sysvipc: Return EINVAL for invalid msgctl commands

It avoids regressions on possible future commands that might require
additional libc support.  The downside is new commands added by newer
kernels will need further glibc support.

Checked on x86_64-linux-gnu and i686-linux-gnu (Linux v4.15 and v5.4).

diff --git a/sysdeps/unix/sysv/linux/msgctl.c b/sysdeps/unix/sysv/linux/msgctl.c
index a1f24ab242813dd03fe5e012ab61d904e27afcef..f4493de573c7ab8cbb4bfb75fd782aac1963613c 100644 (file)
--- a/sysdeps/unix/sysv/linux/msgctl.c
+++ b/sysdeps/unix/sysv/linux/msgctl.c
@@ -88,25 +88,46 @@ __msgctl64 (int msqid, int cmd, struct __msqid64_ds *buf)
 {
 #if __IPC_TIME64
   struct kernel_msqid64_ds ksemid, *arg = NULL;
-  if (buf != NULL)
+#else
+  msgctl_arg_t *arg;
+#endif
+
+  switch (cmd)
     {
-      /* This is a Linux extension where kernel returns a 'struct msginfo'
-        instead.  */
-      if (cmd == IPC_INFO || cmd == MSG_INFO)
-       arg = (struct kernel_msqid64_ds *) buf;
-      else
+    case IPC_RMID:
+      arg = NULL;
+      break;
+
+    case IPC_SET:
+    case IPC_STAT:
+    case MSG_STAT:
+    case MSG_STAT_ANY:
+#if __IPC_TIME64
+      if (buf != NULL)
        {
          msqid64_to_kmsqid64 (buf, &ksemid);
          arg = &ksemid;
        }
-    }
 # ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
-  if (cmd == IPC_SET)
-    arg->msg_perm.mode *= 0x10000U;
+      if (cmd == IPC_SET)
+       arg->msg_perm.mode *= 0x10000U;
 # endif
 #else
-  msgctl_arg_t *arg = buf;
+      arg = buf;
 #endif
+      break;
+
+    case IPC_INFO:
+    case MSG_INFO:
+      /* This is a Linux extension where kernel returns a 'struct msginfo'
+        instead.  */
+      arg = (__typeof__ (arg)) buf;
+      break;
+
+    default:
+      __set_errno (EINVAL);
+      return -1;
+    }
 
   int ret = msgctl_syscall (msqid, cmd, arg);
   if (ret < 0)

diff --git a/sysvipc/test-sysvipc.h b/sysvipc/test-sysvipc.h
index d7ed496511c10afb9583514e1478d226412cfdb2..21ef6c656581519e0ab8de07220a33a54dc5ec8b 100644 (file)
--- a/sysvipc/test-sysvipc.h
+++ b/sysvipc/test-sysvipc.h
@@ -82,4 +82,29 @@ first_sem_invalid_cmd (void)
   return invalid;
 }
 
+/* Return the first invalid command SysV IPC command for message queue.  */
+static inline int
+first_msg_invalid_cmd (void)
+{
+  const int msg_cmds[] = {
+    MSG_STAT,
+    MSG_INFO,
+#ifdef MSG_STAT_ANY
+    MSG_STAT_ANY,
+#endif
+  };
+
+  int invalid = first_common_invalid_cmd ();
+  for (int i = 0; i < array_length (msg_cmds); i++)
+    {
+      if (invalid == msg_cmds[i])
+       {
+         invalid++;
+         i = 0;
+       }
+    }
+
+  return invalid;
+}
+
 #endif /* _TEST_SYSV_H  */

diff --git a/sysvipc/test-sysvmsg.c b/sysvipc/test-sysvmsg.c
index 84efdade5edf29490ae7d8ecc6d06a93c0ad9753..ada28810656158de4a6d99ae4481f8fa93a75fa8 100644 (file)
--- a/sysvipc/test-sysvmsg.c
+++ b/sysvipc/test-sysvmsg.c
@@ -24,6 +24,8 @@
 #include <sys/ipc.h>
 #include <sys/msg.h>
 
+#include <test-sysvipc.h>
+
 #include <support/support.h>
 #include <support/check.h>
 #include <support/temp_file.h>
@@ -86,6 +88,9 @@ do_test (void)
       FAIL_EXIT1 ("msgget failed (errno=%d)", errno);
     }
 
+  TEST_COMPARE (msgctl (msqid, first_msg_invalid_cmd (), NULL), -1);
+  TEST_COMPARE (errno, EINVAL);
+
   /* Get message queue kernel information and do some sanity checks.  */
   struct msqid_ds msginfo;
   if (msgctl (msqid, IPC_STAT, &msginfo) == -1)