diff options
| author | Ralph Wuerthner <rwuerthn@de.ibm.com> | 2008-04-17 09:46:14 +0400 |
|---|---|---|
| committer | Heiko Carstens <heiko.carstens@de.ibm.com> | 2008-04-17 09:47:02 +0400 |
| commit | 893f11286644780fc7d6d415e537644da7bdaaf8 (patch) | |
| tree | 600401989687c7f7815ed119d2420b9228dd7e8d /drivers/char | |
| parent | c10fde0d9e2112c25052a8742e893ec5965c0007 (diff) | |
| download | linux-893f11286644780fc7d6d415e537644da7bdaaf8.tar.xz | |
[S390] hw_random: allow rng_dev_read() to return hardware errors.
The api for hardware random number generators is currently limited to
devices that never fail. If the hardware is registered as a source for
random numbers it has to work. This prevents the use of i/o based
random number devices where the i/o might fail.
Add a check for errors after the read from a hardware random number device.
This patch is required to support large random numbers retrieved
from the CEX2C cards on System z.
Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/hw_random/core.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index 84cdf9025737..349b6edc5794 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -116,6 +116,10 @@ static ssize_t rng_dev_read(struct file *filp, char __user *buf, err = -EAGAIN; if (!bytes_read && (filp->f_flags & O_NONBLOCK)) goto out; + if (bytes_read < 0) { + err = bytes_read; + goto out; + } err = -EFAULT; while (bytes_read && size) { |