From 3b3df3e52dd6adff483d8626c8f0801fd0ac05df Mon Sep 17 00:00:00 2001 From: Laszlo Ersek Date: Fri, 18 Jan 2019 23:31:52 +0100 Subject: [PATCH] fw_cfg: fix the life cycle and the name of "qemu_extra_params_fw" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 19bcc4bc3213 ("fw_cfg: Make qemu_extra_params_fw locally", 2019-01-04) changed the storage duration of the "qemu_extra_params_fw" array from static to automatic. This broke the interface contract on the fw_cfg_add_file() function, which is documented as follows, in "include/hw/nvram/fw_cfg.h": > [...] The data referenced by the starting pointer is only linked, NOT > copied, into the data structure of the fw_cfg device. [...] As a result, when guest firmware fetches the "etc/boot-menu-wait" fw_cfg file, it now sees garbage. Fix the regression by changing the storage duration to allocated. (The call is reached at most once, on the realize path of the board-specific fw_cfg sysbus device.) While at it, clean up the name and the assignment of the object as well. Cc: Gerd Hoffmann Cc: Markus Armbruster Cc: Philippe Mathieu-Daudé Fixes: 19bcc4bc3213e78c303ad480a7a578f62258252d Signed-off-by: Laszlo Ersek Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin Reviewed-by: Gerd Hoffmann Reviewed-by: Li Qiang Reviewed-by: Stefano Garzarella Reviewed-by: Philippe Mathieu-Daudé --- hw/nvram/fw_cfg.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c index 53e8e010a8..7fdf04adc9 100644 --- a/hw/nvram/fw_cfg.c +++ b/hw/nvram/fw_cfg.c @@ -118,7 +118,6 @@ static void fw_cfg_bootsplash(FWCfgState *s) { const char *boot_splash_filename = NULL; const char *boot_splash_time = NULL; - uint8_t qemu_extra_params_fw[2]; char *filename, *file_data; gsize file_size; int file_type; @@ -132,6 +131,8 @@ static void fw_cfg_bootsplash(FWCfgState *s) /* insert splash time if user configurated */ if (boot_splash_time) { int64_t bst_val = qemu_opt_get_number(opts, "splash-time", -1); + uint16_t bst_le16; + /* validate the input */ if (bst_val < 0 || bst_val > 0xffff) { error_report("splash-time is invalid," @@ -139,9 +140,9 @@ static void fw_cfg_bootsplash(FWCfgState *s) exit(1); } /* use little endian format */ - qemu_extra_params_fw[0] = (uint8_t)(bst_val & 0xff); - qemu_extra_params_fw[1] = (uint8_t)((bst_val >> 8) & 0xff); - fw_cfg_add_file(s, "etc/boot-menu-wait", qemu_extra_params_fw, 2); + bst_le16 = cpu_to_le16(bst_val); + fw_cfg_add_file(s, "etc/boot-menu-wait", + g_memdup(&bst_le16, sizeof bst_le16), sizeof bst_le16); } /* insert splash file if user configurated */