From 4f29366f1e5678505fb882143c9b4a892d5b8273 Mon Sep 17 00:00:00 2001 From: Lyude Date: Tue, 30 May 2017 16:39:49 -0400 Subject: [PATCH] xwayland: Don't load extension list more than once MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When running an Xwayland server from the command line, we end up resetting the server every time all of the clients connected to the server leave. This would be fine, except that xwayland makes the mistake of unconditionally calling LoadExtensionList(). This causes us to setup the glxExtension twice in a row which means that when we lose our last client on the second server generation, we end up trying to call the glx destructors twice in a row resulting in a segfault: (EE) (EE) Backtrace: (EE) 0: Xwayland (OsSigHandler+0x3b) [0x4982f9] (EE) 1: /lib64/libpthread.so.0 (__restore_rt+0x0) [0x70845bf] (EE) 2: /usr/lib64/dri/swrast_dri.so (__driDriverGetExtensions_virtio_gpu+0x32897d) [0x1196e5bd] (EE) 3: /usr/lib64/dri/swrast_dri.so (__driDriverGetExtensions_virtio_gpu+0x328a45) [0x1196e745] (EE) 4: /usr/lib64/dri/swrast_dri.so (__driDriverGetExtensions_virtio_gpu+0x32665f) [0x11969f7f] (EE) 5: Xwayland (__glXDRIscreenDestroy+0x30) [0x54686e] (EE) 6: Xwayland (glxCloseScreen+0x3f) [0x5473db] (EE) 7: Xwayland (glxCloseScreen+0x53) [0x5473ef] (EE) 8: Xwayland (dix_main+0x7b6) [0x44c8c9] (EE) 9: Xwayland (main+0x28) [0x61c503] (EE) 10: /lib64/libc.so.6 (__libc_start_main+0xf1) [0x72b1401] (EE) 11: Xwayland (_start+0x2a) [0x4208fa] (EE) 12: ? (?+0x2a) [0x2a] (EE) (EE) Segmentation fault at address 0x18 (EE) Fatal server error: (EE) Caught signal 11 (Segmentation fault). Server aborting (EE) Easy reproduction recipe: - Start an Xwayland session with the default settings - Open a window - Close that window - Open another window - Close that window - Total annihilation occurs Signed-off-by: Lyude Reviewed-by: Michel Dänzer Signed-off-by: Peter Hutterer --- hw/xwayland/xwayland.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/hw/xwayland/xwayland.c b/hw/xwayland/xwayland.c index 7fc9bc0be..cc638ffd4 100644 --- a/hw/xwayland/xwayland.c +++ b/hw/xwayland/xwayland.c @@ -1013,8 +1013,9 @@ InitOutput(ScreenInfo * screen_info, int argc, char **argv) screen_info->bitmapBitOrder = BITMAP_BIT_ORDER; screen_info->numPixmapFormats = ARRAY_SIZE(depths); - LoadExtensionList(xwayland_extensions, - ARRAY_SIZE(xwayland_extensions), FALSE); + if (serverGeneration == 1) + LoadExtensionList(xwayland_extensions, + ARRAY_SIZE(xwayland_extensions), FALSE); /* Cast away warning from missing printf annotation for * wl_log_func_t. Wayland 1.5 will have the annotation, so we can