GETZCNT is supposed to return the number of threads that wait until
a semaphore value becomes 0.
The current implementation overlooks complex operations that contain
both wait-for-zero operation and operations that alter at least one semaphore.

The patch fixes that.
It's intentionally copy&paste, this will be cleaned up in the next patch.

Signed-off-by: Manfred Spraul <manf...@colorfullife.com>
---
 ipc/sem.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/ipc/sem.c b/ipc/sem.c
index 5749b9c..dc648f8 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -1047,6 +1047,16 @@ static int count_semzcnt(struct sem_array *sma, ushort 
semnum)
                            && !(sops[i].sem_flg & IPC_NOWAIT))
                                semzcnt++;
        }
+       list_for_each_entry(q, &sma->pending_alter, list) {
+               struct sembuf *sops = q->sops;
+               int nsops = q->nsops;
+               int i;
+               for (i = 0; i < nsops; i++)
+                       if (sops[i].sem_num == semnum
+                           && (sops[i].sem_op == 0)
+                           && !(sops[i].sem_flg & IPC_NOWAIT))
+                               semzcnt++;
+       }
        return semzcnt;
 }
 
-- 
1.9.0

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