locks: Handle negative values for flock->l_len

As per 'man 3 fcntl',
"If l_len is positive, the area affected shall start at
l_start and end at l_start+l_len−1. If l_len is negative,
the area affected shall start at l_start+l_len and end at
l_start−1. Locks may start and extend beyond the current
end of a file, but shall not extend before the beginning
of the file."

Currently we return EINVAL if l_len is found to be negative.
Fixed the same as mentioned in the man page.

This is backport of the below patch
    - http://review.gluster.org/11613

Change-Id: I493ce202c543185fc4ae7266d1aaf9d7e2a66991
BUG: 1312200
Signed-off-by: Soumya Koduri <skoduri@redhat.com>
Reviewed-on: http://review.gluster.org/11613
Reviewed-by: Kaleb KEITHLEY <kkeithle@redhat.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>
Reviewed-by: Raghavendra G <rgowdapp@redhat.com>
Reviewed-on: http://review.gluster.org/13526
Smoke: Gluster Build System <jenkins@build.gluster.com>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.com>

0 files changed, 0 insertions, 0 deletions