BUG/MINOR: debug: fix "show fd" null-deref when built with DEBUG_FD

DEBUG_FD was added by commit 38e8a1c in 2.2-dev, and "show fd" was
slightly modified to still allow to print orphaned/closed FDs if their
count is non-null. But bypassing the existing test made it possible
to dereference fdt.owner which can be null. Let's adjust the condition
to avoid this.

No backport is needed.

diff --git a/src/cli.c b/src/cli.c
index b9afc1b20481e172ad44d6b0f248c7bc36b42596..3438fffe099aff7f5832b11dd4a03a08e298ad2c 100644 (file)
--- a/src/cli.c
+++ b/src/cli.c
@@ -1005,14 +1005,13 @@ static int cli_io_handler_show_fd(struct appctx *appctx)
                /* When DEBUG_FD is set, we also report closed FDs that have a
                 * non-null event count to detect stuck ones.
                 */
-               if (!fdt.owner
+               if (!fdt.owner) {
 #ifdef DEBUG_FD
-                   && !fdt.event_count
+                       if (!fdt.event_count)
 #endif
-                   )
-                       goto skip; // closed
-
-               if (fdt.iocb == conn_fd_handler) {
+                               goto skip; // closed
+               }
+               else if (fdt.iocb == conn_fd_handler) {
                        conn_flags = ((struct connection *)fdt.owner)->flags;
                        mux = ((struct connection *)fdt.owner)->mux;
                        ctx = ((struct connection *)fdt.owner)->ctx;