Bug 1312200

+++ This bug was initially created as a clone of Bug #1241104 +++

Description of problem:

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. A lock shall be set to extend to the largest possible value of the file offset for that file by setting l_len to 0. If such a lock also has l_start set to 0 and

But in the current lock handling,

int
pl_lk (call_frame_t *frame, xlator_t *this,
       fd_t *fd, int32_t cmd, struct gf_flock *flock, dict_t *xdata)
{
......
.........

        if ((flock->l_start < 0) || (flock->l_len < 0)) {
                op_ret = -1;
                op_errno = EINVAL;
                goto unwind;
        }
.......
.......
}

We invariably return error if l_len is found to be negative. It needs to be fixed.

--- Additional comment from Anand Avati on 2015-07-10 03:22:26 EDT ---

REVIEW: http://review.gluster.org/11613 (locks: Handle negative values for flock->l_len) posted (#1) for review on master by soumya k (skoduri)

--- Additional comment from Anand Avati on 2015-07-10 07:22:41 EDT ---

REVIEW: http://review.gluster.org/11613 (locks: Handle negative values for flock->l_len) posted (#2) for review on master by soumya k (skoduri)

--- Additional comment from Vijay Bellur on 2016-02-23 04:53:04 EST ---

REVIEW: http://review.gluster.org/11613 (locks: Handle negative values for flock->l_len) posted (#3) for review on master by soumya k (skoduri)

--- Additional comment from Vijay Bellur on 2016-02-25 04:35:29 EST ---

COMMIT: http://review.gluster.org/11613 committed in master by Raghavendra G (rgowdapp) 
------
commit e410c3a0c97a7bfe109badba5b6a5dd094016995
Author: Soumya Koduri <skoduri>
Date:   Fri Jul 10 12:40:24 2015 +0530

    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.
    
    Change-Id: I493ce202c543185fc4ae7266d1aaf9d7e2a66991
    BUG: 1241104
    Signed-off-by: Soumya Koduri <skoduri>
    Reviewed-on: http://review.gluster.org/11613
    NetBSD-regression: NetBSD Build System <jenkins.org>
    Smoke: Gluster Build System <jenkins.com>
    Reviewed-by: Kaleb KEITHLEY <kkeithle>
    CentOS-regression: Gluster Build System <jenkins.com>
    Reviewed-by: Niels de Vos <ndevos>
    Reviewed-by: Raghavendra G <rgowdapp>