Fix Connectathon locking test failure

 We currently fail Connectathon test 6.10 in the case of 32-bit locks due
 to incorrect error checking.
 Also add support for l->l_len < 0 to 64-bit locks.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/locks.c b/fs/locks.c
index 7eb1d77b9204deccce359d4b2f9f1e9ffcb954ab..a1e8b2248014c0aa1d7ae8b2766440f753929908 100644 (file)
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -316,21 +316,22 @@ static int flock_to_posix_lock(struct file *filp, struct file_lock *fl,
        /* POSIX-1996 leaves the case l->l_len < 0 undefined;
           POSIX-2001 defines it. */
        start += l->l_start;
-       end = start + l->l_len - 1;
-       if (l->l_len < 0) {
+       if (start < 0)
+               return -EINVAL;
+       fl->fl_end = OFFSET_MAX;
+       if (l->l_len > 0) {
+               end = start + l->l_len - 1;
+               fl->fl_end = end;
+       } else if (l->l_len < 0) {
                end = start - 1;
+               fl->fl_end = end;
                start += l->l_len;
+               if (start < 0)
+                       return -EINVAL;
        }
-
-       if (start < 0)
-               return -EINVAL;
-       if (l->l_len > 0 && end < 0)
-               return -EOVERFLOW;
-
        fl->fl_start = start;   /* we record the absolute position */
-       fl->fl_end = end;
-       if (l->l_len == 0)
-               fl->fl_end = OFFSET_MAX;
+       if (fl->fl_end < fl->fl_start)
+               return -EOVERFLOW;
        
        fl->fl_owner = current->files;
        fl->fl_pid = current->tgid;
@@ -362,14 +363,21 @@ static int flock64_to_posix_lock(struct file *filp, struct file_lock *fl,
                return -EINVAL;
        }
 
-       if (((start += l->l_start) < 0) || (l->l_len < 0))
+       start += l->l_start;
+       if (start < 0)
                return -EINVAL;
-       fl->fl_end = start + l->l_len - 1;
-       if (l->l_len > 0 && fl->fl_end < 0)
-               return -EOVERFLOW;
+       fl->fl_end = OFFSET_MAX;
+       if (l->l_len > 0) {
+               fl->fl_end = start + l->l_len - 1;
+       } else if (l->l_len < 0) {
+               fl->fl_end = start - 1;
+               start += l->l_len;
+               if (start < 0)
+                       return -EINVAL;
+       }
        fl->fl_start = start;   /* we record the absolute position */
-       if (l->l_len == 0)
-               fl->fl_end = OFFSET_MAX;
+       if (fl->fl_end < fl->fl_start)
+               return -EOVERFLOW;
        
        fl->fl_owner = current->files;
        fl->fl_pid = current->tgid;