickle threshold. - * We'll be woken up again once below random_write_wakeup_thresh, - * or when the calling thread is about to terminate. - */ - wait_event_interruptible(random_write_wait, kthread_should_stop() || + if (unlikely(nonblocking_pool.initialized == 0)) + poolp = &nonblocking_pool; + else { + /* Suspend writing if we're above the trickle + * threshold. We'll be woken up again once below + * random_write_wakeup_thresh, or when the calling + * thread is about to terminate. + */ + wait_event_interruptible(random_write_wait, + kthread_should_stop() || ENTROPY_BITS(&input_pool) <= random_write_wakeup_bits); + } mix_pool_bytes(poolp, buffer, count); credit_entropy_bits(poolp, entropy); } -- cgit 1.2.3-korg