qcow2: Discard unaligned tail when wiping image

[mirror_qemu.git] / qemu-io-cmds.c

diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
index 2c48f9ce1a6d81f8f992f8c942e52253dafae45e..883f53b64d3cf79998fae66f822568c915e0278b 100644 (file)
--- a/qemu-io-cmds.c
+++ b/qemu-io-cmds.c
@@ -35,6 +35,13 @@ static int compare_cmdname(const void *a, const void *b)
 
 void qemuio_add_command(const cmdinfo_t *ci)
 {
+    /* ci->perm assumes a file is open, but the GLOBAL and NOFILE_OK
+     * flags allow it not to be, so that combination is invalid.
+     * Catch it now rather than letting it manifest as a crash if a
+     * particular set of command line options are used.
+     */
+    assert(ci->perm == 0 ||
+           (ci->flags & (CMD_FLAG_GLOBAL | CMD_NOFILE_OK)) == 0);
     cmdtab = g_renew(cmdinfo_t, cmdtab, ++ncmds);
     cmdtab[ncmds - 1] = *ci;
     qsort(cmdtab, ncmds, sizeof(*cmdtab), compare_cmdname);