ipcs: fix ipc_sem_get_info fallback case

"ipcs -s -i n" (case id >= 0) was broken since v2.22-254-g1e2418a if /sys
is not usable.

See also comments for commit "ipcs: fix ipc_msg_get_info fallback case".

Signed-off-by: Ruediger Meier <ruediger.meier@ga-group.nl>

diff --git a/sys-utils/ipcutils.c b/sys-utils/ipcutils.c
index d92cdf5a78bd027f53f7ca072fe2b8fd728fd2c2..ef856f5b7909d74b418d7873e2514efa317723ab 100644 (file)
--- a/sys-utils/ipcutils.c
+++ b/sys-utils/ipcutils.c
@@ -295,29 +295,23 @@ int ipc_sem_get_info(int id, struct sem_data **semds)
 
        /* Fallback; /proc or /sys file(s) missing. */
 sem_fallback:
-       i = id < 0 ? 0 : id;
-
        arg.array = (ushort *) (void *)&dummy;
        maxid = semctl(0, 0, SEM_INFO, arg);
        if (maxid < 0)
                return 0;
 
-       while (i <= maxid) {
+       for (int j = 0; j <= maxid; j++) {
                int semid;
                struct semid_ds semseg;
                struct ipc_perm *ipcp = &semseg.sem_perm;
                arg.buf = (struct semid_ds *)&semseg;
 
-               semid = semctl(i, 0, SEM_STAT, arg);
-               if (semid < 0) {
-                       if (-1 < id) {
-                               free(*semds);
-                               return 0;
-                       }
-                       i++;
+               semid = semctl(j, 0, SEM_STAT, arg);
+               if (semid < 0 || (id > -1 && semid != id)) {
                        continue;
                }
 
+               i++;
                p->sem_perm.key = ipcp->KEY;
                p->sem_perm.id = semid;
                p->sem_perm.mode = ipcp->mode;
@@ -336,10 +330,12 @@ sem_fallback:
                        i++;
                } else {
                        get_sem_elements(p);
-                       return 1;
+                       break;
                }
        }
 
+       if (i == 0)
+               free(*semds);
        return i;
 }