From eb9fa4c2d786b327bb4d9bd7727428c70a33c710 Mon Sep 17 00:00:00 2001 From: Baptiste Daroussin Date: Fri, 3 Jan 2025 10:50:30 +0100 Subject: libusb: fix hotplug sigbus When a hotplug callback has been registered, and the program using libusb is calling libusb_exit then the thread handler is set to NO_THREAD which result in the variable controlling the loop the be set to 0, it does a last pass through device available without having done a scan, which result in a sigbus after it tried to unregister all the devices. directly break the loop instead and cleanup the list of devices this fixes the tests with LGPLed libusb's hotplugtest program MFC After: 3 days Reviewed by: kevans Differential Revision: https://reviews.freebsd.org/D48298 (cherry picked from commit ba5834b8e11fd002a663d083a464e397e76cb3a9) --- lib/libusb/libusb10_hotplug.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/lib/libusb/libusb10_hotplug.c b/lib/libusb/libusb10_hotplug.c index 9d00b1dbe5a0..98903686f76b 100644 --- a/lib/libusb/libusb10_hotplug.c +++ b/lib/libusb/libusb10_hotplug.c @@ -112,22 +112,25 @@ libusb_hotplug_scan(void *arg) libusb_device *temp; libusb_device *adev; libusb_device *bdev; - unsigned do_loop = 1; - while (do_loop) { + for (;;) { usleep(4000000); HOTPLUG_LOCK(ctx); + if (ctx->hotplug_handler == NO_THREAD) { + while ((adev = TAILQ_FIRST(&ctx->hotplug_devs)) != NULL) { + TAILQ_REMOVE(&ctx->hotplug_devs, adev, hotplug_entry); + libusb_unref_device(adev); + } + HOTPLUG_UNLOCK(ctx); + break; + } TAILQ_INIT(&hotplug_devs); - if (ctx->hotplug_handler != NO_THREAD) { - if (libusb_hotplug_enumerate(ctx, &hotplug_devs) < 0) { - HOTPLUG_UNLOCK(ctx); - continue; - } - } else { - do_loop = 0; + if (libusb_hotplug_enumerate(ctx, &hotplug_devs) < 0) { + HOTPLUG_UNLOCK(ctx); + continue; } /* figure out which devices are gone */ -- cgit v1.3