diff --git a/backend/x11/output.c b/backend/x11/output.c
index 181c2de14..51a9c1441 100644
--- a/backend/x11/output.c
+++ b/backend/x11/output.c
@@ -19,6 +19,7 @@
 #include <wlr/util/log.h>
 
 #include "backend/x11.h"
+#include "render/pixel_format.h"
 #include "util/time.h"
 #include "types/wlr_buffer.h"
 #include "types/wlr_output.h"
@@ -167,11 +168,20 @@ static bool output_test(struct wlr_output *wlr_output,
 
 	if (state->committed & WLR_OUTPUT_STATE_BUFFER) {
 		struct wlr_buffer *buffer = state->buffer;
-
-		if (buffer_get_drm_format(buffer) != x11->x11_format->drm) {
+		uint32_t format = buffer_get_drm_format(buffer);
+		if (format != x11->x11_format->drm) {
 			wlr_log(WLR_DEBUG, "Unsupported buffer format");
 			return false;
 		}
+		struct wlr_shm_attributes shm;
+		if (wlr_buffer_get_shm(buffer, &shm)) {
+			const struct wlr_pixel_format_info *info = drm_get_pixel_format_info(format);
+			if (shm.stride != pixel_format_info_min_stride(info, shm.width)) {
+				// xcb_shm_create_pixmap() does not allow arbitrary strides.
+				wlr_log(WLR_DEBUG, "Unsupported shm buffer stride");
+				return false;
+			}
+		}
 	}
 
 	if (state->committed & WLR_OUTPUT_STATE_MODE) {
@@ -261,6 +271,12 @@ static xcb_pixmap_t import_shm(struct wlr_x11_output *output,
 		return XCB_PIXMAP_NONE;
 	}
 
+	const struct wlr_pixel_format_info *info = drm_get_pixel_format_info(shm->format);
+	if (shm->stride != pixel_format_info_min_stride(info, shm->width)) {
+		// xcb_shm_create_pixmap() does not allow arbitrary strides.
+		return XCB_PIXMAP_NONE;
+	}
+
 	// xcb closes the FD after sending it
 	int fd = fcntl(shm->fd, F_DUPFD_CLOEXEC, 0);
 	if (fd < 0) {