From 7b22e05582037c5f88b38039a99e48ddf2150cbd Mon Sep 17 00:00:00 2001 From: Zhao Liu Date: Mon, 11 Mar 2024 11:37:56 +0800 Subject: [PATCH] block: Fix missing ERRP_GUARD() for error_prepend() As the comment in qapi/error, passing @errp to error_prepend() requires ERRP_GUARD(): * = Why, when and how to use ERRP_GUARD() = * * Without ERRP_GUARD(), use of the @errp parameter is restricted: ... * - It should not be passed to error_prepend(), error_vprepend() or * error_append_hint(), because that doesn't work with &error_fatal. * ERRP_GUARD() lifts these restrictions. * * To use ERRP_GUARD(), add it right at the beginning of the function. * @errp can then be used without worrying about the argument being * NULL or &error_fatal. ERRP_GUARD() could avoid the case when @errp is &error_fatal, the user can't see this additional information, because exit() happens in error_setg earlier than information is added [1]. In block.c, there are 4 functions passing @errp to error_prepend() without ERRP_GUARD(): - bdrv_co_create_opts_simple() - parse_json_filename() - bdrv_open_backing_file() - bdrv_append_temp_snapshot() bdrv_co_create_opts_simple(), is an implementation of BlockDriver.bdrv_co_create_opts(). There are too many possible callers to check the impact of this defect; it may or may not be harmless. Thus it is necessary to protect @errp with ERRP_GUARD(). Though the @errp parameters passed to parse_json_filename(), bdrv_open_backing_file() and bdrv_append_temp_snapshot() points to their callers' local_err, to follow the requirement of @errp, also add missing ERRP_GUARD() at their beginning. [1]: Issue description in the commit message of commit ae7c80a7bd73 ("error: New macro ERRP_GUARD()"). Cc: Kevin Wolf Cc: Hanna Reitz Cc: qemu-block@nongnu.org Signed-off-by: Zhao Liu Reviewed-by: Eric Blake Message-ID: <20240311033822.3142585-4-zhao1.liu@linux.intel.com> Signed-off-by: Thomas Huth --- block.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/block.c b/block.c index 1ed9214f66..cf66c767a0 100644 --- a/block.c +++ b/block.c @@ -633,6 +633,7 @@ int coroutine_fn bdrv_co_create_opts_simple(BlockDriver *drv, QemuOpts *opts, Error **errp) { + ERRP_GUARD(); BlockBackend *blk; QDict *options; int64_t size = 0; @@ -1998,6 +1999,7 @@ fail_opts: static QDict *parse_json_filename(const char *filename, Error **errp) { + ERRP_GUARD(); QObject *options_obj; QDict *options; int ret; @@ -3585,6 +3587,7 @@ int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, const char *bdref_key, Error **errp) { + ERRP_GUARD(); char *backing_filename = NULL; char *bdref_key_dot; const char *reference = NULL; @@ -3851,6 +3854,7 @@ static BlockDriverState *bdrv_append_temp_snapshot(BlockDriverState *bs, QDict *snapshot_options, Error **errp) { + ERRP_GUARD(); g_autofree char *tmp_filename = NULL; int64_t total_size; QemuOpts *opts = NULL; -- 2.11.4.GIT