From 47106ac435e891ced67f0ad9bb6b2ee12098c880 Mon Sep 17 00:00:00 2001 From: NIIBE Yutaka Date: Wed, 28 Nov 2018 14:59:44 +0900 Subject: [PATCH] scd: Serialize opening device by select_application. * scd/app.c (app_new_register): Don't lock APP_LIST_LOCK here. (select_application): Lock with APP_LIST_LOCK earlier. -- What we want to do here is to serialize the call of select_application. In the old code, it was possible that a call of select_application was blocked internally, and then another call of select_application entered. We can have a dedicated lock for call of select_application, but it is easier to re-use APP_LIST_LOCK. Signed-off-by: NIIBE Yutaka --- scd/app.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/scd/app.c b/scd/app.c index a82db26cd..d16300efa 100644 --- a/scd/app.c +++ b/scd/app.c @@ -299,11 +299,8 @@ app_new_register (int slot, ctrl_t ctrl, const char *name, } app->periodical_check_needed = periodical_check_needed; - - npth_mutex_lock (&app_list_lock); app->next = app_top; app_top = app; - npth_mutex_unlock (&app_list_lock); unlock_app (app); return 0; } @@ -322,6 +319,8 @@ select_application (ctrl_t ctrl, const char *name, app_t *r_app, *r_app = NULL; + npth_mutex_lock (&app_list_lock); + if (scan || !app_top) { struct dev_list *l; @@ -330,7 +329,10 @@ select_application (ctrl_t ctrl, const char *name, app_t *r_app, /* Scan the devices to find new device(s). */ err = apdu_dev_list_start (opt.reader_port, &l); if (err) - return err; + { + npth_mutex_unlock (&app_list_lock); + return err; + } while (1) { @@ -365,7 +367,6 @@ select_application (ctrl_t ctrl, const char *name, app_t *r_app, scd_kick_the_loop (); } - npth_mutex_lock (&app_list_lock); for (a = app_top; a; a = a->next) { lock_app (a, ctrl);